11-23-2015, 02:15 AM
Got my 116B a couple days ago. What fun scrounging all the necessary tubes.
1) Are 6D6's actually a decent sub for 78's? This has had all the 78's replaced with 6D6's.
2) I have no LO on the AMBCB. If I inject the appropriate frequency, it will pass stations through. Interestingly, ALL other bands work pretty well, including LW. Given that all the LO coils look to be in series on this radio, I'm having difficulty understanding how all the other bands can work, but not AMBCB.
3) I'm fighting a problem with the AGC/detector. There's virtually no AGC action at all, even though I've already replaced practically every component in the detector/AGC circuit. If I apply a bias voltage to the AGC bus, it does change the stage gain, but the detector output remains distorted. The voltages on most points are good.
1) Are 6D6's actually a decent sub for 78's? This has had all the 78's replaced with 6D6's.
2) I have no LO on the AMBCB. If I inject the appropriate frequency, it will pass stations through. Interestingly, ALL other bands work pretty well, including LW. Given that all the LO coils look to be in series on this radio, I'm having difficulty understanding how all the other bands can work, but not AMBCB.
3) I'm fighting a problem with the AGC/detector. There's virtually no AGC action at all, even though I've already replaced practically every component in the detector/AGC circuit. If I apply a bias voltage to the AGC bus, it does change the stage gain, but the detector output remains distorted. The voltages on most points are good.
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