Thursday, 30 April 2015

4 metres: Germany on, Italy off, rigs notably absent.

Since the late 1950s, many UK hams (and some other European ones too) have been fixated on the 4 metre/ 70MHz band. I guess that includes me.

This is not the place to account for the history of this rather odd allocation. Later maybe. But many VHF enthusiasts find that it is the perfect meeting ground for a variety of conditions not shared by surrounding bands.

It gets:-
more tropo than 50MHz;
more Sporadic E than 144MHz,
antennas with an ideal size/gain combination and;
it is (arguably) the best band for meteor scatter.

Also, it is a hidden gem. There are very few commercial rigs. You have to be a "special" amateur enthusiast to work it.

The only real way to get onto 4m is to assemble some bits and plug them together. This "high technical requirement" thins out the numbers with the capability to get on the band. (Now that IS sarcasm). Some real enthusiasts built their own gear. Many have built the "OZ" transverter. Some bought the FT-847, some versions of which theoretically can work on 4m. However, those people soon found that the FT-847 needed as much effort to get going as would have built several OZ transverters.

But more of that later.

Latest news is that Germany has issued another limited time permit for full licencees to operate on 4m. This time it covers 70.150 to 70.180, 25W ERP. There was similar thing last year, but it had a much less friendly allocation of frequencies down in the beacon portion. So this is good news. Also, this one runs from now until the end of August 2015, so it covers most of the 4m Es season.

4m coverage tends to expand in this way. Certain German licencees already have single frequency allocations on 69.950 and 69.990. That was good start. Then we had the bottom slice of band opened up for a fixed period last year. Then an even better slice of band opened up this year. Maybe one day we will have even better terms. It will all work if we behave ourselves and do not cause any interference to other non-amateur operators.

The current Spanish allocation was something similar. First Spanish operators appeared on the band and then left again. Fixed term licences. Then they were back, then they left again. Then they stayed but on a conditional basis. Now, this year, they have a slice of the band on a permanent basis.

These slices of band rarely overlap. We have to resort to split frequency operation (Macedonia has two fixed frequencies 70.075 and 70.275, Lithuania has 70.240 to 70.250 - work that one out). Do we care? No. It just makes for more challenges. Any slice of band is helpful. It is not easy but who said it should be?

The downside of all this is the situation in Italy. As of this minute, Italian amateurs do not have 70MHz. They have had repeated short spells of operation over the past few years. That must be frustrating for the many keen Italian VHF amateurs. It is ironic that many other amateurs use Italian made (Sirio) antennas.

One of my favourite contacts on any band was working IK3FKX on 4m FM. To say that he was amazed would be an understatement, as he was having a cross town natter on a PMR (old taxi radio). We proceeded in a mix of half-English, half my schoolboy Latin, and he sent me a pile of material in the post which I still have on my pin board.

The present situation is a real step forward over the days when I was first licenced. Then, the only countries which had the band were UK, Republic of Ireland and Gibraltar. But we knew that it had potential. I give full credit to the many who worked hard behind the scenes to get the European band we now have.

"The problem", if there is one, behind getting more countries onto the band, is that these frequencies are often used for "state" purposes. So we need to tread carefully. Often, there have to be agreements with defence users, or there are certain frequencies allocated to PMR users. There are border issues between states. Over time, though, these can often be solved. In Russia and a few related states it is used for broadcasting, so that is a harder nut to crack.

As for "the rig problem" - I have heard enough of it. It does not exist.

I was reading a thread on another site about how terrible it is that the Yaesu FT-991 does not have 70MHz. Eh? Of course it doesn't. The FT-991 has an IF in the region of 70MHz. It would be hideously difficult to get it to work on 70MHz. If people cannot work out a simple technical issue like that, they will never get far on 70MHz. We have the IC-7100, a good way on to the band at a reasonable price. We have Spectrum transverters, which are good value for money. We have ME4T transverters for the more committed, and the Kuhne ones for the people who should be committed (seriously good kit, those). Then we have good commercial kit on FM for anyone who wants to get round Europe from time to time. Why do we need more rigs?

My simple guide to a way on to 4m for the non-technical.
1) Buy rig.
2) Buy transverter
3) Buy antenna patch leads
4) Plug together
5) Switch on 
I do not believe that this is a barrier to entry, but I may be wrong of course.

Let me give you an example. 6m is a very good band. When it first appeared in Europe, almost no rigs in the UK covered 6m and the band was fragmented in different states. People said there should be more rigs. Over time, almost every HF rig now comes with 6m. Most European countries now have a common band. Are there many people on the 6m band? No.

This is not about the rigs. 6m is a brilliant band, but I know dozens of amateurs who have 6m rigs who do not ever set foot on 6m. The same goes for 2m. The idea that more easily available 4m rigs would change the band is ludicrous. The band will still be the band it is, no matter how much those lazy non-operators complain.

VHF dx is a dedication rather than an easy way of doing amateur radio. Even on 2m, the bands in Europe have a fraction of the activity they had in the days I was first licenced. VHF (6m, 4m and 2m) is a specialist sport, a place apart. It is a space in which you have to be ready to listen to hours of white noise. To transmit for a hour, and hear no reply (I just did that very thing). It has to be difficult because it is difficult. But when it works, it is glorious.

If 20 metres SSB is the football of radio, or 2m FM on a repeater is the gentle stroll, 2m SSB is a marathon, 6m is the Tour de France and 4m is an Iron Man Triathlon. To suggest that it should be made easier is like suggesting that Vincenzo Nibali would do better on  a motor bike, or that Mo Farah would go faster in a 4x4.

I am away to try to work Germany.

Do you think I am still angry?

73

Jim

Wednesday, 29 April 2015

Fault finding the FVM (angry) way

Grrr. I was SO angry yesterday. I was tearing my hair out and blaming everybody for what was going wrong with my Flex 1500.

I called CQ on meteor scatter on 70.230. I was called by EI4KF. We could not finish the QSO after an hour. He could hear me, but I could not hear him.

This is what Erik was seeing (rig 1 is the Flex/ME4T) ...
I only have a blank screen to show.

I tried both the Flex/ME4T combination, and the IC-7100 but it was mostly Flex/ME4T.

I got one burst from Erik which gave me his callsign and report. Apart from that I heard nothing, yet he could hear me both by tropo and by meteor scatter. I sense that this had happened before with other stations using data modes.

This is very frustrating as he had spent a lot of his time and I was getting nowhere.

It almost seemed as if I could hear weak signals in the speakers which were not decoding in the WSJT software.

It is true that he was running his full legal power (50 watts) and I was running 125 watts. Also, I have a 3dB higher noise level in his direction. But still, that was a poor result at my end.

I can cut a lot of this description out. I can save you the 24 hours of jiggling I did to pin the blame down to the virtual audio cable (VAC) level coming out of the Flex. I eliminated the WSJT software, the VACs themselves (by loading different VACs which were worse), and in fact everything else. It HAD to be the VAC output from the Flex. That was as far as I got when I stormed out yesterday evening.

The problem boiled down to this. I could turn the pre-amp on and off and that produced a 12dB change in the noise on the Flex waterfall and on the speakers. But the VAC was unchanged, as shown by the noise level on the WSJT software. Something was acting to keep the VACs 100% full of noise.

Eventually I noticed that the Flex "AGC-T" slider does not work as I had expected on VAC. Certainly, it reduces the noise on the display and the speakers. However, at the default setting of 90 it was stopping the WSJT software reacting to changes in level from the receiver. In effect it was overdriving the VAC at that level, though nothing was apparent on the screen or on the speaker. Reducing the AGC-T to 73 restored normality. that setting produced the same 12dB reduction in the VAC output as shown on the screen and heard in the speakers.

So basically the output to the VACs was being overdriven on receive, unknown to me.

I have no idea why the output to the VACs would be overdriven when the display and speakers showed no problem. The VACs themselves were fine, and reducing their gain controls just meant that the overdriven signal reduced in volume at the other end. So whatever it is occurs inside the PowerSDR software not the VACs.

I have now read a lot more about the AGC-T settings. I certainly looks as if Flex think that they should be adjusted on a band by band if not QSO by QSO basis. No chance of that here with data and so forth in operation. However, I can see that my combinations of filters, pre-amp and band settings on the Flex may have got things out of kilter.

So I have re-set AGC-T to 73. Let us see what happens next. Certainly, the beacons sound good on it. The spin off on the screen and speakers seems to be beneficial too.

