09-27-2013, 08:05 AM
Well, I did find more "modifications". For instance, a .01 cap between the screen grid and control grid of the mixer tube that obviously didn't belong there (it was a 'newer' cap with long leads just wrapped around other components on either end). Removing that stopped the parasitic oscillations. Gain is great on all bands, but I still can't get any adjustment on the high end of Band 1 for the antenna. Seems closer, though, since I spread the plates on the end section of the antenna tuner.
Also recapped the set completely. That didn't really change much, other than the AGC works a bit better. And I lost one thing: The BFO no longer oscillates. That's driving me crazy, too. It's a simple Hartley oscillator. Everything seems good, voltages OK, coil is good, caps are good. Circuit is correct.. even put in a new 1U5, but still nothing. This is most odd since it was working before I started. :/
Also recapped the set completely. That didn't really change much, other than the AGC works a bit better. And I lost one thing: The BFO no longer oscillates. That's driving me crazy, too. It's a simple Hartley oscillator. Everything seems good, voltages OK, coil is good, caps are good. Circuit is correct.. even put in a new 1U5, but still nothing. This is most odd since it was working before I started. :/
