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Old 26th Aug 2017, 9:52 pm   #36
matspar
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Join Date: Aug 2009
Location: Portsmouth, Hampshire, UK.
Posts: 230
Default Re: And the next one! a GEC BT2147

I only managed an hour on the old girl today, had too many interruptions. Not getting anywhere fast at the moment. I can't seem to correct the frame collapse. I've replaced all the dodgy looking caps nearby, been through most of the resistors. The height slider pot is ok, has volts either side of the control. The scan coils and frame oscillator tx all have continuity. I was stopped in my tracks by crackling and a plume of smoke from R73 (V15 cathode decoupler?) which collapsed the eht and blew one of the mains fuses. Looks like a short which I can't trace. With R73 disconnected I'm back where I was with the frame collapse. The other thing which doesn't seem right is the HT rectifier. I've fitted a 1N4007 diode but it won't let me fit a series resistor. I've tried a few between 100 and 300R but they just burn up on switch on. Can anyone advise what sort of wattage resistor do I need? I've only ever done this on record players before (successfully)
In all not a great session today but I'm not giving up yet!
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