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hum in 116B
#1

I have acquired a hum in my set.
I was going to sell it but pulled it.the shadow meter seems to want to work but does not. moves slightly left or right and stops.
I think it used to work before. If the hum was from a power supply filter,it would be there all the time wouldn't it?

this hum is only on station and in between stations there is no hum.
Does the shadow meter work off of an IF tube?
Where do I start.
David F
#2

Thanks anyway-I will sell it as is.
#3

Many things can cause weird noises in vintage radios. If you havent changed the filter caps yet, that is most likely the source!!! However, common household items such as modern type florescent-lighting near your radio, TVs that are turned on, microwave ovens, clothes washers ( motors put out RF!!), clothes dryers, AC line "hash" coming into your home ( hence, a neighbor down the street firing up his home arc-welder connected to the same overhead pwr lines), ALL cause static & weird hums in vintage tube radios especially if on or near each other at the same time. If the radio has had a complete "re-cap", check your surroundings , turn off all other electrical appliance devices, and try again. If the radio hasnt had a complete recap, the old "filter caps" are telling you to unplug the radio, and sell it before you take-out a pwr transformer, ( if it has one). Just trying to help. Randal




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