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I have revived this 37-620 radio which was a basket case. This is my first radio. I receive BC signals but they are tough to lock, and I receive loud squelching just before I get the signal. Once I get the signal and get beyond the loud squelching, I have to turn down the volume or else it becomes saturated.
I have a single ended antenna connected to Input 1 with 2 connected to ground, it's length is apprx. 12 feet. It is supposed to be some sort of dual antenna with the center tap of the RF transformer grounded.(Input 3)
My thought is that the alignment might be the cause of this issue.
Any thoughts?
Thanks
(This post was last modified: 01-30-2014, 05:15 PM by
John_S.)
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City: Ironton Ohio
A leaking capacitor may cause it to loose a station after it is "locked in"
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It locks in, but will saturate if volume is turned up. Also is very sensitive to adjustments. Before station is obtained squelching is heard that you would normally would not get.
I'm thinking something may be slightly out in the oscillator circuit or the tuning capacitor. Not sure what symptoms would be seen with dirty tuning capacitor, I don't believe what I'm experiencing falls into that category.
Thanks
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City: Ironton Ohio
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City: Tacoma
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Are all the tube shields in place? If not, you can easily get IF feedback which would cause this problem.
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City: Shepherdsville, KY
Hi
Like Brenda said missing tube shields especially the first AF or the IF tubes. Also the cap in the agc curcuit or the cap in the IF tube screen grid bypass also the second filter cap or any of the other filter caps. In other words change out all caps. There are several caps that can cause your problem.
My two cents
Joe
Joe Bratcher near Louisville, KY
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Brenda,
That's a good idea on the shields. I will try to find some for this model. Another question on this model is the antenna setup, is it better to try a loop antenna like the one Philco suggests, or just use a single ended one?
Thanks
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Single ended random wires work well with these sets.