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Need Help with 49-405 Electronics
#16

I tried replacing the resistor with a choke The smallest thing I had was the original audio output transformer from this set. I had replaced the original speaker/transformer assembly with one from a model 46-250. That didn't change the hum, but I may be on the wrong track. I need to learn something about hums. The only time I was successful in subduing a hum was a Philco Model 87, which had a hum adjuster on the upper chassis.

This hum starts almost the instant the power is on--no lag for warm-up--and it's unaffected by the volume control.

Regarding the K3KU mystery, I assumed that in code it would show some symmetry or pattern. Maybe it has some meaning backwards. I'll send it over to the NSA Cryptography Institute.

- Henry --I won't tell you how old I am, but we are three brothers, less than 3 years apart, and I'm the baby. Art was the smart one.


Messages In This Thread
Need Help with 49-405 Electronics - by Winky Dink - 11-08-2015, 04:03 PM
RE: Need Help with 49-405 Electronics - by Winky Dink - 11-14-2015, 06:39 PM
RE: 49-504 Trimmer Trouble - by Winky Dink - 11-19-2015, 04:18 AM



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