11-16-2008, 10:01 PM
Going from memory but here goes.
The IF frequency is 9.1 mHz and the FM1000 detector oscillator nominal frequency is the same. I believe that the procedure has you align the IF using a signal generator set at 9.1 mHz then align the detector. If your radio is receiving stations then your IF must be set high at 10.4 mHz. The detector will demodulate the signal however distorted when maladjusted. The cap should change the frequency of the oscillator. It is very 'touchy' though. When adjusted properly the sound is comparable to any ratio detector or discriminator. Try getting the IF aligned to the correct frequency then the detector may work as designed. The cap may be at the limit of adjustment.
My first 48-482 ( I have restored three.) had a broken core in the FM1000 transformer. I removed the transformer and replaced the core with one from a TV IF. I had no trouble aligning the detector after reassembling the transformer.
All paper caps in the set should be replaced. In all three radios there were many leaky caps. Care should be taken to place the new caps and leads as near as possible to the original locations. Stray coupling can cause many and sundry problems that are very difficult to find.
I assume that you have read my posts on 'the other forum' re other pitfalls so will not repeat here.
The IF frequency is 9.1 mHz and the FM1000 detector oscillator nominal frequency is the same. I believe that the procedure has you align the IF using a signal generator set at 9.1 mHz then align the detector. If your radio is receiving stations then your IF must be set high at 10.4 mHz. The detector will demodulate the signal however distorted when maladjusted. The cap should change the frequency of the oscillator. It is very 'touchy' though. When adjusted properly the sound is comparable to any ratio detector or discriminator. Try getting the IF aligned to the correct frequency then the detector may work as designed. The cap may be at the limit of adjustment.
My first 48-482 ( I have restored three.) had a broken core in the FM1000 transformer. I removed the transformer and replaced the core with one from a TV IF. I had no trouble aligning the detector after reassembling the transformer.
All paper caps in the set should be replaced. In all three radios there were many leaky caps. Care should be taken to place the new caps and leads as near as possible to the original locations. Stray coupling can cause many and sundry problems that are very difficult to find.
I assume that you have read my posts on 'the other forum' re other pitfalls so will not repeat here.
Kind regards,
Terry
http://home.comcast.net/~suptjud/
"Life is simpler when you plow around the stump."
