14-07-2020, 02:08 PM
Hi.
Today's progress has been very encouraging. As the main smoother looked in a sorry state and there were issues with transformers I decided to do only cold checks on the set. I also set about re-stuffing all the bigger value wax caps, the small ones on cathode decoupling and heaters I decided to leave until the set was powered up. Yesterday I started to reform the smoothers one of which that was way past its best has been replaced so out came the bench PSU and a selection of series resistors. Yesterday the voltage gradually came up to 95v before shutting up the shed. This morning first thing all was powered up again and by mid day I saw 200v so it was time to externally feed the heaters. I was rewarded with a really good video waveform on the detector after replacing two EF50 valves, no sound though as another EF50 is faulty, confirmed by swapping one from the video op. The other encouraging thing is the line oscillator runs as does the frame, even the slider controls are operating fine.
Today's progress has been very encouraging. As the main smoother looked in a sorry state and there were issues with transformers I decided to do only cold checks on the set. I also set about re-stuffing all the bigger value wax caps, the small ones on cathode decoupling and heaters I decided to leave until the set was powered up. Yesterday I started to reform the smoothers one of which that was way past its best has been replaced so out came the bench PSU and a selection of series resistors. Yesterday the voltage gradually came up to 95v before shutting up the shed. This morning first thing all was powered up again and by mid day I saw 200v so it was time to externally feed the heaters. I was rewarded with a really good video waveform on the detector after replacing two EF50 valves, no sound though as another EF50 is faulty, confirmed by swapping one from the video op. The other encouraging thing is the line oscillator runs as does the frame, even the slider controls are operating fine.
