07-26-2009, 02:07 PM
Codefox, I'm keeping the same capacitance the sets were designed for, I just wondered if my 400v caps that were at their upper voltage limit. I don't have an issue with the slightly higher price of the 630volt caps, I just happened to get some 400v units at the time. I'm trying to stay away from electrolytics whenever possible when I rebuild a unit, that's why I'm using plastic caps whenever possible. FWIW, I found 600v plastic caps at AES. B+ shouldn't be an issue after replacing the filter with the same capacitance.
Music, my 20 lists a primary of 105-125volts. However at 125 the secondaries will put out a higher voltage than the tube filaments and plates were designed for. Recent threads on ARF discussed using a bucking transformer or a resistor in series with the primary. The obvious issues are finding space for a transformer or adequate area for heatsinking a wirewound resistor. I have a Japanese superhet with a 100v primary I run off a variac as I haven't gotten around to reducing the input voltage permanently.
Dave
Music, my 20 lists a primary of 105-125volts. However at 125 the secondaries will put out a higher voltage than the tube filaments and plates were designed for. Recent threads on ARF discussed using a bucking transformer or a resistor in series with the primary. The obvious issues are finding space for a transformer or adequate area for heatsinking a wirewound resistor. I have a Japanese superhet with a 100v primary I run off a variac as I haven't gotten around to reducing the input voltage permanently.
Dave
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