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Old 10th Nov 2019, 10:38 am   #62
Levente
Hexode
 
Join Date: Nov 2016
Location: Budapest, Hungary
Posts: 316
Default Re: Vintage Radio and Phonograph cutter schematic

Quote:
Originally Posted by Levente View Post
Quote:
Originally Posted by ms660 View Post
Just looking back at Post#41, only slight hum was reported, I would check everything done since then and also determine whether the hum is 50Hz (mains, heaters etc) or 100Hz (HT ripple)

Lawrence.
I believe that the hum is 50 cycle. Will re check again, might change the first 8A electrolytic cap too and will test this in another room further away from any other appliances.
CORRECTION:

I think is 100Hz hum. Now I did change the 8A cap also. Now the filter and reservoir cap is the same. Made a small rail for that as It was easier to tie several leads to the rain instead of directly to the cap.

Now, volume down no hum. Volume up massive 100Hz hum.

I think these capacitors I have are not suitable for this.

Shame I only have 275VDC and 350VDC rated one and not 450V.

Would need to order a proper filter and reservoir cap....
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