Re: KW2000 Transceiver
Just an update on the KW. I removed the VFO box, replaced two black Hunts that had just about disintegrated, checked the resistors and mechanical stability of the coil and associated capacitors. Also I have replaced the ECF82 with a PCF802 which was designed of course for tv line oscillators, and has a much more stable construction. I simply replaced the LM7805 with a LM7808 in the heater supply mod. to provide 9 volts the PCF802 needs. (I have a BC212 in the earth leg of the LM7808 to gain a volt] The Xtal oscillator valve is running from the existing 12 volt heater rail via a 20 ohm resistor. The transceiver now settles down much quicker and no noticeable drift after 30 minutes.
I think I will not be adding a huff puff stabiliser, as I am more than happy with it as it is now. Thank you for all your interest and help.
David
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