Jealousy between sets
 

I like to think that I am a totally rational person but just now and again I tease myself with irrational thoughts. This happened today. I was running three sets simultaneously and adjusting the relative distribution of aerial signals for best performance. All of a sudden my HMV901 suffered a line collapse reducing its width to about 1". This set is normally very stable and reliable but here I was running it alongside others competing for its signal. Clearly a case a jealousy!

My first thoughts were to swap the line oscillator valve and the output valve but no change. Then in my depressed state thoughts turned to the worst possible failures. So I checked the output transformer and it looked OK, next the oscillator transformer and things were looking up for it was OK too. Must be the output anode choke? Nope, well that's good let's check the anode feed to the oscillator. Great! The 500K was open circuit. :) Raking around I found a suitable dog bone and gathered my tools and soldering iron at the set.

Having extracted the O/C resistor I then looked around for my replacement. I looked absolutely everywhere but it was nowhere to be found. After half an hour of fruitless searching I eventually discovered that when moving things in position I had placed the Anglepoise base on top of the resistor.

Well you might have expected things to come to a rapid conclusion after all that, but no. The combination of getting the Anglepoise to illuminate the spot and messing with head magnifiers and shakey hands meant that it must have been about another hour before I actually managed to solder the thing in place (badly).

However, at least the set now powered up with the correct width. Perhaps I'll think twice about sharing its aerial signal with other sets from now on. ???

Peter

Re: Jealousy between sets
 

It'll get its revenge on the other set, just you wait. There will be a part II to this story.

David

Re: Jealousy between sets
 

David, You clearly know me too well!

I am bound to have placed reliance on unreliable components or failed to have soldered something properly in the other sets too.

Peter ;)

Re: Jealousy between sets
 

That may be too simple. It probably has a pre-existing issue that it's been cultivating for several decades and is holding in reserve, ready for 'just the right time'.

Like the laws of thermodynamics show that entropy increases relentlessly, and that you can only get a momentary seeming reversal at the price of a far bigger hit, I find that embarrassment obeys similar laws, and for me always tends towards a maximum.

Reckoned you soldering was always OK, but then again, hanging upside down and working in the shady depths of a pre-war telly can put anyone off their stride.

David

Re: Jealousy between sets
 

This can account for a lot. In the early '80s I discovered a long-forgotten Baird T5 in the basement at BBC Wood Norton (where I used to work). I spent an entire lunch hour with my head inside the set, just to breathe in the untouched 'pre-war television set' aroma. I never was the same again.

Steve