scott fm converter alignment/adjustment

[Bill Anderson]

Hello,

has anyone here done an alignment / adjustment on one of the scott philharmonic fm converters? there are oscillator and antenna trimmers for all 3 ranges but cannot locate any adj procedure for it.... I attached the one I have and tuned it to one of the local fm stations here...the sound output is very distorted, touching any of the  trimmers in that range either kills the signal all together or makes the output worse...I was thinking it probably needs an alignment done.

thanks again, and hopefully once the speaker is back from the re-coning service, I will be good to go, everything else has checked out ok

[Norman S Braithwaite]

Any adjustments on the FM converter will be RF or oscillator adjustments that will affect signal strength and frequency but should not affect audio sound quality.  Have you aligned the FM IF and discriminator circuits in the Philharmonic tuner?

Norman

[Bill Anderson]

Hi Norman,

Thanks for responding. I have not myself. The set was electrically restored before I purchased it, but I was thinking the same thing. I was told that all the bands were functioning properly, so far the fm band is the only one I have seen with issues..the audio is what I describe as "scratchy",  volume is there but very distorted. I was going to attach a signal generator to the ant terms of the philly chassis without the converter and see if the same problem appears.

[Bill Liers]

Bill

There's a .pdf for the converter on Nostalgia Air. There is a section describing alignment on the last page. I have found that the trimmers can stick and break or short from sitting for years and some may need replacement. Values are in the doc too.

The discriminator alignment is sensitive and goes off easily if you jar the chassis. You may have to go over it a few times to make it sound right. I also find that many of the tubes in the FM chain are weak and should be replaced. Good news is that the set sounds great when you get it properly aligned.

good luck, Bill

[Bill Anderson]

Thanks Bill,

Thank you for that link, that is the info I was looking for...The set was recently electrically restored, but the chassis was shipped, so, it looks like an alignment check is in order. I was told all of the tubes are fresh, and the restorer did label each with the readings found using a Hickock 539xx.

I have a full set of Rider's but have not been unpacked since I have not got my work room up and running, I thought I remembered seeing that information in there....I was hoping since the set was restored it was going to be a "plug n play", but I can't remember when that has ever happened with an antique radio purchase, regardless of the price...lol

thanks again