12-11-2021, 04:41 PM
I went through the alignment again, verifying the signal generator frequency with a digital radio at each step. Basically same result, dial is 40kc low at 950, and 25kc low at 760. Couldn’t verify any stations high up on dial, as reception wasn’t good and stations I did pick up didn’t state call sign.
I verified that the oscillator was tracking correctly at 600kc, but found it was 50kc high at 1200 dial setting. I found oscillator at 1670kc when dial at 1150 (so oscillator at 520kc).
Would have to be a condenser issue I would think; this radio has Magnetic Tuning (AFC), but acts the same with it on or off, and I did verify that switch does short the AFC out, as does dial switch.
At least I know where to start looking. I did notice that the mixer 6A8 was microphonic...wish I had some others to try, as oscillator is same type.
I verified that the oscillator was tracking correctly at 600kc, but found it was 50kc high at 1200 dial setting. I found oscillator at 1670kc when dial at 1150 (so oscillator at 520kc).
Would have to be a condenser issue I would think; this radio has Magnetic Tuning (AFC), but acts the same with it on or off, and I did verify that switch does short the AFC out, as does dial switch.
At least I know where to start looking. I did notice that the mixer 6A8 was microphonic...wish I had some others to try, as oscillator is same type.
