1. The PHILCO Phorum
  2. Various and Sundry Categories
  3. Vintage Hi-Fi, Stereo and Audio

Welcome Guest! Be sure you know and follow the Phorum Rules before posting. Thank you and Enjoy! (January 12) x

Thread Closed
Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

Threaded Mode
Ampeg J-12D
vecher
Phorum Expert
*****
Posts: 933
Threads: 140
Joined: Mar 2015
City: Lansdale State, Province, Country: PA
#1

09-02-2021, 11:32 AM
Does anyone have any information on this amp.. I replaced all caps .. when i turn it on... no mic connected its quite .. no hum.. but when i plug in a mic i get a load hum when i turn up the volume its a metal case mic as soon as i touch the mic the hum comes.. any clue on why? grounding ??

Skip
Find
Radioroslyn
Phorum Expert
*****
Posts: 7,301
Threads: 269
Joined: Dec 2009
City: Roslyn Pa
#2

09-02-2021, 11:56 AM
https://ampeg.com/support/files/Schemati...ematic.pdf
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
Find
« Next Oldest | Next Newest »
Thread Closed




Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
Testing a speaker and output transformer Trutone A2-G
I am not sure how a transformer could be weak. It could be inadequate, but only when you replace the original with somet...morzh — 09:56 AM
Philco model 38 code 121 not receiving signal.
Good news everyone! I think I have found everything I need for rewinding the antenna coil primary. I found some pla...Stormlord5500 — 09:40 AM
Philco Battery-WWII vintage
My younger sister went to SUNY Plattsburg NY, (BS, MS, RN) in the late 1970sabout 10 min from the Northern NY / Canada b...MrFixr55 — 07:59 AM
Philco Battery-WWII vintage
Hello Bob, What Amazing find! Sincerely Richardradiorich — 10:19 PM
Testing a speaker and output transformer Trutone A2-G
Hi Murf, Do this: Monitor between ground and one plate of the rectifier while playing the radio.  Do the same with ...MrFixr55 — 09:51 PM
Philco Battery-WWII vintage
Mike; I take it that Soviet cars did not come equipped with block heaters, hence the hot oil change? Where I lived in...Arran — 08:42 PM
Philco 42-345 Restoration/Repair
The more the better. (Within reasonable limits.) 2-5 times more is no problem in this case.Vlad95 — 03:50 PM
Philco 42-345 Restoration/Repair
Thanks, RodB and Vlad95, I was mainly trying to figure out this capacitor to locate a replacement, Vlad thank you for...osanders0311 — 03:44 PM
Testing a speaker and output transformer Trutone A2-G
Would an output transformer if weak, cause the problems I am seeing with lower B+ voltage? murfmurf — 01:22 PM
Testing a speaker and output transformer Trutone A2-G
Hello murf! I merged the threads. Please do not start new threads regarding the same radio. Take care, - GaryGarySP — 10:21 PM

[-]
Who's Online
There are currently 691 online users. [Complete List]
» 1 Member(s) | 690 Guest(s)
Avatar

>
  1. The PHILCO Phorum
  2. Various and Sundry Categories
  3. Vintage Hi-Fi, Stereo and Audio