05-07-2016, 07:27 PM
Ok, so I have 2 remaining problems
I can't peak the RF section. I've checked:
- The wiring, and my repairs - nothing obvious there
- The mica caps in and around that area - all within co-ee of their expected values
- The tuning cap - no shorts in the RF (or other) plates
- The RF primary and secondary windings - no opens and the resistances are near enough to the circuit diagram
I have what seems common when the RF section won't peak - screwing the trimmer down tight causes the rf to roll off, but unscrewing it about 3/4 of a turn causes it to rise to a high point where it stays right until the screw is fully off. Schematic is below, middle section is the RF. Nostalgia air version here: http://www.nostalgiaair.org/Resources/do...013903.pdf
[Image: http://i241.photobucket.com/albums/ff222...y5xels.png]
And just the front end to try and make it a little clearer to read
[Image: http://i241.photobucket.com/albums/ff222...ahxhrc.png]
I'd really appreciate any ideas or comments on the problem because I think I've been staring at it too long, and I can no longer see any wood in the trees at all.
The second problem I can probably fix with a little perseverance. The vane assy in the shadow meter flicks around to one of the stops when the signal is not present, which completely blanks the display. I believe because its had wax in it, no matter how much I clean it there seems to be enough residual wax to 'stick' it to the stop, and not enough magnetism to pull it off again. So short of giving it a belt ever time I want to use it it's totally useless as-is. I've given it a fairly thorough cleaning with cotton buds and my fingernail to scrape it - anyone have any chemical or other ideas for removing the wax permanently and completely? Here is the wax problem after a bit of cleaning... I've had it completely apart and thought I'd got it all... but no.
I can't peak the RF section. I've checked:
- The wiring, and my repairs - nothing obvious there
- The mica caps in and around that area - all within co-ee of their expected values
- The tuning cap - no shorts in the RF (or other) plates
- The RF primary and secondary windings - no opens and the resistances are near enough to the circuit diagram
I have what seems common when the RF section won't peak - screwing the trimmer down tight causes the rf to roll off, but unscrewing it about 3/4 of a turn causes it to rise to a high point where it stays right until the screw is fully off. Schematic is below, middle section is the RF. Nostalgia air version here: http://www.nostalgiaair.org/Resources/do...013903.pdf
[Image: http://i241.photobucket.com/albums/ff222...y5xels.png]
And just the front end to try and make it a little clearer to read
[Image: http://i241.photobucket.com/albums/ff222...ahxhrc.png]
I'd really appreciate any ideas or comments on the problem because I think I've been staring at it too long, and I can no longer see any wood in the trees at all.
The second problem I can probably fix with a little perseverance. The vane assy in the shadow meter flicks around to one of the stops when the signal is not present, which completely blanks the display. I believe because its had wax in it, no matter how much I clean it there seems to be enough residual wax to 'stick' it to the stop, and not enough magnetism to pull it off again. So short of giving it a belt ever time I want to use it it's totally useless as-is. I've given it a fairly thorough cleaning with cotton buds and my fingernail to scrape it - anyone have any chemical or other ideas for removing the wax permanently and completely? Here is the wax problem after a bit of cleaning... I've had it completely apart and thought I'd got it all... but no.
There are no personal problems that can't be overcome with the liberal application of high explosives
