Saturday, 11 March 2017

Non-aurora, Mad March optimism and computer maintenance.

Despite the fact that there has been no significant radio aurora here for almost six months, conditions have been close to auroral several times.

"Close to auroral" is a common condition here. Solar wind speed raised, Bz minus and fluctuating, HF disturbed ... even beacons heard aurorally, ... but no contacts.

Isolated periods of Winter Es are often associated with auroras, and often called "Auroral Es". I had a hunch that there might be some AuE activity about yesterday and put the 10m WSPR on.

Auroral Es noted at GM4FVM on 10 March 2017

Auroral Es openings are generally best to the North from here, so OK2SAM was unexpected.

Classically I expect AuEs directly after an auroral opening, but of course it does not always happen. However, I have noted AuEs quite often after "close to auroral" conditions. As I discussed last year, isolated Es openings during Winter appear to be highly correlated to increases in X-ray flux, which is an effect noted during auroras.

I read recently that a seasoned observer was trying to link "Christmas" Es to cold weather at his address. I doubt it, as Es conditions exist from 500km to 1000km from the stations who are actually in contact, and the weather is usually different over that distance. "Christmas" Es occur most years, but then so does cold weather in "These Islands". This does not necessarily mean that the two are linked.

Another cause of Winter Es may be "Cosmic Rays". These are not rays at all, but the term is usually used to mean charged particles from outside the Solar System. Many can be remarkably energetic, far more powerful than anything created in the (vastly powerful) large hadron collider at CERN in Switzerland.

When Cosmic Rays encounter the Earth, thankfully, they generally collide with particles high in the upper atmosphere. These collisions result is intense ionisation, and the creation of a large number of lower energy ions, which in turn collide as they reach lower levels in the atmosphere and the result is a "shower" of ions which can cause Es. So so we think.

Because the Cosmic Rays come from outside the solar system (maybe from other stars or even star collapses and super-novas far into deep space) they are not confined to our Summers, as is the case with conventional Es. Beware though that some people will use the term "Cosmic Ray" rather loosely and include in their meaning particles released from the Sun. Beware also those who will tell you that Es activity is related to cold weather at their house.

I  have written a long piece about radio auroras which I have not posted. I have been waiting for a radio aurora to use as a good example. As no example has turned up, I may break it up into pieces and post it here over the next few months. It is not so much about the scientific process of auroras, rather it is about how to predict (!), understand warnings about, and operate during, radio auroras.
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March is another dull month in the VHF calendar. Not as bad as February though, as I find that meteor scatter activity begins to pick up. Whilst auroras and tropo openings are unpredictable, the annual Es campaign is now just beyond the horizon. Of course I will fret when we get to the stage where 10m has Es but there is none yet on 6m or 4m. Expect a posting about the dates of the first Es over the past several years, and various other anxious remarks. But, so far, Summer Es has always arrived eventually.

Thinking of the first date for Es each year reminds me of boring class in Geography in school, tracing the northern-most extent of olive growing, which was represented on a neat map. If only I could do an Es map like that.

Other things to do in March include keeping in touch with people. I was glad to meet Bruce, GM4BDJ, for a coffee recently. We seemed to have a lot to talk about, and the garden centre sold two coffees and two hot chocolates to these two old duffers who sat and talked for over 3 hours. Not a good sales rate for them, but we had a splendid blether.

It seems strange to me that a hobby like ours, which is after all about communication, can be so solitary. We can sit here with our microphones and feel quite isolated. Graham, MM0XXL, has organised a series of meetings at his QTH where various local amateurs have been able to swap experiences. This is what radio clubs are for, though sadly these clubs often seem to get bogged down in personality clashes.

So I think that we need to get out and meet people, even if on an informal basis.
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All that talk about computers last time made me think that it would be worth showing you all a photo which should shame me. I will show you an "after" and a "before" shot ....
My PC main processor after cleaning
My PC main processor before cleaning
Now, I did think that the operating temperature of the main processor was getting very high, very quickly.  However I was not expecting it to be completely blocked with fluff. This is what happens when you take a machine with a fan, put it out of sight under a desk sitting on carpet, and forget it for 6 years.

Also discovered on this inspection was the fact that the extra case cooling fan which I installed did not seem to be working. It is temperature sensitive, but it should turn over at start up. Closer inspection showed it to be seized solid. It was impossible to free up, and I had to throw it in the bin. There was not much fluff in it of course.

A cautionary tale here. In this case no damage resulted because I caught it on time. But just think about any rig you have with a cooling fan. Many modern rigs allow you to monitor an internal temperature. For example the IC-7300 can display the power amplifier temperature, as well as having an over temperature warning. If you have temperature sensing fans, do they come on more often than they used to? What about your power supply units fans, are they on for a lot of the time? Remember too that fans can seize, so if it gets quieter, that too can be a warning.

Is it not time to open things up and have a good rummage around any fans you may have? Time for a thorough vacuum?

Maybe checking the fans is a March task, or maybe they need more attention than that ...

73

Jim

GM4FVM

1 comment:

  1. I used to work in a place with a large clean room, and the computers in there were spotless even when six years old, contrasting with those in the offices that were full of detritus after 6 months. Of course things that depended on cooling even in the clean room still failed, fan bearings seized, water pumps also, water got algae growing in it etc. I try to avoid forced air and water cooling to this day.

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