I am still suffering with the cold. Maybe that is why I got so cross with all this. I had to shut down and leave the room. I was REALLY ANGRY. Not angry with the rig, angry with myself for not knowing what was wrong, and wasting Erik's time. Plus I need his square! I took it out on my new rig which was ordered in December and still has not arrived. I fired off some emails and generally got my frustration over that out too.

Sometimes I think it is not necessarily bad to blow your top. I have put up with a lot over the non-appearance of this mystery rig. So it was time to express that. The issue with the Flex just got me wound up ready to fire.

Anyway, normality has been restored for a while.

I need to work some DX on meteor scatter to prove everything is OK. And maybe take an "anger management" course.

Jim
GM4FVM
P.S. Just worked OK2BRD at 1528km. Seems to be working?

Tuesday, 28 April 2015

My HF antenna, the Sirio Gainmaster.

This is not going to be easy to illustrate as I cannot get an effective photo of it. It is 7.36m tall from the base to the tip, so I need a pretty wide angle lens to get it all in.

I tried and this is the result. Most of the photo is the Tennamast; the Srio is on the left.
The wind seems to be catching it as it is not quite vertical. I see that Sirio recommend using guys in certain situations:-

- Locations subjected to strong wind or constant gusts of wind (eg: coast and mountain areas).
- Locations with cold winter conditions and frequent formation of ice layers on the antenna body. In fact, the different distribution of the weight, can change substantially the resistance to the wind.
We therefore recommend at least 3 ties "NYLON" bracing to be fixed at the junction between 2° and 3° fiber pipe (see drawing).


Anyway, I like balanced antennas and I do not like "ground plane" antennas. The ground here is VERY dry and sandy. There is no ground plane to be had here, and I would need to add lots of radials. I had been toying with the idea of a vertical dipole but they are hard to construct. You need to support them in the middle and run the co-ax away at right angles, which means very heavily built supports.

While I was thinking about how to do this, I discovered that Sirio make this vertical dipole, basically as a CB antenna. The details are on the Sirio website here. I bought it on eBay from a supplier in England I have used a lot and it cost about £100. Not cheap.

It seems to be a "sleeve dipole" or a "co-axial dipole". With this design you basically take a length of co-ax and strip the braid off the last 1/4 wavelength. This becomes half your antenna, and the 1/4 wavelength of braid before the stripped bit becomes the other half. Straight away this is not very satisfactory, and you need some method of isolating the braid part of the antenna from the rest of the co-ax, as otherwise unbalanced currents flow down your co-ax and give you all sorts of SWR problems.

I do not know how Sirio have dealt with this (everything is encapsulated) but there is a large coil of red co-ax at the bottom of the antenna.

I guess that this coil is in fact a "choke balun" designed to stop currents on the co-ax braid. That would isolate the rest of the co-ax from the currents in the antenna portion of the braid. A choke balun is not really a balun in the conventional sense (it is not a "transformer"), but it does tend to act as a choke to stop currents on the braid.

So far, so good. The two main features of the Gainmaster are understood by me. I did look long and hard at the publicity before I bought one. Vertical sleeve dipole - OK I get that: choke balun - yes,  use those, fine. But Sirio had another trick up their sleeve (dipole). The antenna is not 1/2 wave in total length but 5/8 wave. It has long been known that 5/8 is a better radiator than 1/4 or 3/4 wave. The disadvantage of this is that it needs a matching circuit to make it usable on 50 ohm co-ax (all those coils on the bottom of mobile whips do that). So that Gainmaster has a matching circuit (I think a capacitor and a coil - I forget) matching the impedance at the point where the braid is cut. Clever.

I do not know now why a 5/8 has good radiation efficiency. Maybe I did know once and I have forgotten. Anyway we do not need a string of complex formulae, let us just accept it as a fact. If you know, there is no need to write in and tell us - unless you really want to.

So this is not just a vertical 1/2 wave dipole but a 5/8 wave vertical dipole (or 0.625 wavelength as Sirio call it). No fractions in Roman numerals? The elements are copper inside a fibreglass outer whip. You get the whip in four sections and the elements wrapped up. There is a bit of assembly to do. The ends of the fibreglass sections are split and held by "Jubilee clips" aka "worm drive hose clips". I wrapped the joints in the fibreglass with self amagamating tape which has lasted three years and now needs to be replaced.

I did some tests comparing the Sirio with a driven element of my G4MH mini-beam. So that was roughly 1/2 wave horizontal dipole compared to 5/8 wave vertical dipole. I used two separate rigs and compared transmission and reception reports for the same stations over the same paths at the same time. WSPR is great for these tests. The Sirio never did worse than the horizontal dipole, and nearly always did better. This was despite me turning the horizontal dipole right at the stations. So I took the horizontal dipole off the mast and it has been the Sirio ever since.

The Sirio has some drawbacks. It is one band only - though I do use it on 12 metres sometimes. The antenna it replaced covered 10m, 15m and 20m. On the other hand it works brilliantly well. There is nothing to do but put it up. It needs no radials, no counterpoises, no tuning and you do not need to rotate it. VK on half a watt - no problems. And - perfect for WSPR - it is omni-directional.

Personally, I think it is great if you like the 10 metre band. It is a real DX antenna.

73

Jim
GM4FVM

Monday, 27 April 2015

10m WSPR going well, 6m WSPR frustrating.

Here is my map for the last 24 hours on 10m WSPR

2-ways on 0.5 watts to places like Australia (including Tasmania), Falkland Islands and many US states. Not bad.

Falkland Islands is one I always have a fond spot for, having worked VP8NO and VP8PC back on 9 October 1977, so it counts as a bit of dx history for me. At that point I had only worked about 5 stations outside Europe, so a rare one was nice.

On the other hand, 6m WSPR is pretty bleak.
The maps shows the rough area I might expect to reach if there is some Sporadic Es. The German stations are mostly just listening. The UK stations and PA0O are too close. That only leaves LA5TFA. As sporadic E is very selective, the chances of reaching him are low.

I say the UK stations are too close, but I did get this, which I think is a slight tropo lift at 295km ..

2015-04-26 15:24  GM4FVM  50.294471  -26  -2  IO85wu  +37  5.012  G4TJJ  IO93gf  295  183 

It would really take a large number of stations in France, Spain, Italy, Poland, Finland, etc, to produce some sort of coverage which Es might have a chance to hit. That seems unlikely to happen.

Of course, human nature being what it is, as soon as Es does become established, we get a lot more stations on the band. But by that time it is too late to learn about early season Es.

WSPR is not very popular, on any band, in Eastern Europe.

Still, we have what we have. We just have to work with it.

Chances are, if there is an Es opening, I will move off to JT65 and SSB, and thus abandon WSPR. I bet that WSPR could fill in a lot of gaps in our knowledge if it had a good year-round coverage of 6m. Not much chance of that.

I think that people just want to turn on their rigs and see some callsigns. They are not interested in how the propagation might develop - and thus they miss things.

There are some bright spots though. CN8LI often comes on 6m during the season and his results are always interesting. And we sometimes get stations on the Canary Islands too.

We should be thankful for what we have.

73

Jim - still waiting for a VHF Es contact this season.

Sunday, 26 April 2015

Is it worth getting up early in the morning?

Normally, I would say that it is NOT worth getting up early in the morning. For radio, maybe, but for my general mood, NO.

This time I have had a cold. I have been coughing and spluttering. Mrs FVM has just finished two weeks working in London making the money to buy the rigs. She was totally exhausted and my coughing was waking her up. So I got up at 05:00. No point me keeping her awake.

I turned on the radios and set everything up, sat down to watch Frasier on the TV and fell asleep.

On WSPR  I managed this:-

2015-04-26 07:00  GM4FVM  28.126087  -24  0  IO85wu  +27  0.501  VK2KRR  QF34mr  16748  10407 
 2015-04-26 06:56  LZ1OI  28.126043  -25  -1  KN22jc  +40  10.000  GM4FVM  IO85wu  2463  1530 
 2015-04-26 06:56  VK3AMW  28.126024  -29  0  QF22ir  +37  5.012  GM4FVM  IO85wu  16797  10437 
 2015-04-26 06:10  VK2KRR  28.126041  -18  0  QF34mr  +40  10.000  GM4FVM  IO85wu  16748  10407 


A two way to VK2KRR - well, only 50 minutes between me hearing him and him hearing me. I was hearing other VKs and JH1GYE. He was running 10 watts and I was running 0.5W. Generally most WSPR fans stick to 5W as the max. I am not going to increase to 5W just to be heard by a lot of stations. I want to see how well 500mW works and the World just needs to adjust to fit round me.

