30-12-2016, 02:46 PM
Crackle, my earlier posts show R12 was tested with the result there was no HT voltage. Continuity showed a connection to ECH81 anode as it should be one side. The other side of R12 shows no supply to HT. Not even when pushing the knobs. I assumed a break in the switch but underestimated the gaining of access. Now I discovered a useful diagram you can see on Radio Museum. The Telefunken ECH81 is shown with R12 at 33K only between HT and Triode anode. The anode should pass 13 milliamps (in ref book) and voltage around 100 DC. Not sure about the black circles with digits but at a quick glance maybe current? The two smoothing condensers also show two paths - one centre tapped if I recall.
Yes, I am not going to dismantle the board. Refugees suggestion was solid enough. I can try and trace the board from the tracks and, yes, WD40 is worth a go.
Yes, I am not going to dismantle the board. Refugees suggestion was solid enough. I can try and trace the board from the tracks and, yes, WD40 is worth a go.
