No AM/FM from Fisher Ambassador V console

[nickdinatale]

Finally getting around to paying some attention to the console that has been sitting in my kitchen for a month or two. Replaced the couple of electrolytics in the tuner today to no avail. The stereo beam tube lights up, but no blue bars, and no reception at all when switched to any AM/FM inputs (not even crackling). Any thoughts where I should be looking? Thanks!

Link to schematic: http://www.fisherconsoles.com/service manuals/ambassador v a68 sm.pdf

 

[dcgillespie]

I'd check if there is the proper voltage appearing at the output of R28 and R35 in the power supply. It sounds like there is no B+ voltage going to the tuner circuits, and that would certainly cause the problems you are noting. If one of those resistors is open, I'd check the can cap they are associated with. It may have gone south and taken one of the resistors with it.

Good luck with it!

Dave

 

[gadget73]

Also worth reseating the tubes if you have not, and verifying the tubes are all present, in the right hole, and good.

 

[nickdinatale]

I'd check if there is the proper voltage appearing at the output of R28 and R35 in the power supply. It sounds like there is no B+ voltage going to the tuner circuits, and that would certainly cause the problems you are noting. If one of those resistors is open, I'd check the can cap they are associated with. It may have gone south and taken one of the resistors with it.

Good luck with it!

Dave

Thanks for this, Dave. Turns out I had overlooked R28, which was pretty burnt. Also bypassed the can caps with new caps underneath, and the tuner section is alive & well again.