A Quick Viking 2 Question

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Tim WA1HnyLR:
Hi Ellen, I generally use 100 mfd 450 volt caps. The power supplies are solid stated . The LV supply comes up to 370V under load. It is advisable to use the LV supply for the screen voltage source for the modulator and eliminate the 20 bleeder resistor with the tap. This is a very poor means of supplying screen voltage. I take the screen voltage through a set of relay contacts as part of the  PTT system. 370 volts is a bit too high. I change the LV supply to choke inpoot . This lowers the supply voltage to about 260 volts. I clamped the bias at -24v with a string of shadio rack zeners . Aside from other audio mods such as changing the second 6AU6 to a triode connected 6AQ5 etc. Usually the filter cap used for the biass supply goes away . This should also be replaced with 100 mfd units @ 150VDC. Good luck, Tim WA1HnyLR

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