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I'm restoring a Silvertone Model 1908. After re-capping, the radio works but is very noisy. Off station there is a loud buzz (~ 180 Hz). On station, the buzz is mostly gone but the audio is still not clean. AVC voltage is ~ -6V on a strong signal. Off station the buzz is louder than the station but the AVC is only - 3V. The buzz originates prior to the audio stage.
Any suggestions would be appreciated. BTW, of all the radios I've worked on, the Philcos are the easiest to restore and seem to work better than other brands.
Thank you.
Don
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Don
First, you should move that thread to "Other Radios".
As for your problem, you might have a case of interference, like switching power supplies, CCFL light bulbs etc.
See if you could eliminate those first.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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Thread moved to Other Radios section.
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City: Roslyn Pa
+1 Mike
Try connecting an earth ground to the chassis like from a water pipe or baseboard heat element not the outlet ground pin (if it is a transformerless set use a cap to gnd).
If this lowers the noise good chance that it is some sort of local interference. Laptop and cell phone chargers are the worst offenders here at my place but there are many others.
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!
Terry
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Thank you. I had forgotten that I changed my work light to a CCFL. With the CCFL replaced, no noise.
Just needs a good alignment.
Sorry about placing in the wrong folder.
Don
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Kerosene lamp is the best source of light. And is very EMI quiet
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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...plus giving you a bit of extra heat over the winter. Especially if it is an Aladdin kerosene lamp.
--
Ron Ramirez
Ferdinand IN
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City: Roslyn Pa
Dietz are kinda stinky and not all that bright.
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!
Terry
Posts: 15,818
Threads: 554
Joined: Oct 2011
City: Jackson, NJ
Are you insulting Germans?
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
Posts: 7,285
Threads: 268
Joined: Dec 2009
City: Roslyn Pa
9 !!!!!!
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!
Terry