1. The PHILCO Phorum
  2. Philco Radio Discussions
  3. Philco Electronic Restoration
Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

Linear Mode
91-121 push pull output hum
jcassity
Senior Member
****
Posts: 619
Threads: 42
Joined: Mar 2017
City: Gap Mills Wv 24941
#3

11-07-2017, 11:04 AM
using an oscope if you have one , connect to your expected dc voltage points and determine where the highest AC ripple is.
A stray excessive ac ripple could honestly be just about anywhere.
Find
« Next Oldest | Next Newest »


Messages In This Thread
91-121 push pull output hum - by grandntl - 11-07-2017, 09:46 AM
RE: 91-121 push pull output hum - by morzh - 11-07-2017, 10:28 AM
RE: 91-121 push pull output hum - by jcassity - 11-07-2017, 11:04 AM



Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
HiFi (Chifi) tube amp build - but my own design.
And so does a barber shop quartet. mmmmmmRodB — 03:54 PM
Shadow Meter Bulb
I did try an LED bulb in place of the original but wasn't impressed with the amount of light on the dial. Seems like it ...RodB — 03:51 PM
HiFi (Chifi) tube amp build - but my own design.
Tim Would mounting he transformer vertically change the hum, if used without additional parts? Also, in these amps...morzh — 02:25 PM
Shadow Meter Bulb
Gary I doubt it would introduce any noise. We use similar lamps for the panel indication, 12V AC lamps: they are LEDs...morzh — 02:15 PM
Shadow Meter Bulb
Not sure if anyone has tried this but there are 6.3 volt miniature lamps in bayonet and screw-in base options available ...GarySP — 11:31 AM
Shadow Meter Bulb
Any 6.3 volt pilot light will work. I would use the brightest one I could find in my workroom. Be sure the dial is clean...RodB — 10:45 AM
HiFi (Chifi) tube amp build - but my own design.
Tim, nice write up and thanks for sharing !! Sincerely Richardradiorich — 02:47 AM
HiFi (Chifi) tube amp build - but my own design.
Well, this was a real "Hum-Dinger" :lol: ! This will be kinda long, but hopefully it will help others having t...TV MAN — 01:55 AM
Shadow Meter Bulb
Phorum members, I am trying to find the bulb # for PHILCO Shadow Meter part number 45-2180 that is from a 37-640 chassis...georgetownjohn — 06:53 PM
Philco 41-608 changer coupler
3D-printing...short of machining, of course. Or molding.morzh — 05:20 PM

[-]
Who's Online
There are currently no members online.

>
  1. The PHILCO Phorum
  2. Philco Radio Discussions
  3. Philco Electronic Restoration