Re: R1155 Modern Power Supply
To help you in your search for a power unit, the requirements are:
1. LT for valve heaters: 6V DC or AC (6.3V AC is OK) at 4 amps. The current requirement can be reduced if the direction finding valves are no longer fitted, and its common to find sets with those valves missing.
2. HT: 210V DC at about 75mA - though the manuals state 110mA. I think the lower figure is again for sets with the DF valves missing, and is what I have measured in practice. Incidentally the 210V is not particularly critical, you can get way with about 20V either way - up or down from a nominal 210V.
3. The HT- needs to be isolated from ground or the chassis of the power supply. This is not a common requirement in typical supplies that are "general purpose", so you need to watch for this. This is because the HT- rail is actually at about -30V relative to the set chassis for biasing purposes.
And I would reiterate ex_seismic's comments about your set. If not restored, apply power with the utmost care! Preferably check for that perished rubber wiring before you put power on it. And even if you are lucky enough to have cotton covered wiring, there may well be leaky capacitors, etc, which will draw far too much HT current. Be prepared to switch off quickly and watch for smoke!
Richard
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