12-30-2017, 07:49 PM
Thanks for that info, Arran.
I have noticed that the Fisher K-Trans were made by Automatic. I have a replacement Miller ratio detector transformer, and on the plastic base...it, too, has "Automatic Mfg. Co." molded in the plastic.
So I wonder if Automatic Mfg. Co. actually made all of these, then sold them to manufacturers such as Fisher, and resellers such as Miller?
I remembered that the limiter coil (3rd IF) had a mica "sandwich" that looked very clean through the plastic. So...I opened it back up again and found that one end of the coil was broken at the terminal. I removed one turn, resoldered, and bingo...continuity again.
I reinstalled the coil, touched up its alignment by ear (on that coil only) and FM then performed better (louder...and I can hear the interstation noise now where I could not previously). But it is still not up to par.
After rebuilding all of the electrolytic cans and replacing the selenium bridge rectifier in the preamp filament circuit with individual 1N4007 diodes, I tried it out again today only to notice that the FM tuning eye is responding in the reverse of how it should be responding. When I tune in an FM station, instead of the "eye" narrowing as it should, it is actually widening.
I have noticed that the Fisher K-Trans were made by Automatic. I have a replacement Miller ratio detector transformer, and on the plastic base...it, too, has "Automatic Mfg. Co." molded in the plastic.
So I wonder if Automatic Mfg. Co. actually made all of these, then sold them to manufacturers such as Fisher, and resellers such as Miller?
I remembered that the limiter coil (3rd IF) had a mica "sandwich" that looked very clean through the plastic. So...I opened it back up again and found that one end of the coil was broken at the terminal. I removed one turn, resoldered, and bingo...continuity again.
I reinstalled the coil, touched up its alignment by ear (on that coil only) and FM then performed better (louder...and I can hear the interstation noise now where I could not previously). But it is still not up to par.
After rebuilding all of the electrolytic cans and replacing the selenium bridge rectifier in the preamp filament circuit with individual 1N4007 diodes, I tried it out again today only to notice that the FM tuning eye is responding in the reverse of how it should be responding. When I tune in an FM station, instead of the "eye" narrowing as it should, it is actually widening.
--
Ron Ramirez
Ferdinand IN
