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Old 05-15-2015, 04:20 PM
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DavGoodlin DavGoodlin is offline
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Join Date: Aug 2011
Location: near Strasburg PA
Posts: 3,501
Magnavox OFM022 AM-FM question

I got a customer set that resembles a trapezoid from the top. There is no sams for it but I have one of my own in a different cabinet with better speakers.
IMG_6510.jpg
The trapezoid was dead and had a 12BA6 where a 12BZ6 was shown on the tube location label.
I found three resistors burned beyond ID of color, so I grabbed my set to get ID and installed the right replacements. A shorted electrolytic likely fried them, so those were replaced. After replacing 3 paper caps (elmencos, while mine has bumblebees), a selenium rectifier, X2 safety cap, 50EH5, 12AV6 and a 12BZ6, it fired right up. The FM was fair but AM receives well and sounds awesome, like a Magnavox should! It seems that when tuning FM, there are two peaks but its fuzzy right in the middle where the tuning meter peaks. This is the case on both strong or weak FM stations.

The question I have is this: I see only 2 IF cans and a discriminator trans whereas most AM-FM sets have 4 IF transformers and a disc. trans. How can I align this set without a schematic? I don't know which IF is which. Most sets have a set of AM and FM transformers, sharing a tube for each stage. Does anyone have an idea how this set was Muntz'ed down to so few components?
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