Here is a photo of the battery wiring.
I went round to see Unrealdave today, to rummage through his boxes of potentiometers.
I couldn't find what I was after loose in the boxes but Dave had a piece of equipment he was dismantling which had a 50k Colvern pot in it, which he kindly let me take home to rob the pot out of it.
Back home, I dismantled the Colvern pot and the resistance track came out nicely.
I wrapped the ends of the track in some polished copper to help hold the wire in place.
It was a very tricky job fitting the new track in the old reaction control body.
The new track was about 3mm less in depth, so I had to make some spacers to hold the track up so the wiper would reach it.
That was tricky enough, but then I realised I had to drill a hole through the track wire and former at the centre of the crescent so that it could be bolted to the brass plate which shorts out half the track.
I ran some superglue over the lower edge of the track to hold the wire securely,
I wrapped another strip of thin copper around the point where I would be drilling and fitted the track back in the body and drilled in using the screw hole as a guide, that went OK.
The original pot wiper was rather large about 6mm wide,
this seemed too big so I went and made myself a new wiper bush from brass rod which was only about 3mm diameter and fitted this into the wiper arm hole, then I soldered it in place.
At one time it seemed like a simple task to take a track out of one pot and fit it into another. In reality it was far from it, this job was not an easy one, it took the best part of 4 hours to complete, but I now have a 22k pot mounted to the reaction condenser to act as the reaction/volume control.
I dont know what it is going to work like, but I have done the best I can to get the pot working again, we will see tomorrow when I fit it back into the radio and sort out the power supplies.
Mike
I went round to see Unrealdave today, to rummage through his boxes of potentiometers.
I couldn't find what I was after loose in the boxes but Dave had a piece of equipment he was dismantling which had a 50k Colvern pot in it, which he kindly let me take home to rob the pot out of it.
Back home, I dismantled the Colvern pot and the resistance track came out nicely.
I wrapped the ends of the track in some polished copper to help hold the wire in place.
It was a very tricky job fitting the new track in the old reaction control body.
The new track was about 3mm less in depth, so I had to make some spacers to hold the track up so the wiper would reach it.
That was tricky enough, but then I realised I had to drill a hole through the track wire and former at the centre of the crescent so that it could be bolted to the brass plate which shorts out half the track.
I ran some superglue over the lower edge of the track to hold the wire securely,
I wrapped another strip of thin copper around the point where I would be drilling and fitted the track back in the body and drilled in using the screw hole as a guide, that went OK.
The original pot wiper was rather large about 6mm wide,
this seemed too big so I went and made myself a new wiper bush from brass rod which was only about 3mm diameter and fitted this into the wiper arm hole, then I soldered it in place.
At one time it seemed like a simple task to take a track out of one pot and fit it into another. In reality it was far from it, this job was not an easy one, it took the best part of 4 hours to complete, but I now have a 22k pot mounted to the reaction condenser to act as the reaction/volume control.
I dont know what it is going to work like, but I have done the best I can to get the pot working again, we will see tomorrow when I fit it back into the radio and sort out the power supplies.
Mike
