10-24-2021, 08:44 PM
Hi Texan George,
In theory (!!??!), tuning of the IF Stage should have an equal effect across the band, as the Convertor Stage converts all frequencies to the fixed IF frequency.
There could be one or more of several possible issues with the Convertor Stage. The most likely cause of reception at the high end of the band but loss of function as you tune down the band is shorting of the ganged variable tuning condenser. A click or static while the tuner is turned is a dead giveaway. Look carefully to ensure that the plates are not shorting. In addition, if the aluminum corrodes, there are almost thready bristles that will short the condenser out, almost like "SMD" An ohmmeter may be useful but you will have to unsolder the connections. I had this problem with a Crosley 02CA I restored for a friend (BTW, rubber wiring, not for the faint of heart). Take a set of feeler gauges and sweep the gaps between the plates, either open or closed will help. compressed air after this procedure helps.
If the Unit passed the 2nd radio "squeal test" then the Oscillator section of the tuning condenser is OK and the problem is with the RF section.
Hope this helps.
In theory (!!??!), tuning of the IF Stage should have an equal effect across the band, as the Convertor Stage converts all frequencies to the fixed IF frequency.
There could be one or more of several possible issues with the Convertor Stage. The most likely cause of reception at the high end of the band but loss of function as you tune down the band is shorting of the ganged variable tuning condenser. A click or static while the tuner is turned is a dead giveaway. Look carefully to ensure that the plates are not shorting. In addition, if the aluminum corrodes, there are almost thready bristles that will short the condenser out, almost like "SMD" An ohmmeter may be useful but you will have to unsolder the connections. I had this problem with a Crosley 02CA I restored for a friend (BTW, rubber wiring, not for the faint of heart). Take a set of feeler gauges and sweep the gaps between the plates, either open or closed will help. compressed air after this procedure helps.
If the Unit passed the 2nd radio "squeal test" then the Oscillator section of the tuning condenser is OK and the problem is with the RF section.
Hope this helps.
"Do Justly, love Mercy and walk humbly with your God"- Micah 6:8
Best Regards,
MrFixr55