The only station to hear me between 05:00 and 08:45, so far, has been that one spot from VK2KRR. Yep, I am sure that some of the 50 or so stations I can hear could also hear me if I ran more power, but that would rather defeat my objects here. I was running low power, nobody in Europe could hear me, but I was heard 16,000km away. I like that.

Anyway, Frasier was over and the new 6m antenna has been tested. I heard SP2HRR pretty loud on the meteor scatter frequency of 50.230, calling for replies on 50.244. We then had a very quick QSO. It is still the end of the Lyrids meteor shower (missed most of that) so his signals were pretty easy to hear (and see!).

This is the sort of trace I like to see on meteor scatter. Nice strong pulses. Easily heard on the speaker. The QSO was over in less than 10 minutes.
JT6M, which is the mode most used on 6m, does have a lot of garbage coming up in the screen during QSOs. On FSK441, which is used on higher frequencies, you get much less garbage. However, FSK is not really suited to long periods of reception, it is more for very short bursts. Shorter than these ones anyway.

JT6M has been superseded by ISCAT, but most 6m operators stick to JT6M. Pity really. It must be frustrating for the developers to devise a new and better mode and find that amateurs do not take it up. I believe that PSK was devised to replace RTTY, which, sadly, it has not done. I do not like RTTY at all.

I think that a 1326km meteor scatter QSO, using an antenna with a boom length less than a metre, slung up just over the level of the roof, with a standard 100W transceiver, is pretty good. I keep hearing the cry "6m is dead" from people who cannot plug A into B and work some stuff. OK, the stations at the other end may have 6m booms and fancy kit, but you can do OK without it.

Speaking of which, cold or no cold, there was a break in the cloud and rain yesterday and I put up the Sirio 4m vertical again. Much lower than before but at least it is up for now. The locals were complaining that it is too low. Well, for now it will have to do.

My 4m FM rig is my propagation detector. It scans channels from 69.990 to 70.500, and it is great at spotting Sporadic E lifts. For that purpose the antenna does not need to be very high. Sporadic E, like meteor scatter and aurora, has signals arriving from quite a high angle. So the antennas do not need to be very high. I am not very bothered about not being able to hear locals on 6m or 4m, so they will have to accept this. The dx will get through.

Having said all that, both the 6m HB9CV and the 4m vertical will be going as high as I can get them in due course. Highest is best for dx, whatever the angle of propagation.

However, I have to proceed in gradual steps - ideally not spending any money as I go.

73

Jim.

Friday, 24 April 2015

Denmark on 2metres, 6metres Es heard and more antenna work

Last things first. The 6m antenna is now up. But the 4m vertical has come down.

These were the brackets which held up the Sirio 4m vertical. The plan was that the 6m beam would go underneath that, but it quickly emerged that this was a non-starter. The Sirio is too heavy and long. That Conrad rotator is not very strong and it would have been crazy to try. I stood on the scaffold tower and felt the weight of the whole thing and decided that it would not do. So I put up my X30 (Diamond-alike) 2 metre vertical instead. So that is done for now. I still have to tack up the rotator control cable and the coax, but that can be done later.

There is a good 75cm of mast below the brackets and this combination could go higher up if I feel I can rely on the rotator in the winds. For now, let us give it a try. Once again I made a mistake about the bottom pole. I thought that the rotator would take a 50mm diameter pole, but it doesn't. Thus it is back on the 35mm ones. The real solution is a better rotator and 50mm poles.

I now need to sort out some other 4m vertical. The Sirio is heavy but it could go on the weak bracket which the 6m beam was temporarily on (and before that the 2m vertical). The snag is, how do I put something heavy on that? OR, it could go on the main mast, but that would put a 4m vertical right above a 4m horizontal beam. Some thought required there. I asked the very helpful and wise Brian, G0MJI, who thinks that the vertical over beam thing would work but he raised the good point that I might overload the FM rig while transmitting on the SSB one. Hmmm. Don't want to blow up my fancy preamp by blasting it with 25 watts FM from an antenna 6 inches away from the beam.

Has anybody noticed that all I do is swop everything round like musical chairs?

Not as much as another ham I could name.

Nice to hear Josep, EA6SA on the beam in its new position. Proper 6 metre Es that was, but he did not hear me. IC-7100 weak audio and a blown linear, I only have myself to blame.

I did get an immediate email from a certain GM DXer, pointing out the unfairness of me finding Es after he had done a whole day's antenna work and missed it. Well, unfairness was not the word he used. I had to point out that I only HEARD Es, but it cut no ice. Some people think I lead a charmed DX life, and they may be right. Anyway, I had done a whole day's antenna work so I deserved it.

I was in Birmingham earlier in the week. I went in the train. Some of my former workmates were having a jolly so I went along. We did travel on this beast of a thing. I used to work in the rail industry, and I have to say that the level of service has improved no end since my day ...
There was nothing like that in my day. Still, the reason for this digression was that I got home on Wednesday, turned on the IC-7100 on 2 metres SSB and there was Dan OZ1BEF, followed by Thomas OV3T. I have worked Thomas before, but it was nice to get some tropo in. I thought I had missed it by going off in the train to Brum for the first half of the week. I heard Thomas for some time, but the band faded and they were gone. Nothing else heard on tropo that night, nor since.

73

Jim


Friday, 17 April 2015

Is the IC-7100 a bit deaf on 4 metres?

Someone on another site posed this question.

Is the IC-7100 a bit deaf on 4 metres?

In my view, yes. A bit.

Someone else said, it is "deafer than a deaf thing". That is going a bit far for me, but that is what he finds. I do always run a preamp in front of it, so he has a point.

Several people have done the best test possible - they have compared the IC-7100 with other rigs on their bench. That is a vastly better test than just replacing one rig with another and trying to remember what the first one was like. And that produces the impression (as they report) that the IC-7100 is better than a PMR FM rig (and so it should be). Then again, it is on a par with an older design of FM mobile and not quite as good as the latest multi-band mobile rigs. Interesting, but presumably that is on FM, which is hard to compare. You would expect it to be better than a £150 FM mobile and not worse than a £250 multi-band FM mobile, as it does cost over £1000.

Another person has compared the 7100 with a TS480 and a Spectrum transverter (a sensitive transverter that, or so I found with three of them at various times), and a Noble (now there is a good rig, how did he get one?) and he found the IC-7100 is worse than those.

Someone else uses a pre-amp which he says "transforms" the 7100.

Well, here I use the GaAsFET preamp and the pre-amps in the 7100 itself. And I compared that against the Flex 1500/ME4T-Pro transverter and the FT-817 and the same transverter. The transverter was better than the IC-7100 on both rigs, even the transverter with the FT-817. Just to remind you, the FT-817 is basically a 20 year old design of portable without DSP and costs half the price - though it does not cover 4 metres. Whereas the 7100 claims to be state of the art.

Worth thinking about this if 4 metres is all you are looking for --- don't write off transverters just yet. The FT-817 and the ME4TPro transverter, new, are cheaper than the 7100. Hardly comparable and I would not necessarily recommend it, but still if you are looking for a 4m rig ... and the ME4TPro and the Flex 1500 are about the same. You might expect the IC-7100 to outclass those combinations on 4 metres, but in many ways it does not. And the ME4TPro here is giving a full 33 watts on 4m SSB, the 7100 only 20 out of its claimed 50! The Spectrum is cheaper, did not perform as well as the ME4TPro for me, but by recent accounts can show a clean set of heels to the Icom. The Spectrum has other issues (frequency stability, power output and strong signal handling) but is not to be sniffed at by comparison with a far more expensive "all-singing all dancing" rig which has issues.

Of course a single band rig, such as the Noble, or a single band transverter, such as the ME4T or the Spectrum, can be tweaked for maximum performance on that one band. On the other hand, the IC-7100 is a multi-band rig with 4m as an add-on.

But what do I mean by "better"? Frankly, I think it is noise performance rather than sensitivity as such. I find that the transverter is best when I am straining with the cans on to find a weak beacon or something. That stands out from the noise better on the others than on the IC-7100. As an example, I might say that my first ME4T receiver section equal to the Spectrum, but the newer ME4T-Pro has a better low noise mixer and that shows in really weak signal performance.

Simply put, I can hear things on the ME4TPro that I can not hear on the IC-7100. In that way the transverter is "better".

The transverter does most of the work. The rig driving it can be quite simple, like the FT-817, though the added features of the Flex do make life much easier.

Unless you are straining for the last ounce of performance I doubt if the IC-7100 will let you down. But I am. And lets us not forget that I am using a high performance pre-amp as well. What it comes down to (for me) is not that the 7100 is insensitive, it is that it fails to perform well at really low signal levels where signal to noise is key.

