04-28-2020, 02:34 PM
Bob
Thanks for your help. It got me in the ball park once I could drive a signal from the Oscillator grid.
What I found was there are 2 caps marked c35 on the schematics !! Put two in on opposite sides of the chassis making the value x2. And one missing cap needed for isolation. Gotta love Philco schematics…My Bad!
Once corrected I was able to get back to the correct values for the oscillator RC timing values
Everything trim’d up but couldn’t get through the rf amp
Antenna coil measured crazy on the secondary. I unwound it and it
turned out to be not even close to the schematic. Ended up unwinding and documenting it then rewind
There were 3 layers separated by parchment paper. I rewound it. What a pain! Wish I took your advice and left it alone.
Final problem was some sort of resistance wire buried deep in the chassis inside of a covering....(R8).
R8 was open so no bias on the cathode of the rf amp. I attached pictures of the coil and the (resistance wire R8)
Radio is working and trimmed to spec.
Will never go near one of these again!
Another Philco from H**l
Tom
Thanks for your help. It got me in the ball park once I could drive a signal from the Oscillator grid.
What I found was there are 2 caps marked c35 on the schematics !! Put two in on opposite sides of the chassis making the value x2. And one missing cap needed for isolation. Gotta love Philco schematics…My Bad!
Once corrected I was able to get back to the correct values for the oscillator RC timing values
Everything trim’d up but couldn’t get through the rf amp
Antenna coil measured crazy on the secondary. I unwound it and it
turned out to be not even close to the schematic. Ended up unwinding and documenting it then rewind
There were 3 layers separated by parchment paper. I rewound it. What a pain! Wish I took your advice and left it alone.
Final problem was some sort of resistance wire buried deep in the chassis inside of a covering....(R8).
R8 was open so no bias on the cathode of the rf amp. I attached pictures of the coil and the (resistance wire R8)
Radio is working and trimmed to spec.
Will never go near one of these again!
Another Philco from H**l
Tom