11-20-2021, 11:59 PM
Just for fun, I decided to try and see if I could convert a 54C to use octal tubes in order to eliminate the two large dropping resistors. It was mostly successful.
Mostly?
Well, now the thing will not tune correctly. The oscillator is working, but is way, way out of range - beyond a simple alignment issue.
Our local AM station at 990 kc won't even come in. Stations which should be on the higher end of the band are coming in on the lower end.
IFs are properly aligned at 460 kc.
Please look over the modified schematic below, and then tell me -
Would you consider this to be an oscillator coil issue? Or is there something else I am missing here?
Thanks. Oh, and you can compare the schematic below with the original 54 schematic which may be found here.
Mostly?
Well, now the thing will not tune correctly. The oscillator is working, but is way, way out of range - beyond a simple alignment issue.
Our local AM station at 990 kc won't even come in. Stations which should be on the higher end of the band are coming in on the lower end.
IFs are properly aligned at 460 kc.
Please look over the modified schematic below, and then tell me -
Would you consider this to be an oscillator coil issue? Or is there something else I am missing here?
Thanks. Oh, and you can compare the schematic below with the original 54 schematic which may be found here.
--
Ron Ramirez
Ferdinand IN
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