Quad II question: High B+ a problem?
Right now the wall outlet shows 235.5 vac, but in the evening it can reach at least 237 vac. The Quad Im measuring now is set to 240v, and the HT winding is producing 312-0-312vac. 5v heater is 5.0v and 6.3v is 6.5v (with RCA 6L6GC, 0,9A heaters). At the first (33uF) cap I now have exactly 380v, and at the screen supply (at the 47uF cap) there is +375v. Plate voltage 370-372 and shared cathode R sits at 27,5v with these tubes. Rectifier is Philips Miniwatt GZ34.
Using the KT66 makes the bias voltage go up and the 6.3v go down a bit, since these tubes draw a bit different currents. But the HT stays around the same high value.
I did an experiment: connected a 4W 100 ohm wirewound in series with the 5AR4. Presto, 340v B+ like in the original schematics! But the R got _very_ hot and where does one put it (since I dont want to drill the chassis)....
Any ideas?
Martin
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