UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - Suspect Mains Transformer in 1930s Radio P.S.U.

'LIVEWIRE?' · 20th Apr 2018, 11:45 am

I'm beginning to suspect the 1821. With only the rectifier valve plugged, I'm getting ca. 240-0-24oVAC across the HT Secondary, and just over 4v on the heater winding. The heater has continuity, but there is no DC o/p. The valve doesn't warm up, even if left powered for a few minutes, so no voltage is dropped via the limiter. I'm reluctant to plug in the incorrect rectifier valve (a VU39) which was in the set when I received it, as the Ih of the 39 is 4Amps, rather than the 1Amp the 1821 draws. Not good for the transformer!

20th Apr 2018, 11:45 am	#52
'LIVEWIRE?' Rest in Peace Join Date: Mar 2006 Location: N.W. Oxfordshire(Chipping Norton) Posts: 7,306	Re: Suspect Mains Transformer in 1930s Radio P.S.U. I'm beginning to suspect the 1821. With only the rectifier valve plugged, I'm getting ca. 240-0-24oVAC across the HT Secondary, and just over 4v on the heater winding. The heater has continuity, but there is no DC o/p. The valve doesn't warm up, even if left powered for a few minutes, so no voltage is dropped via the limiter. I'm reluctant to plug in the incorrect rectifier valve (a VU39) which was in the set when I received it, as the Ih of the 39 is 4Amps, rather than the 1Amp the 1821 draws. Not good for the transformer!