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Neil Purling · 21st Sep 2011, 7:42 am

If it is totally dead, no heaters I assume you changed C19 (across the mains) for a X2 type. I also assume the mains switch is not playing up.
Are the replacement electrolytic capacitors OK. Check them on the voltage range of your meter first. If they are fine then they may still hold a charge.
See if there is a short to chassis from either side of the resistor between both capacitors.
if one has gone 'bang' it may be obviously swollen or the end is blown outwards.
If the set was drawing excessive HT the flash may have been the rectifier protesting.
I hope it survived.
Remove all the valves and check the auto-transformer. I would hope there is continuity all along that.
With the limiter in risk a quick on-off, with a meter across the heater chain.
It should give a reading close to what you'd expect and something like 8 volts without the limiter when off-load.
If all is well check by putting any valve in apart from the rectifier and if should glow normally.
I wouldn't expect a LT fault. It really sounds as if the set was drawing excessive HT and the rectifier experienced a flash-over. Let us know what you find.

21st Sep 2011, 7:42 am	#16
Neil Purling Nonode Join Date: Jul 2005 Location: Hull, East Yorkshire, UK. Posts: 2,087	Re: KB FB10 "Toaster" If it is totally dead, no heaters I assume you changed C19 (across the mains) for a X2 type. I also assume the mains switch is not playing up. Are the replacement electrolytic capacitors OK. Check them on the voltage range of your meter first. If they are fine then they may still hold a charge. See if there is a short to chassis from either side of the resistor between both capacitors. if one has gone 'bang' it may be obviously swollen or the end is blown outwards. If the set was drawing excessive HT the flash may have been the rectifier protesting. I hope it survived. Remove all the valves and check the auto-transformer. I would hope there is continuity all along that. With the limiter in risk a quick on-off, with a meter across the heater chain. It should give a reading close to what you'd expect and something like 8 volts without the limiter when off-load. If all is well check by putting any valve in apart from the rectifier and if should glow normally. I wouldn't expect a LT fault. It really sounds as if the set was drawing excessive HT and the rectifier experienced a flash-over. Let us know what you find.