Friday 2 July 2021

Summer is here (I think), and why are my reports always worse than theirs.

Ah, Summer.  Midges, flies, wasps, ants, too hot to sleep, sweaty days, noisy neighbours at stinking barbecues, traffic jams, cafes full of day trippers, grass cutting ... don't you just love it?

No, I do love it. There is the Tour de France, Cricket, long warm evenings, and relaxing beside the radio.

I know when it is Summer because the local flocks of alpacas sit down in the field rather than eat the huge banks of grass which the warm weather produces.

The Ayton Law alpacas, a recurring topic in this blog

They have been shorn again. This seems to happen a lot but early July seems a bit late to me. I thought they only gave up their fine wool once a year, but what do I know?

I find that my knowledge of small domesticated camelid shearing is much like what I know about radio propagation. I do not really know very much. Clearly they are both complicated subjects. However, I can observe what is happening, and maybe I can learn from that experience. These things can surprise me but they are very common so I should take note.

I mean, what is unusual about alpacas? It all just happens whether I take note or not. Like radio. So take note and learn from what you cannot change.

On the other hand do I actually need to understand the processes involved? Is there not a chance of just looking and marvelling without really comprehending in detail what I observe?

Perhaps there are some things I might never understand.

Hmmm.

Anyway, June has ended with a long-ish Es event on 2m and I managed to get into part of it. Then there was also a fairly long tropo event which I managed to participate in for most of the time.

It all brought a reasonable map for June on 2m

2m contacts at GM4FVM during June 2021.

As usual, click the image to enlarge if necessary.

The Es openings accounted for my contacts into Spain and Portugal, while the tropo explains those across the North Sea. What I missed was an opening into Central Europe. Ah well, there is always next year (maybe ....).

Basically, it is astounding. 13 countries in 44 squares in a month with no EME or meteor scatter. All Es or tropo. Remarkable. When I was G8JWG I would have doubted such a thing was possible, never mind that I would do it without trying very hard. Plus I was away for a number of days during June.

On 4m I might rue that fact that I "ONLY" worked 19 countries, down from 25 in May. (But 25 is a huge number, Jim, so it was bound to be less the following month)

These are the sorts of figures which amaze me. I know I keep banging on about my station, but it is not in the superstation category. I do not want a superstation. 7 elements on 2m where I have just over 200 watts, and about 100w on all the other bands. Antennas just sufficiently high to clear the roof tiles.

Enough already.

I had some email correspondence with GM3PPE. Mike is always interesting. He was raising the subject of antenna height gain and the possible relationship between antenna height and differential signal reports.

Spurred on by his line of thought, I did some analysis on a random (?) slice of my log book. This confirmed my feelings, which mirror Mike's, that I give better reports than I get. The section of log is posted below but you will definitely have to click that one if you want to study it (personally I wouldn't bother to study it if I was you).

Random slice from the GM4FVM's VQLog log book

It has changed slightly from when I did the calculations - one doubtful contact has since been confirmed. I disregarded the doubtful ones. "Doubtful" and "failed" contacts appear in orange, but sometimes doubtful ones get confirmed later.

And, yes, EA4T was a treble, and he called me to complete it so it is not just me who chases these things.

Anyway, when I worked it out there were 43 valid entries then and the total was 28 times I gave them higher report and 12 times they gave me higher with 3 exactly the same. So, yes, I do give better reports than I get.

That does not give the full story. I gave two of those 34dB better than they gave me. Two of them! The highest the other way was someone who gave me 15dB more than I gave him. 

I remember the few instances of big numbers in the different reports. I forget the many smaller differences. When I average the whole thing out, even with two 34dBs in there, the difference taking all 43 entries into account is 3.5dB. While the massive differences might have caught my eye, the reality is not so bad. 

My final conclusion after all this waffle is that there is evidence that I give better reports than I receive. I doubt if my antennas, or my lower power or my titchy masts, are to blame. Many stations have higher noise levels than me, some use lossy analogue audio connections, and some use a lot more power than I might expect.

Then there is rapidly changing propagation. But would it always change to benefit the other station's reports? That is a mystery just like alpacas.

Perhaps nobody knows.

Or perhaps it is just not worth finding out. 

Or maybe I am happy with the results I am getting (see map/log).

Apparently the BBC do something to inform the public about alpacas. I have been told to watch "Nuzzle and Scratch". Seemingly it is about my level, or so Mrs FVM says.

Not sure what that is but I must get on to finding out.

Or not. 

I did mention I am paranoid, didn't I?

73

Jim

GM4FVM

3 comments:

  1. You definitely are paranoid. I wouldn't care about the reports. As long as reports are exchanged the QSO is valid. I recently got a +23 report. I really don't know how this is processed? I never ever seen a higher report as +10 from my station. 73, Bas

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  2. Ah Nuzzle and Scratch who are “Alpacas from the Andes with hooves instead of handies”. I used to know the whole theme tune….

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  3. Bas, I agree with you.
    I do not believe that "decibel above the noise" reports can ever be accurate(given that they are an estimate across an imaginary 2500hz filter width) in the sense that they cannot be compared between stations.
    It is odd though that they are generally stronger in receive - for me anyway. My own theory is this is due to a combination of the variations between SDR and superhet base noise levels, preamp noise factors (where used) and some stations using direct digital paths while others use audio links of doubtful performance. Plus random QSB.
    I have never trusted S-meters either.
    As you say, as long as reports are exchanged the QSO is valid. I have seen one definition that all that is required is to exchange call signs plus some "information" must have been exchanged and confirmed as well. Moonbounce QSOs generally do not include reports but cryptic shorthand information such as OOO, RO and RRR, and they are regarded as valid. In any case, JT65 reports are constrained to negative values and compressed above -10dB to suit, yet moonbouncers still quote them on various sites. Not that mine ever get as high as -10dB (boo-hoo).
    Gavin. Those are the very ones!!!
    73 Jim

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