[Kurt P]

Hi, I made some progress on an 89B Code 123 about a year and a half ago, other things got in the way and I had to shelf this project for a while.  I got as far as finding a new speaker, reworking the power supply, full recap and replacing resistors.  I have worked on a bunch of AA5 radios, this is my first 30s Philco...

I rewound the oscillator coil which I thought would be the final task, put it in place and fired it up... only to get a constant 800hz to 1khz tone depending on how I tune the variable cap.  I think this sound was there when I tested the radio after doing everything but the oscillator coil, so I'm not sure the oscillator coil is causing the issue.  This is when I ran out of time for this project.

However, looking at this chassis now, I'm not sure I wound the coil correctly at all.  If I'm reading the schematic correctly and testing the correct leads on the coil, the primary is open.  However, I'm not sure I'm checking this correctly.  It's part 7 in the service bulletin 146B.

Does anyone have some troubleshooting tips to 1) check if I've rewound the coil correctly or made a mess of it, and 2) help to track down the source of the oscillation?  Several of the screen grids are tied together which makes it difficult to pinpoint where the oscillation is coming from.

On a positive note I did go back and double check all the work I did and found that I had used a 5K resistor where the schematic called for a 50K.  So that's something!

Thanks,

Kurt.