02-13-2006, 06:42 PM
Here's the latest update...
I have checked through almost all tha capacitors, and all are good.(The only ones I haven't checked are inaccessible withough pulling the RF subchassis again- a last ditch maneuver) I even checked the rebuilt bakelites. (The micas and the one picaf. rated bakelite were too small value to check...) Also, all the resistors, except for the one which was dead wrong, are correct. The dead wrong one has been replaced temporarily with a composite totaling proper ohmage.
I replaced the test volume control with the original, and it seems to be dead, no real volume increase or decrease, and would absolutely not test for continuity. It is supposed to be 2 meg total, with a tap at 1 meg ohm. The test unit is a 1 meg, with tap, and it actually ohms out at 750k ohms total, so I think replacement is in order in any case. Where can I get a proper volume control? Also, is it possible the dead wrong resistor blew out the volume control? Cooked it perhaps?
I think my two problems are:
1. Volume control shot- I think the amp section is otherwise fine. With the test VC in place, it does increase/decrease volume.
2. Totally out of correct alignment. I think I whacked everything out of kilter trying to adjust away the resistor isue before I found it. Hey- this is my first project set, so I'm allowed... lol
I still have to figure out the problems causing the motorboating on certain freq's, and the squeal on others. I think it is all related to the VC and alignment. Everything else checks out.
Anybody in South Jersey/ Philadelphia area wanna stop by and play with this radio?
Scott
I have checked through almost all tha capacitors, and all are good.(The only ones I haven't checked are inaccessible withough pulling the RF subchassis again- a last ditch maneuver) I even checked the rebuilt bakelites. (The micas and the one picaf. rated bakelite were too small value to check...) Also, all the resistors, except for the one which was dead wrong, are correct. The dead wrong one has been replaced temporarily with a composite totaling proper ohmage.
I replaced the test volume control with the original, and it seems to be dead, no real volume increase or decrease, and would absolutely not test for continuity. It is supposed to be 2 meg total, with a tap at 1 meg ohm. The test unit is a 1 meg, with tap, and it actually ohms out at 750k ohms total, so I think replacement is in order in any case. Where can I get a proper volume control? Also, is it possible the dead wrong resistor blew out the volume control? Cooked it perhaps?
I think my two problems are:
1. Volume control shot- I think the amp section is otherwise fine. With the test VC in place, it does increase/decrease volume.
2. Totally out of correct alignment. I think I whacked everything out of kilter trying to adjust away the resistor isue before I found it. Hey- this is my first project set, so I'm allowed... lol
I still have to figure out the problems causing the motorboating on certain freq's, and the squeal on others. I think it is all related to the VC and alignment. Everything else checks out.
Anybody in South Jersey/ Philadelphia area wanna stop by and play with this radio?
Scott
Old Cars, Old Radios, Old Pipes and Young Women... What more is there?
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