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PJL · 30th Jul 2018, 10:53 am

Chris is correct, a bridge rectifier would result in an AC voltage with respect to earth on the chassis.

I would still recommend an external 240-120V isolating transformer and put a US style plug on the set.

I have rewired US sets by half wave rectifying the heater circuit and rewiring the field coil in series to drop the HT voltage:
1. Put a 100 ohm resistor between the mains and the 1D6 anode.
2. Rewire the field coil in place of the choke
3. Put a 1N4007 in series with the heater chain.

A single capacitor dropper is not going to be a good idea on this set as the HT current includes the field coil current and will be >100 mA.

30th Jul 2018, 10:53 am	#3
PJL Dekatron Join Date: Sep 2005 Location: Seaford, East Sussex, UK. Posts: 5,997	Re: Cap. dropper + full wave bridged set Chris is correct, a bridge rectifier would result in an AC voltage with respect to earth on the chassis. I would still recommend an external 240-120V isolating transformer and put a US style plug on the set. I have rewired US sets by half wave rectifying the heater circuit and rewiring the field coil in series to drop the HT voltage: 1. Put a 100 ohm resistor between the mains and the 1D6 anode. 2. Rewire the field coil in place of the choke 3. Put a 1N4007 in series with the heater chain. A single capacitor dropper is not going to be a good idea on this set as the HT current includes the field coil current and will be >100 mA. Last edited by PJL; 30th Jul 2018 at 11:05 am.