Someone said, if I hear a weak signal on the 7100 and turn on the preamp it gets better. Right. I am saying I can hear things on other equipment that I cannot hear on the 7100, preamp or not. At some level a preamp will increase the noise, and if the wanted signal is not capable of being resolved by the rig, you are expecting a lot from a preamp to solve the problem. If the noise performance of the rig is not good enough then all you are doing is raising the level of the noise and the signal which is being swamped by noise inside the rig anyway.

My father always refused a hearing aid. He said that he could hear sounds, it was the clarity which he was lacking. I find that the IC-7100 is lacking the clarity he was talking about.

As I said in an earlier post, the IC-7100 has strengths and weaknesses. I am not changing anything I wrote then. However, I have moved the 7100 to 50MHz and 144MHz use here. I also feel that an FT991 might do that job better too. Whereupon my 7100 could become my multi-band FM rig, and the one I take on caravan trips. What a waste that would be.

It is OK. It could be a lot better.

73

Jim
GM4FVM

Thursday, 16 April 2015

Alpacas, work and propagation, almost.

It has been a busy couple of days. I have actually had to work. I am not so busy, generally, being a self employed part timer, that work gets in the way of important things like radio. But sometimes work has to be done. Self employment brings many benefits, but you feel you have to work when there is work to do.

I did manage to get out on my walk. 10,000 steps a day is the target and today so far it is 11,799 (yesterday 11671). Who said I was a "target man"? And I managed to see the alpacas. There are four but one was standing a bit far away. They are a long way from the Peruvian Andes, but it was cold enough last night for frost here. There are looking quite wooly now.

Anyway, the Sporadic E season has started here on 10 metres. It was good to see Gianfranco IU1DZZ on my WSPR waterfall. Mind you, I managed to lose the USB connection to the rig. So I posted Gianfranco's contact as on 12 metres, but it was indeed on 10m. I do not know definitely why this is happening, but I am pretty sure it is because the USB connector is on an outboard USB3 hub. I shall try to connect it more directly to the PC.

There was a general Es opening at fairly good strength from here into Northern Italy on 10m. It lasted from about 13:30 to around 17:00. There was also an opening on 6m along the same path but I heard nothing at all of that. So no 6m Es yet, nor anything on higher frequencies either.

The thing about working from home is that you can build your workplace at the back of the shack. So there I was, five rigs running, an Es opening on WSPR being copied, and muggins here working away whilst listening to the cricket on the computer. Multi-tasking I think it is called.

Later, around 19hrs I heard a very strong meteor scatter QSO on 70MHz. Try as I might I could not resolve either station. It sounded like ISCAT, looked like FSK, but neither mode would decode. I also tried JTMS but I was getting nowhere. Then, as I watched the Flex monitor, I noticed a CW station about 20kHz lower. Bounding down it was GM3WUX in Glasgow on aurora. Three cheers for the Flex panoramic display, where you can see stations you cannot hear.

I can only guess that the stations I could not decode were in the Nordic Activity Contest somewhere in Scandinavia, and the signals were so distorted by the aurora I could not copy them.

Of course I had no idea there was an aurora until I saw GM3WOJ. I could not raise WOJ. His signal faded and turned back into a non-distorted weak tropo tone. I heard GM4VVX quite strongly on aurora but I could not raise him either. I heard a Swedish 2m beacon too but that was it. I had a good chat with Andy GM8OEG and that was the day done.

The original plan, that is yesterday's plan, was for today to be doing antenna work. Then came the extra work, and sadly I could not get out apart from the walk. Still, watching the Es and hearing the aurora was good. However, the antenna work is still not done. The work task is not finished either, so it looks like tomorrow is accounted for too.

73
Jim
GM4FVM

Monday, 13 April 2015

Climbing, conditions and General Shufflebottoms returns

Argh! I never saw anything like it.






Doug, GM6ZFI arrived to help with the brackets, and promptly ignored the platform on the scaffold tower. He charged straight up the rungs at the side and balanced himself up there. I say balanced, he put his foot on one of the very weak crossbars - you can see it bend. He looks happy enough, and I can see why I did not do it that way.

The point is, Doug is a professional electrician and he is used to this type of thing. And he knows what is safe and what is not safe. He proceeded with great care, using protective clothing, goggles and ear protection, and it was real eye opener. He knows what he is doing, however scary it looks to me (I took that photo from a height: from underneath holding the scaffolding it felt that he was very high). It does look scary to me, which is proof that I was better to bring in someone who has spent years working up high.

What he has done is to lower the top bracket below what was the bottom one. It is now at a height that I can work on it safely from the platform on the scaffolding. Hopefully over the next few weeks I can get the 6m antenna sorted out once and for all (well, until I change it next time). Those brackets should be able to support something a lot better than the current HB9CV. Which would need a better rotator ...

I really appreciate what Doug did for me today. Doug is a real gent and a true radio amateur. He drove over here and did all this, provided the fixings, all for no payment. All I could get him to accept was coffee and a sausage roll in the Rialto Cafe in Eyemouth. I owe him several favours for that work today.

Yesterday and today brought Sporadic E to 6 metres in Europe.  A couple of stations in Scotland got in on some of it, but nothing was heard from here.

10 metre conditions are still struggling. It took 43 hours of silence, during and after the geomagnetic storms, for me to receive just one spot - and then not another one for hours after that. Although there have been a couple of longer distance spots on WSPR, generally I have been getting weak spots from Belgium. Nice but not earth shattering.

Shufflebottoms is back. Having just recast everything in the shack, I have already swapped the HF and 4m rigs. Although the FT-817 was doing passably well driving the 4m transverter, I relented and put the Flex on that duty instead. The FT-817 is now on 10 and 12 metre bands.

There is some logic to that. It was the set-up here about a year ago. It allows me to run the transverter on 1mW rather than 5W. OK, the transverter has an attenuator to reduce the power if needed, but also the Flex can also use separate tx and rx leads. This means that, should I forget to turn the transverter on, or the PTT lead falls out, or some other failure occurs, then I am txing 1mW into a dead end. If I was using 5W from the single cable FT-817, I would be txing 5W into the receiver section of the transverter - which is expensive as it blows everything up. It has never happened to me, but I do not like tempting fate.

The FT-817 receiver is OK; the Flex has a better receiver. And for some reason the Flex is driving the transverter harder than it was. Whatever Gabi, HA1YA, did to the transverter when he gave it a make-over has done the trick. I have also provided the linear with a dedicated power supply right beside it to reduce voltage loss in the supply leads. All this means that I can get the full legal 150 watts output on 4m. Not that I am running more than 100W in normal service, of course.

So that is where we are today. If I decide that the Flex/transverter set-up is not very good on meteor scatter, which was my mad belief before (impossible, surely), everything will change ... again.

73

Jim
GM4FVM

Saturday, 11 April 2015

WSPR Update number 2 - yippee, "dead" band!!!


(Edit - this picture of no activity seems to have disappeared.!!!)


Who'd have thought it?

10m WSPR, at lunchtime on a Saturday in mid-April, zero activity worldwide.

Two medium geomagnetic storms in the early hours of 10 and 11 April 2015 have reduced the ionosphere to a quivering wreck. Long spells of negative Bz - in other words the magnetic field of the particles arriving from the Sun are in the right direction for maximum effect on the Earth's magnetic field) can trigger an aurora and so forth. But on this occasion, the particles are not energetic enough, nor travelling fast enough, to trigger an aurora. So we have have had two days of particles raining into the Earth's ionosphere and ruining the radio conditions for DX. "Radio Blackout" as it was called in the days when long distance radio was the communications medium of the world.

Give it a day or two and it will recover and normal service will be resumed. The Solar Flux Index is currently 115, a pretty poor number for this stage in the 11-year solar cycle. This is a very poor cycle for solar flux levels, and their related sun spot numbers. Sure, we can still have solar activity which can affect our radio conditions (e.g. today's blackout and the 17 March aurora), but so few sunspots deliver while they are pointed right at us, simply because there are so few sunspots in this cycle.

Since I last addressed this issue, my WSPR performance has not been too bad. Not on 50MHz which has not got me out of the British Isles, and Sporadic E has not yet arrived at 50MHz around here, yet. But on 28MHz it has not been too bad.

Being heard in VK on 100mW is quite good for me


2015-04-07 11:40  GM4FVM  28.126088  -26  -1  IO85wu  +20  0.100  VK6YS  OF77xt  14638  9096 

... which works out at 146380 km/watt

Being heard in the US on 10mW is also interesting

15-03-25 17:54  GM4FVM  28.126082  -18  0  IO85wu  +10  0.010  WG2Z  FN21oa  5335  3315 

... just 533500 km/W. And with a signal like -18dB, I could hopefully have gone down to 1mW and still have got a copy (5,000,000 km/W).

