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Niechcial,Steve · 17th Dec 2019, 3:21 pm

I've now had time to go back to this set. The LOPT is away with Mike Barker for rewind, but there is plenty I can do in the meantime. I've put new aquadag on the tube and set it aside for the present. Having the tube out makes the whole chassis much more accessible.
I've started to investigate the issues around this set seemingly being hard wired for 625 only. When it left the factory as a convertible set it was fitted with a partial systems switch which switched the timebase functions only. The converter kit then came with another few switch wafers which attached to those already fitted to make a full switch which switched over video, sound and signal valve heaters. That extra bit of switch is not there on my set and the signal and heater connections are hardwired to 625. I can only conclude that this set was had the 625 kit added after all stations were available on 625 and so the switch was dispensed with. Unless somebody has got that switch on a scrap chassis, I am very unlikely to be able to get one or improvise one so my plan is to use relays to do the necessary switching. While I am at it, I will do the Murphy modification which keeps all valve heaters running and thereby avoids the warn up delay switching between 405 and 625.

17th Dec 2019, 3:21 pm	#27
Niechcial,Steve Hexode Join Date: Jan 2007 Location: Beckenham, London, UK. Posts: 373	Re: Murphy V659/759 restoration I've now had time to go back to this set. The LOPT is away with Mike Barker for rewind, but there is plenty I can do in the meantime. I've put new aquadag on the tube and set it aside for the present. Having the tube out makes the whole chassis much more accessible. I've started to investigate the issues around this set seemingly being hard wired for 625 only. When it left the factory as a convertible set it was fitted with a partial systems switch which switched the timebase functions only. The converter kit then came with another few switch wafers which attached to those already fitted to make a full switch which switched over video, sound and signal valve heaters. That extra bit of switch is not there on my set and the signal and heater connections are hardwired to 625. I can only conclude that this set was had the 625 kit added after all stations were available on 625 and so the switch was dispensed with. Unless somebody has got that switch on a scrap chassis, I am very unlikely to be able to get one or improvise one so my plan is to use relays to do the necessary switching. While I am at it, I will do the Murphy modification which keeps all valve heaters running and thereby avoids the warn up delay switching between 405 and 625.