I had a similar problem when I first got my system (Haight era). At the time I was living within a mile of the hill with our city's radio and television broadcast antennas. I spoke to Serge, and the first thing he asked was if I was near any radio transmitters. He suggested a few modifications (shielding, capacitors across the power supply rails, etc.), but the only effective solution came when I moved.
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Re: VCO, NTO, PCO Instability,
2014-06-24 by jimdenault