Coronado dial calibration way off

[Kurt Draper]

Hi, I am Kurt. this is my first post here. I have a Coronado am/fm 7 tube radio model 46-RA 85762-A. The number on the chassis is 6A85 113145. I can’t find a schematic for it. I look in through Coronado, Airline, Belmont & Wells Gardner. Not sure who manufactured it, but the manner the numbers are stamped on the back of the chassis are the same as other Wells Gardner Airlines in my collection. I recapped it replaced some resistors and cleaned the controls. It is excellent on am, decent on fm but the dial pointer is way off. Local station 96.9 comes in on 95 & 840 am comes in at 910. The only trimmers I see are on the tuning capacitor. Adjusting them makes the signal louder or weaker but the stations don’t move. Moving the pointer isn’t an option because there off in opposite directions. Any help on how to get it closer is greatly appreciated. Thanks Kurt

[Michael Terrell]

On Sunday, February 23, 2020 at 4:57:17 PM UTC-5, Kurt Draper wrote:
> Hi, I am Kurt. this is my first post here. I have a Coronado am/fm 7 tube radio model 46-RA 85762-A. The number on the chassis is 6A85 113145. I can’t find a schematic for it. I look in through Coronado, Airline, Belmont & Wells Gardner. Not sure who manufactured it, but the manner the numbers are stamped on the back of the chassis are the same as other Wells Gardner Airlines in my collection. I recapped it replaced some resistors and cleaned the controls. It is excellent on am, decent on fm but the dial pointer is way off. Local station 96.9 comes in on 95 & 840 am comes in at 910. The only trimmers I see are on the tuning capacitor. Adjusting them makes the signal louder or weaker but the stations don’t move. Moving the pointer isn’t an option because there off in opposite directions. Any help on how to get it closer is greatly appreciated. Thanks Kurt

Is the Local Oscillator coil damaged, or covered in bad wax that has adsorbed a lot of moisture?

[George Gonzalez]

That's often due to dustr or grease on the tuning capacitor plates. Radios that were in the kitchen often got really greasy inside. Turned on during making breakfast, and they were virtual convection fans dragging in bacon grease. You might try a generous amount of Brake Parts Cleaner on the tuning cap.

That certainly applies to the AM band problem, but the FM issue seems to be the opposite-- maybe the FM oscillator coil needs to be squeezed a bit tighter?? Dunno. These things are often mysteries. Longago I had a BC-221 frequency meter, WW2 vintage. The main coil had somehow, inexplicably, lost some inductance. This is a silver-plated wire tightly wound on a toothed ceramic form, so thr coil moving sounds unlikely. I ended up having to place a very small ferrite tuning slug in the middle of the coil to get the frequency readings to match the codebook. BTW does anyone know that Philco made a digital frequency counter in 1940 just to automatically print these codebooks, one for each BC-221?? ? Amazing.