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Philco 48-482 Alignment
#1

Good Morning,
I've gone through the AM alignment with a breeze....and she works great...

"BUT"

That darn FM alignment has me and my 75 year old,  experienced friend baffled.  If you can help me with the first step I'd appreciate it....   The FM works but it's a bit garbled.....

Here's a pic of the first FM alignment instructions.....
   

  it says to make this device with a cap and resister...and place it where?  and this "Padder" from what I gather is just a trimmer cap in one of the if cans that's used for adjusting the Lower frequencies??
   

Thanks Much,
Mike
#2

After digging a bit I found this off of the Antique Radio site by Tom Albrecht....

https://antiqueradios.com/forums/viewtop...6&t=284598

So I'll attempt his method.....
Mike
#3
Lightbulb 

The alignment for the most part went well....

Seems that I read somewhere that if you tune in a weak station, it comes in loud, but along with all the loud noise as well.  Also during tuning, it's very noisy until you get right on the station and I think this is normal for FM during this era...  If I have good reception, I get a very good clear signal.....I had the FM antenna wire weaved in and out of the power cord (twisted cloth covered cord) but it didn't seem to help much.....until I unplugged the Philco from my Variac which is also an isolation transformer and plugged it directly into the house outlet....a very nice improvement...

A little more fooling around and I should be done...

Mike
#4

Hello Mike, that's an indication the AGC (AVC on Broadcast) is doing it's job. On weak or no stations the rf amps are biased for max gain, therefore the noise is very noticeable. Strong signals will lower the gain to throttle back the blast. It's "automatic".
#5

Thanks for the reply RodB...

I've enjoyed working on this Philco and I found that replacing the caps weren't as hard as some had mentioned in postings....    This is no Marantz Stereo, but it was probably quite a nice receiver back in the day...

Couldn't find the clear "slip over" caps that went over all the brown pushbuttons, but the P-touch label maker did a nice job...

Went antiquing the other day with the wife and found 3 tube radios...not worth the time though...I guess I'd like the next radio to be more aesthetically appealing, as well as a fun restore...


Thanks for the help from the forum members!
Mike


Attached Files Image(s)
       
#6

Looks very nice!




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