But it did not happen at 1mW. Dropping the power in both cases lost the stations so I need to try again. I have done over 2,000,000 km/W on 10m Sporadic E. Doing that kind of thing on normal F layer DX propagation to another continent is hard. Getting a two-way WSPR confirmation is even harder given that so many WSPR-ers are content to just run 5 watts and use their time to investigate inefficient antennas instead.

Whatever emerges, WSPR contacts do not count as QSOs for me. For a QSO to count in my book you have to convey the Callsigns and Signal Reports and confirm receipt. WSPR does not convey signal reports so it is a beacon mode. A very interesting beacon mode, but that is it.

WSPR is also a "inverse beacon" mode. You can transmit and then get reports back via the internet as to how you are received by distant stations. That makes it very useful for antenna and propagation monitoring.

Perhaps even more useful for me is that is shows which paths I can use for QSOs. If someone can hear me on 1 watt on WSPR, I can usually work that area on, say, 20 watts of JT65. That is how many of my contacts into VK have resulted. I didn't know there was a path most days on 10m into VK at about 11:00 in Spring and Autumn, WSPR showed me that.

As I have never worked ZL, this interested me:-
2015-04-09 11:08  ZL3DMH  28.126079  -26  -2  RE66im  +37  5.012  GM4FVM  IO85wu  18591  11552 
I heard him, but he did not hear me. At the time I was only running 20mW. He was very weak at -26dB, but could a JT65 contact work?

This is "a possibility". I love possibilities. A target to reach, or maybe just strive towards.

If I just wanted to work people I could go on 20m, buy a kilowatt linear, or use an internet linking VOIP system. What is the point of that for me? What would I learn? It is fine for those who need to fill their log book, or work someone every day. But the spectrum I use (10m and VHF) does not provide goodies every day. Sometimes we got nothing on the map, as above. It makes the good days more interesting. And, KEY POINT, a "dead" band makes us try harder. Try new modes, try smart operations, do more, think, think, think. Learn.

I believe this hobby is here for us so that we can learn about radio. If I do not learn, what is the point (for me). OK, if you just want to chat, you do that. I am not stopping you. But for me, if I do not learn about wiring things up, using them, or learn about the wonderful world of propagation and Earth Science, then I would rather not bother at all.

A "dead" band is an interesting band. Because, unlike humans, they won't stay dead for ever.

In fact, 10m and VHF never produces dead bands. Just sleeping ones. They all wake up eventually.

73

Jim
GM4FVM

Friday, 10 April 2015

Rig swap

It is time to meet "General Shufflebottoms". Time to move everything around for the summer.

This has been prompted by the demise of my 6m 100W linear (temporary I hope). Also snagging is that I have ordered a rig to replace one here and it has not arrived after 4 months!  But enough of that.

Meet the new General (who is back because he was sacked from somewhere else)

General back in charge is the M+E ME4T-Pro 70 MHz transverter.


Everything else has shuffled about:-

2m -
No change - Icom IC-7100 and Microset SR200 linear


4m -
WAS Icom IC7100 + TE 0610G,
NOW FT817 + ME4T-Pro Transverter + TE 0610G linear.

6m -
WAS Flex 1500 + RM VLA150 (RIP),
NOW Icom IC-7100

10m -
WAS FT817 + RM KL203 linear
NOW Flex 1500 + KL203 linear.

So what does that prove?

I can now run 100 watts again on 6m, without the RM VLA-150 linear that went arrrggghhh. I am now using again a beautiful piece of equipment, the M+E ME4T-Pro transverter. This really nice piece of kit has been off to Hungary for a make-over by Gabi (HA1YA), the man who built it in the first place. Gabi says it is working better than ever and I think he is right. Suddenly I can hear the Buxton beacon which I never heard on the Icom IC-7100.

But sadly driving the ME4T is the FT-817. This is not the best bit of gear ever (as discussed earlier in this blog). How-and-ever, it seems to be better than the Flex 1500 for this task just now. Let us just try and see. I have plugged in an outboard speaker and I use a desk mike.

It is not easy to get the FT-817 to accept data and CAT controls while at the same time sending PTT to the transverter. However, I have made up a lead to allow this and so far so good. The power output of the 817 falls as it gets hot on data. In the past I have added a fan. Right now the transverter has the fan, controlled off the PTT line via the linear. Maybe I can set the 817 on top of the transverter to share the air flow. Anyway, I have set it up so that the "PWR" control on the ME4T can cover the range by which the 817 loses umph.

If all of this work looks like a big kerfuffle to do very little, that is in deed true. The idea was that  I would have a dedicated 4m rig here by now. But that has not happened. The drawback of bringing back the transverter, just as it has always been, is that using 28MHz as the IF for the transverter gets in the way of 28MHz WSPR. Which was why I wanted to stop using the transverter in the first place. But just for now I will have to accept that.

This will last until I sack the General again and bring in the new General, who is the old failed General from somewhere else.

Never throw anything out or sell it. As soon as it is gone you will be wanting to shuffle it back into use.

73

Jim
GM4FVM

Tuesday, 7 April 2015

Flex 1500 and data modes (PSK, WSPR, JT65 etc).

This is going to be long and detailed, so brace yourself. This is a pain but you only do it once (ahem!) and the Flex is brilliant once set up. Other SDR rigs will be similar.

With a traditional non-SDR rig like an FT-817 you would use two types of real lead, a PTT (or CAT) lead, usually from a USB socket on your computer, and an audio lead plugged into an audio card. You would have to buy these leads. With the Flex and other SDR rigs you can do all the connecting together inside the computer. Instead of connecting a computer to a rig with real leads, you are connecting one piece of software (your data program) to a different piece of software (the Flex operating system) and passing the data inside the computer.

Just to warn you at the start, I use "Control Panel" on my PC set to display "Small Icons". By default it is set to "Category". You had better change yours to small icons or a lot of the navigation within Windows will not make sense. You can do it by Category, but it is very fiddly. It is fiddly enough already.

The Flex 1500 is a well known route for many people into Software Defined Radio (SDR). It is a 5 watt output transceiver, small, with just one control on the box, an on/off switch. Everything else is controlled via the computer it needs to drive it.

The idea is simple enough. It covers general coverage receive from 490kHz to 54MHz and transmits in all amateur bands in that range. If you buy the rig it comes with a version of "Power SDR" software to drive it. As supplied the transmit frequencies are limited to amateur bands in your area, and you need to get the rig "turfed" if you want to transmit in other areas or if a new band is authorised in your area.

I have had mine for over 4 years now (now is April 2015). I bought it initially to use it as a transverter driver. It is well suited to this as it has 1mW (0dBm) output sockets at the back, plus the ability to use separate receiver sockets and configurations which mean that your frequency in the PowerSDR screen is correct for your transverter. I used it this way with three or four different transverters before I started using rigs designed for the bands involved. Since then my Flex is used mostly for 6 metres, or sometimes 10 and 12 metres - almost always on data modes.

The Flex has done me well and I have used it frequently. In fact, it is now one of the longer-lived pieces of equipment in the shack. You would have to say that it has a brilliant receiver in that it has the SDR ability to use a wide range of filters, plus the computer controlled ability to move around the band using the fantastic SDR software.
This image shows the Flex receiving on 70.201 (using a transverter). You can see a CW signal on 70.200, the calling frequency. Very handy. You can see signals not on the frequency you want to use. The display shows about 40kHz of band and you can show a panoramic display, a waterfall, both, or several other interesting graphical outputs. I have used this feature to jump from PSK to JT65 as I notice different signals (only works when the frequencies are within the range of the display). Very handy for beacons too. This proved invaluable to me dozens of times.

The Flex 1500 has two receivers, and I have used both to receive WSPR and JT65 at the same time on 10 metres, though you can only transmit on one. Fine, but they both need to be within the display range.

That screenshot of PowerSDR above also shows a problem, a second "image". The second signal below (to the left of) 70.200 is in fact an "image" and is not really a second station. All superhet rigs have images, it is just that you usually cannot see them. Often they fall outside your range of use. They are usually going at some multiple of the tuning rate in the wrong direction. I have never actually replied to an image (they are usually reversed sideband so do not work in data, but they could fool you in CW). They stick out a mile. However, they are an issue with the Flex.

OK, so on to data modes (at last you say!).

