04-13-2023, 06:49 PM
Hi Murf,
Touch the grid cap on the 6K7 rf amp and hear if that quenches the motor boating. I suspect it will. Check the ant side of the band switch for cleanliness and good connection. The value of the cathode resistor in the rf amp stage. If too low that can be the issue. Too high it will just work lousy. If you have a spare 6K7 give that a try. See if pin 1 on the socket (6K7) is grounded. It maybe used as a tie point for other things, they don't show on the pictorial. If there isn't any other connection go ahead and ground it. Align the rf stage w/a generator. As a last resort try adding .047 630v cap from pin 4 (screen grid) to ground.
https://worldradiohistory.com/Archive-Ri...37-GHI.pdf
Go to pg 197
Touch the grid cap on the 6K7 rf amp and hear if that quenches the motor boating. I suspect it will. Check the ant side of the band switch for cleanliness and good connection. The value of the cathode resistor in the rf amp stage. If too low that can be the issue. Too high it will just work lousy. If you have a spare 6K7 give that a try. See if pin 1 on the socket (6K7) is grounded. It maybe used as a tie point for other things, they don't show on the pictorial. If there isn't any other connection go ahead and ground it. Align the rf stage w/a generator. As a last resort try adding .047 630v cap from pin 4 (screen grid) to ground.
https://worldradiohistory.com/Archive-Ri...37-GHI.pdf
Go to pg 197
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!
Terry