Sunday 10 January 2010

Another anti-Linux rant, I'm afraid.

Today, for reasons I won't bore you with, I had to move my "Linux box" to a different location, and the new location demanded a different mouse to the one I was using previously. Naturally I planned to use the Linux GUI rather than the command console.

The first mouse which came to hand happened to be an old but nice Microsoft serial mouse (remember those?).

Well you would think setting up Linux to work with a serial mouse would be easy, wouldn't you?

Wrong!

I did a fair bit of research on the internet, noting from that others had had similar problems.

None of the suggested remedies I tried worked. I gave up in the end and located a spare USB mouse which worked straight away.

OK, so serial mice are definitely "old school", but I would have thought that there were a fair few in use around the world.

Linux really is PANTS!

The Noble Art of Blogging

I suppose psychologists have a number of theories about why people "blog", and I have often wondered myself. This morning I was following a train of thought in my head as a result of which I looked up something on Wikipedia (I don't think I need to elaborate about what and why ...). It happened to be about a well-known person of whom I knew a fact that the average person would not know, owing to the fact that the "celebrity" in question had a descendant with whom I was acquainted in my school days.

As one does I followed a "web trail" of links and cross-references, and ended up reading someone's "Blog" where quite detailed and intimate (not in any way in the salacious sense of the word) references were made about my former school-mate. At this point I should say that I wasn't a close acquaintance but, an at least we would have been on "first name terms".

Now it so happens that my former school mate deceased prematurely in her forties, a few years ago. I was already aware of this fact, but the "blogger" in his column made me aware to a certain extent of some of the reasons why this person's life came to a premature end. Part of that story actually had its roots in our mutual school-days and, naturally, it struck a nerve.

As you can imagine, this was quite a harrowing experience, but it did make me wonder about why I find some blogs so interesting.

I now think it is something to do with one person articulating in the form of the written word (unlike in the printed or officially published press, there is no financial or career motive for writing down what one thinks) their thoughts, observations, etc, and the reader reading those thoughts and observations and thereby giving their own thoughts and observations a context. Possibly rather like having a conversation with someone you have never met before, but whose point of view you find rather interesting, even if you don't necessarily agree with it.

One of my personal philosophies is that I don't mind too much being wrong about something.  I will admit to prefer being right to being wrong, but accept that that one cannot be right all of the time.   However, I usually enjoy the argument, and if the argument proves that I am wrong, then so be it!

Just a thought ...

Saturday 9 January 2010

Classic Hybrids and WSPR and ...

A very interesting thread has sprung up on the "Fox Tango" Yahoo group prompted by an Italian amateur with an interest like mine in classic hybrid radios - in his case a Yaesu FT-901.

Apparently his radio developed a couple of faults, in particular the failure of the 6V regulator which feeds (inter alia) the DC supply to the VFO circuit.

Not surprisingly the original IC regulator is obsolete, and having nothing else to hand he replaced the faulty one with a bog-standard 7805 unit, and even though the previous 6V supply is now only 5V he claims that the VFO is now "rock solid".

You will realise from my www.g4fui.com web site that old radios are also an interest in mine, and it so happens that over the last couple of days I have been looking at the performance of my own FT-902DM and in particular the VFO stability (or rather the LACK of VFO stability) of this particular set.

I had been musing upon the supply regulation to the VFO as it appears that the real problem is that the VFO drifts as the set warms up, and as it is a bulky, heavy radio it really NEVER warms up properly (not in a reasonable operating period anyway), consequently it NEVER stops drifting.

It drifts so much that you couldn't use it sensibly for a mode such as WSPR.

I had come up with a theory that the original regulator, which claims to be a "low drop-out" device (ie it will work with the input and output voltages relatively close together, really was working just TOO close to the wire with only a theoretical 8V input being regulated to 6V out, such that the thermal changes in the environment were affecting the output volage to a significant extent.

Having a bunch of 7805s kicking around in my junk box, I just might give this a try. OK the output voltage may be significantly lower, but assuming any static frequency change can be trimmed out, the extra volt of dropout voltage, coupled with a more modern device may well make a noticeable difference to the performance.

Another contributor to the same thread suggested putting a diode in the common lead of the 7805 to lift the output voltage, but I would be tempted to try it without as (a) it would reduce the dropout voltage and (b) I suspect that the temperature coefficient of the diode would exacerbate the drift problem. Having said that, it would be very interesting to find out!

Another alternative would be to fit a 7806, and possibly take the input voltage from somewhere else, eg a 12V or similar rail in the radio.

Another item added to my "to do" list, so watch this space!