With the modes I use, I set up the PowerSDR to work the push to talk ("PTT") and inject an audio tone into the rig. It is just like using cables to connect a computer to a standard rig, but all the cables are virtual and inside the computer. There are four cables I use in total, two serial cables for the PTT with a numbered port at each end, and two audio cables with sound inputs and outputs at each end.

You can set PowerSDR up in memory so that if you click a memory setting like "6m WSPR" the rig will go to the right frequency, select the right mode (DIGU), correct filter, and switch from microphone input to "VAC" (more about VAC later). Then if you click something you have saved at "6m SSB" all that can be reversed at one click of the button - magic. But the memory does not recall the audio settings, which you have to change separately. for example, I need much more rx drive for FSK441 than I do for WSPR. Still, the audio has memories too, so I set those up for "WSPR" or "SSB" and that makes just two clicks to make.

That audio settings problem would be solved, incidentally, if all WSJT programmes had variable audio input and output like WSJT-X. But on WSJT10 you can vary the input level but not the output, and on WSPR2.11 you can vary the output but not the input. I know that there are plans to bring the all together, but that will take time.

So, to connect the Flex 1500 to a data program like WSPR or Ham Radio Deluxe (HRD) you need to cover the two aspects. One is the PTT and CAT line (2 virtual serial cables) and the other is the audio line (2 different virtual audio cables).

For PTT you can connect to PowerSDR either by CAT or simple PTT. PowerSDR accepts either and I always set up both. Some data programs, like WSJT10, do not have CAT.  Others like HRD are best used via CAT. So it is easier to set up both though you only need one at a time.


As both WSJT10 (our current example), and the PowerSDR software, are on the same computer, you will use "virtual serial ports" (VSP) connected by a virtual cable for CAT and PTT. Thus when WSJT "presses the PTT", the PTT signal goes by digital connection to PowerSDR and tell it to pess the TX button.

The VSP I use is "VSP Manager" by Steve Nance (K5FR). You can get it from him at k5fr.com. At the time of updating this link (09 Jan 2016), it works if you click HERE. I will do my best to keep the links up to date but if this does not work you may need to contact K5FR directly.

Quite reasonably K5FR asks you to let him know you are using it. He says this:-
================================
If you are an Amateur Radio Operator and would like to use VSP Manager for your *Personal* use, contact me with your call letters and I'll be happy to send you a copy.
Please Note! If you're not a licensed Amateur Radio Operator don't bother to apply. There are no exceptions to this rule.
================================
It is free and he is letting us use it, so fair enough. An SWL does not need it of course. They can skip directly to the audio connections, lucky people.

You simply download, install, and set up VSP Manager. It asks you to select a pair of ports which are connected by a virtual cable. I install two pairs, one for CAT and one for PTT. This allows non-CAT programs like WSJT10 to point to one, and CAT programs like HRD to point to the other.

So I set up pairs of Virtual Serial Ports at each end of the cable. I call one pair 6 and 16, and the other 8 and 18. Don't ask why, that was suggested by an article on the Flex site. Keeping one number of the pair below 10 is a good plan as some programs are fussy about that, and the other is just 10 above for convenience.

What you need to imagine is that there is a lead with port 6 and one end and port 16 at the other end, and sending a PTT signal to port 6 will cause the signal to come out at port 16. Thus you can connect together two ports and save a real cable.

Make sure that 6 and 8 (and their pairs16 and 18) are not already used on your computer. It isn't very likely but you can check in vspManager as shown above. If they were in use, they would be listed under "Physical Ports". When you plug in something controlled via a USB socket, Windows will give it a number for the next highest port it thinks is free. If you find that 6 and 8 are already allocated by Windows, go to "Start", "Control Panel", "Device Manager", pick the "Ports" tab, find your ports and any that use 6 or 8, select them, go to into "Port Settings" then "Advanced" and simply change the number away from 6 or 8 (or 16 and 18).

Even after you have chosen to use 6 and 8, Windows can sometimes allocate the number to something else you plug in for the first time, so it is something to keep an eye on.

VSPManager has a habit of telling you that it has failed to create the ports, but just continue to set them up and they will work, at least you might have to reboot the PC first (it has to be a PC, the PowerSDR/ Flex combination doesn't like anything else but apparently it will run in Wine).

OK, you are ready to go setting up PTT with the VSP. We will deal with CAT later. Connect the PTT program (e.g. WSJT10 in this case) to com port 6. That is one end of the imaginary cable. In WSJT10 it is called "PTT port" and you have to enter the number directly.
Obviously, given what I have said before, the other end of the cable must be port 16, and you need to connect it into PowerSDR. You find that in the "Setup" tab under "CAT Control"

Connect COM 16 into the PTT control by using the drop down menu and selecting port 16.Then click "enable PTT" before you select enable CAT. YOU HAVE TO DO PTT FIRST, SELECT IT, AND THEN DO CAT SECOND - if you need CAT too. Even though this photo shows both connected, you cannot set CAT first and PTT second.
Right, I now suggest you reboot and check that the rig goes into transmit when the program suggests it should. You have not connected the audio yet so it should not transmit any signal, just show transmit in PowerSDR.

OK, for CAT type programs, I suggest you follow the above first as you never know when PTT might be useful. Then you select port 8 in your program (in this case WSJT-X as in the photo below). Note that the PTT is set as well as the CAT, and WSJT-X will work in this mode but if you change band the rig will not change automatically with you unless you have CAT selected, nor will the +2khz button work without CAT).
Note that for CAT operation you need to select a common baud rate - in WSJT you will see that I have set the "serial rate" to 9600, and in the setup CAT tab in PowerSDR above the rate is also set to 9600. 9600 is low, but it works for me! If you have problems with CAT, suspect the baud rate (you might need to set a common baud rate in the setting in "COM Ports" in the Control Panel of you PC). However, 9600 is so low it rarely causes problems.

Note too that the Flex emulates a Kenwood TS-2000 by default. You can chose other settings, but those work fine for me.

If you are using something like WSJT-X you can test the PTT and the CAT using buttons on the setup screen.

OK, that is the PTT and CAT sorted out. What about the audio?

Just like PTT, you can keep the audio connections inside the PC. You CAN use real live audio cables just like you would with an FT-817 or whatever, in that case two audio cards in your PC and an audio cable between them. I have done it! It works! However, it is very lossy, getting the levels right is a pain and I would not recommend it. Keeping it inside the PC using virtual cables is much better.

What you need here is a virtual audio cable (VAC). You can buy one from Russia. It works and my credit card was not ripped-off. However, I found the Russian ones hard to set up and given to breaks in service. So I recommend VB Cables which you can find HERE. These are freeware - I donated a few Euros and they sent me a very nice email thanking me for the money.

No big deal with the VB cables. Once again you have to imagine a cable. A virtual audio device (which will appear in your list of sound devices just like a headphone socket) will accept a digital audio signal from a data program, pass it down an imaginary cable, and the signal will appear at the other end from an other virtual audio device..

VB Cable send you three, which appear in Windows as "VB Cable" "VB Cable A" and "VB Cable B". Each end of each cable shows up as in input and an output device in you list of sound devices in Control Panel. You install them on your PC, but it is best to right click on them and use "Install as Administrator". Then you plug one into your program for input and one for output. At the data program end I always use A for input, in case I get confused (!). You can see them in the WSJT-X photo above.

The other end of the cables goes into the PowerSDR by following "Setup" then "Audio" then "VAC1".
From the PowerSDR point of view you are at the other end of the cable, so A is now the output and B the input. You have created a virtual audio cable and connected them up. Now you need to set the levels, which involves twiddling sliders. You will find that the audio sliders appear when you select a digital mode.
You can see that I have saved these audio settings under the name "HF wspr 1". You can have several saved. Note also the sample rate 48000 and stereo box unchecked. You can use various rates in your data program, audio cables and PowerSDR, and they will convert at each stage BUT, this can cause slow operation. I found that up to 4 second "latency" arose when Windows had set the VB Cables to 44100 Hz, Power SDR has set the rate to 48000 and WSPR works at ... (whatever rate it does which I think is 11025). So set the VB rate to 48000 Hz (DVD quality) by selecting "Start", "Control Panel", "Device Manager", "Sound", double click the icon of the cable outputs one at a time, click "Advanced" and you will probably find that they are not set to 16bit, 48000, DVD quality. Check both cables and both input and output to make sure that you are set to 48000. This is necessary because Windows sets the cables to 44100 automatically.

This is much the same procedure for other SDRs and other data programs. HRD is a bit odd as it allows you to use basically a rig control system (HRD itself) to piggy back a data program (DM780). That works fine but it can introduce even more latency, rate changes and so forth. I have been able to run DM780 independently of HRD and drive the Flex direct, which reduces the latency a lot, but it uses PTT control so there is no CAT. Maybe since I resolved the 48000 Hz rate issue with VB Cable this will no longer be necessary. We shall see.

Anyway, there you are. What a palaver! Still you only have to do it once (I must have done it dozens of times after re-installing Windows etc). However, once done it works very well indeed.

Have fun.

73

Jim
GM4FVM
P.S. Thanks to countless people for coming up with the ideas set out here, especially on the Flex and WSPRnet sites.

Monday, 6 April 2015

Just a moment of early Es.

I was pleased to read this posting by Anthonie, NL8992 on the WSPR chat board:-

I had the pleasure of copiing SQ85PZK in FSK441 in full periods during what appeared a 2 min Es opening on 4meters!!

 I saw that too.


You can tell that this was Es because the signal held up for a long time - in the bottom trace almost right across the 30 second window. Not the usual meteor scatter blip. Also it gently rose and fell again, unlike the sharp start to meteor scatter blips.

I had a few doubts, but Anthonie knows a lot more about propagation than I do, and two sources is proof for me!

Hooray! Es is here this year (well, just).

Historically it was always the Es from Poland which marked the start of the season. In the dark old days before the Berlin Wall fell, we used to hear the signals of Radio Gdansk pumping out martial music on 70.26 - it was on wide FM and we were on AM so it sounded terrible!

I am still not ready - only 20 watts on 6m. Can we survive this emergency if the Es arrives? I will need to fix the old Bremi valve linear to get my 6m signal going again. Oh dear. I will need to wind a new anode choke. I am too old for that type of thing, with my bi-focals and so on. I will need a magnifying glass. Should have learned by now, having blown up two 6m linears in a row.

Today I worked SP9HWY (JO90nh 1538km) and SQ85PZK (JO92ga 1416km) on 4m meteor scatter, G4BWP (JO02ph 452km) on 4m tropo  and G0KJF (IO80mv 554km) on 2m tropo. While none of that was Es, the signs are good.

Who said the bands are always better at the weekend, especially a long public holiday weekend?

73
Jim
P.S. I also heard some SSTV or fax or something on 70.232. Now I wonder what that was!

Sunday, 5 April 2015

Bands are better at the weekend

It is oft said that the bands are better at the weekend. That just means there are more stations active Friday to Sunday (or Monday for this week's European holiday).

Some good stuff so far this weekend.


I was doing my beacon search and GB3NGI was there strong as usual, but I FINALLY found GB3WGI.

OK, this is a beacon running 100W into a pair of 6 ele beams and only 396 km away in County Fermanagh, so you wouldn't think it would be that hard to do, even with a 10 ele tiddler at this end.

Nevertheless, I had never heard it before.

Maybe that is because this beacon is specifically designed to be heard on the far side of the Atlantic Ocean, so it is not exactly optimised for Scotland. Basically, for a UK beacon it could not be harder to hear from here.

So, it is done and another one is crossed off the "to do" list. In reality it shows that conditions are pretty good towards GI right now, so there must be some tropo about. I am hoping that tomorrow and Tuesday should be good too, based on the atmospheric pressure chart.

There was an RSGB 4m contest today which I almost forgot about. I was blasting away calling CQ on meteor scatter when I noticed that I was hearing the SSB of a certain station who reckons he is a 4m contester. I was beaming East and he is South of me, but all the same I heard him clearly. I just wish sometimes he would hear me. Or rather I wish he would LISTEN for me, as I reckon that listening is not his best skill. Eventually he might find that trying to work on the meteor scatter frequency used by almost everybody to call CQ will limit his results, even if he cannot hear us all blarging away on 100watts.

I came on for the last ten minutes of the contest. I managed to work G3TCU/P in IO91rf, 524km, Eddie, G0EHV (nearby) and David, G4ASR, IO81mx, 434km. The usual suspects. Not bad for ten minutes work.

Then I went back to calling on meteor scatter and worked OZ1JXY. Henning is a regular, despite the fact that according to the book he is too close to me (734km) and in the middle of the day (12:42) we should not be able to work. But we can. So much for the book.

I have just left the VLA-150 linear in the corner, so I am restricted to 20 watts on 6m for now. It smells so awful I do not want to open it.

73

Jim

Tea .. and then the linear blew up.

I have had a very frustrating few days.


Friday was a nice start with morning tea with Doug GM6ZFI and Derrick GM4CXP. Alongside the usual banter, Doug offered to come round and try to solve my height access problem with the 6m beam. Seemingly it may involve moving the top bracket downwards, which looks good to me.

If "morning tea" gives you the impression of Darjeeling, cake, and buns, it was in the cafe of Pearson's Garden Centre and Coal Suppliers in Duns. I had a diet coke and a bacon roll. Not grand, but very nice all the same.

It is nice to have "tea" with a few ham colleagues and swap stories and gossip. I used to go to a radio club regularly, but they were very stuck in the mud and didn't really like my ideas, and who can blame them for that? So I left. I still go to the (much better) Cockenzie and Port Seton club near Edinburgh when I can, but it is a long drive.

Then I was back home and I was running the Flex 1500 on WSPR. I find the 5 watts is a bit low on 6m, and I was running about 20 watts using the RM VLA150 linear amplifier. Although this claims to be able to run well over 100 watts, I find it struggles a bit to top 90 watts with the 5 watt drive available from the Flex.

Anyway, it has a nice big fan on top, and with a capable heatsink it is no danger of overheating...

I noticed a strange "hot" sort of smell lately, which is never a good sign. I had it before when the power distribution system for the 12 volt accessories went off beam and some supply wires heated up. I guessed it was this again and hunted about for a hot DC supply wire (later I ordered a new, multi-fused, 12v distribution system as the current one relies on one fuse).

This smell was like hot heat-transfer compound, as used in a PC processor to provide a path for the heat from the chip to its heatsink and fan. You know, if you don't have enough compound and the system works hard. You get the smell of the heat transfer compound which is a telling you something is wrong.

Hot electrics is never something I like. While I was hunting about with the fans and things, the smell changed to a nasty acrid smell of something transistorised having given up the ghost.

It turns out that my RM VLA-150 has gone almost silent key. It was not working under any strain. I have an idea that one of the power transistors has over heated and blown. It could not have been overdriven as the Flex cannot manage more than 5 watts whatever you do. Maybe that "hot" smell indicated that there has been a problem brewing for quite a while. Anyway, curtains for now and I need to find out what has gone wrong. I think I will be needed a new PA transistor.

I say "almost" gone silent key. It still produces about 30 watts for a 5 watt drive, so perhaps one device has gone. More heat transfer compound next time. Could it be that RM amplifiers are not brilliantly made and not properly quality checked? Surely not! I see that the VLA-150 is not available any more.

I might say that 6m amplifiers have not been a great success for me. I have a 6m conversion of a Bremi CB valve amp which overheated and melted the anode choke. Now the VLA-150 has gone too. I have lashed up a (not linear!) amp to get me by ~ 20 watts and always use a low pass filter! I could get more power out of this using it in Class C mode, but I might want to try it on SSB so it needs to be more or less linear.

Is 6 metres doomed from here? Why have I had repeated problems with the Bremi, the RM amp, the Flex, the beam ... ???

There is something wrong with things on the Flex front too which I will detail later. Software seems to be the problem, so I should be able to fix it here myself.

The blown PA and the software issues have taken up about 75% of the weekend. Grrr.

73

Jim
GM4FVM

Thursday, 2 April 2015

Targets,more targets.

Is it important to set targets. "If you don't measure it, it doesn't get done." Or so they say. It is also possible to end up striving for the target and forgetting what you are doing it all for, which is in this case, my hobby, radio,

Anyway, whatever the logic of it all, at this time of year I review what I have done and what I hope to do in the next year (if I am spared!).

Review of last year's targets (April 2014 to March 2015) and a look forward:-

Ten metres.
I started off last year with the still big "undones" on ten metres. Relating to PSK/JT65 and JT9 data modes, from here, I had just worked China, but was still missing India, Pakistan and New Zealand, amongst other countries. YV1DD in Venezuela was a nice new one, as was DU2/WA8UGN in Philippines. I am still missing confirmation of 20 US states on eQSL although I passed the 300 prefix mark. I did not manage to work India, Pakistan or New Zealand.

Frankly I do not bother much with chasing after things on 10m. If I had wanted all States confirmed I might acutally send out some cards or eQSLs. I don't send any cards on my own account, I ony reply to the ones other people send me. And anyway, if I really wanted records I might not start on 10m with JT65. And I might dig my beam out of the garage and use it instead of an ex-CB vertical.

So for next year, India and Pakistan remain on the target list. At least I heard them last year, whereas I have neither heard nor worked New Zealand, on any band, by any mode, from anywhere, in my amateur career.

For WSPR next year I might try to beat my 1mW best DX. So far that is to 4X1RF.

Basically 10m remains a band I love to follow for clues to propagation, and not a band to pursue in its own right. Pity that, but I only have so much time.

Six metres.
Last Year's target was to beat my best DX record which was 3621km to VO1SO as long ago as 18 June 2011. That is crazy as my 4m best DX is already 3276km, and 6m should be easier. Anyway, 3621km was well beaten by working WP4JCF on 17 June 2014. So, 6737.9km (more accurate using the 6 digit locator) becomes the target to beat. I suspect that will take some time...

That QSO, together with others like one with Azores on 4m the previous year, remind me how glorious VHF can be, when it works. Band quiet, nobody there, and then suddenly just one station - rare DX! Remind me of that during February doldrums.

Target for next year - just one - beat 6737.9km.

I do not really count countries or squares on 6m. Maybe I should.

Four metres.
There the target was the same as in previous years, two new countries and 5 new squares. The result was no new countries and 18 new squares. 6 of those squares were worked on 17 March alone. With 4m I am relying on new countries appearing. Next year we have Malta and Lithuania for the first time. Lithuania should be pretty straight forward, but Malta is maybe too far for normal Es. Also standing out as needing to be done are Greece (all four types), Macedonia, plus a lot of rather small places such as Ceuta and Melillia, Guernsey, Jersey, San Marino, Market Reef, etc. The larger places are difficult distances, and the smaller places have very little activity.

So the target remains 2 new countries and 5 new squares.

What I really need is France or Sweden to open up 4m. I am happy to have any country, but you don't learn much about propagation listening on a band which has large gaps in the amateur population. So here is a target I have no control over, let us please have France, Sweden, Switzerland, Austria and Latvia added to our 4m roster. Is that too much to ask? Probably.

Two metres.
No specific target for 2m in recent years. Best DX is EU7AA in Belarus, 2070km, but that was set back on 10 June 2011. Incidentally, that was within a week of the 6m DX record, which lasted for three years. Now that I am more active on meteor scatter I may work some more in future. The time to break that record is surely next year.

So for next year the 2m plan is to increase the best DX beyond 2070km.

Summary.
Last year was not a great year. No New Zealand on 10m, no new countries on 4m, nothing much at all on 2m. There was one stand-out contact, WP4JCF on 6m. I do hope that next year will be better. Declining sun spot activity may cramp 10m, but I am now better set up for meteor scatter on the VHF bands. So we shall see. The one dark spot is that I have lost 1dB gain on the 6m antenna, but then I have gained 3dB on the 4m one. And the 2m one has new low-loss coax and it may yet get a work over on the gain front.

Ask me how I got on next April. If I have not gone QRT with frustration, I hope I can report that it has gone well.

I'll keep you posted as I go along.

73
Jim

Wednesday, 1 April 2015

Tennamast, my best accessory.

I seem to be having issues with checking out the radio insurance market - more on that later. I would like to share my happy experiences, but it is just a thankless chore, to be honest.

But it got me making an inventory of all my accessories. The best one I have is my Tennamast.


I have always wanted one of these, but it only arrived here about 5 years ago. Mine is the "Adapt-a-Mast" tilt-over type one, which is fixed to the house wall by extremely sturdy brackets. That is the safest method as far as I can see. No climbing, and the house offers wind protection.

I have no connection with Tennamast, I just like the product they made which I bought.

Tenna have a range of masts available, and they will ship them to many places. They are based in Scotland and when I spoke to them recently they had sent one to New Zealand. I am not surprised as they are a very effective product. I would say that, pound for pound, it is the most effective piece of equipment in my station.

The Adapt-a-Mast which I have is 7.6 metres. That is the smallest they sell. They recommend maximum height above the rotor of 2.1m, so 7.6+2.1 = 9.7m to the top, plus the rotator and lower mast, which makes about 1m possibly. Mine is about 10m as I do not use the full 2.1m above the rotator. At that maximum height the antennas cannot be seen from the road outside our house when the mast is lowered.

Also available from Tennamast is a rotator cage. I have recently bought a rotator cage but I am not using it yet.

You can also buy a 10m version of the Adapt-a-Mast. It is mainly intended for mounting on two storey houses. It might go on a gable end (I am not sure about this) but it is not what I am after. The extra height would help, but I am happy with what I have.

The shorter Adapt-a-Mast I have is a two section mast. The two main sections are square section alloy tubes which fit into each other. So the mast is raised and lowered by a winch (mine also tilts by a winch - see later). The smaller section sits inside the larger section, and is then pulled out to raise the mast.

Tenna make the Adapt-a-Mast in both non-tilting and tilting sytles - the non-tilting is cheaper as you do not need the winches, pulleys and wall bracket needed for tilt. As I have never been a good climber I chose the tilting one. Now I am a worse climber than before, so I need the tilt even more.

The standard winches supplied are good enough, but I opted to upgrade mine. You have to release the ratchet on the Dutton-Lainson winches to lower the mast or tilt it. I feared dropping the winch handle as it lowers, though that is pretty unlikely. Tenna offer braked ones, but they need back pressure to operate. Yes, they will brake, but only after a short fall or tilt. Yep, sure that is fine, but I installed a pair of Dutton-Lainson worm gear winches instead.

The point about worm gear winches is that they stay wherever you leave them - half wound up or fully wound up or wherever. They were not cheap, but they are very effective. No ratchets now. Doug, 2M0LAT kindly made a couple of hex bolts which fit into my power screwdriver and drill. Now I can wind the mast up and down, and tilt it over and back, with the battery powered drills. Simple. Doug also drilled out the winch frames to fit the Tenna brackets. Job done. Electric winches with no mechanics outside to rust, as the drills stay nice and warm charging in the house.

The second photo shows the base of the mast, lower mounting bracket, winch for raising the mast and at the back secured to the wall, winch for tilting the mast. You may be able to see (click on it to enlarge) the rectangular clamp which holds the mast steady when not tilted over. So in normal use the mast is held on the backets and not supported by the tilting winch.

I always lower the mast when not in use. My neighbours should not need to look at it all day. Also, it protects it if the wind gets up overnight. Somewhere I saw a Google Streetview of our street with an image of the mast raised in the photo. They must have surveyed the street when it was in use. I only tilt it when I am working on the antennas, so it stays fixed to the wall by the brackets, lowered, most of the time.

Fixing for the mast is by the backets into the house wall. Each bracket is held by two expanding masonery Rawlbolts, four in total, plus the ground hinge fixing. When it tilts, the bottom hinge supports it. The bottom hinge is bolted into a buried concrete block, also fixed by four Rawlbolts. I do not remember now, but I think it is only a half metre square of concrete as the mast is supported by the tilt winch when tilted over. I bet for free standing masts you would need a lot more concrete - a square metre at least.

It was installed by two of us in a day's work divided into two sessions. Half a day to dig the hole and cast the concrete, then half another day to assemble it. We left the concrete for a few days to "go off" before doing the second half day's work. It arrived by truck but I could lift it on my own and carry it round the house.

Tenna also make free-standing versions of their masts, which tilt from a winch on a ground post. I did not want one of those for all sorts of reasons. I would guess that freestanding Tennamasts they are easier to manage than the classic trianglar lattice masts, but maybe they can carry a bit less headload than the heaviest lattice mast.

So there it is. At the moment I have a 6 element 4m beam, 2m dipole and a 10 element 2m beam on it. At various times I have had a two element HF mini beam, verticals, and assorted beams, and the joy is that I can tilt it over and shuffle them around. My antennas are changing regularly. It takes about 10 minutes to undo the brackets and tilt it over.

There must be some drawback. Not really except maybe that in the wind it rattles and groans a bit. This sound is the inner section bumping against the outer section. They have to be loose to allow for extending the mast. I do wonder though, could someone not design an angled wedge on the inner section which would fit against the outer section when lowered and hold the thing more firmly? But that is the sum total of my doubts.

There is of course the price to consider. It cost me about £650, whereas I could easily spend £2000 on a linear amplifier. That would add nothing to my received signals. By allowing me to put up better antennas the Tennamast let me improve both my received signals and also the signal arriving at the other end. Better value than a linear  I think. I have linears too, but they are not a patch on this thing.

I will put a link to Tenna's site on the right of my blog.

73

Jim
GM4FVM