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

Philco 37-660 Hum
#1

Finally got into working on this radio after a few years of ownership and letting it sit. Replaced Electrolytics - what a pain on the ones in the RF section!! I am now picking up stations very well but have a residual issue - low grade hum. This is not the obnoxious that existed before the original electro's were replaced but it is enough to be distracting. I have been going through replacing the other paper caps - and have not gotten into bakelites as of yet - could one of these be the culprits or is there something else I should be looking at?? Before I moved onto other projects I thought I'd look to the experts and see if I'm missing something that can bring this to a solid working state.
#2

If you haven't recapped the rest of the radio there maybe a leaky cap or two or three drawing excessive current. It is possible to have a bad tube with heater/cathode leakage. Check the 6F6 tubes, if one is really weak that could cause some hum. Just some thoughts.

Gregb
#3

Does the hum change when tuned in?
#4

The hum still exists when tuned in. I did notice when not on a station and varied the volume the hum would minimize then return. I'll look at the options described above and if any other suggestions feel free to chime in.

Tx. Mike
#5

What you have not answered is whether you did full recap.
#6

Gm

Did not do a full recap but did find issue- neg of 8uF electro caps was on chassis- once corrected now functions as should. I also as a precaution checked all tubes and all tested in tolerance.

Thank all for assist and direction!
#7

Are you sure the neg should not be on the chassis?
Post the link to the sch, it will make it easier.
Again.

Do the recap.
Do the recap.
Do the recap.




Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
philco predicta
Welcome to the Phorum, cgl18! I am not your resource for television repair, but lots of friendly help is available here...GarySP — 02:12 PM
Model 70 Cabinet Trim
Welcome to the Phorum, musar! You can send Steve Davis a private message (PM). The site is at the top of the Home page...GarySP — 02:09 PM
Model 70 Cabinet Trim
How do I contact him? The only contact information for him I could find when searching online was a telephone number th...musar — 10:38 AM
philco predicta
Hello, good afternoon, I would like to ask what the possible problem could be if I don't have an image on the screen. I ...cgl18 — 10:19 AM
Philco model 38 code 121 not receiving signal.
So one last question before I finish this radio. Regarding the speaker and output transformer. I salvaged the original o...Stormlord5500 — 09:31 AM
462ron
It’s on the bottom of the homepage of our Philcoradio.com homepage! Ron462ron — 07:20 AM
Model 70 Cabinet Trim
Steve might have some trim left. Not sure he is making anything.morzh — 06:12 AM
Model 70 Cabinet Trim
Hello musar, First all welcome to the forum and yes that is true that steve stopped making trim . Sincerely Richar...radiorich — 12:13 AM
Model 70 Cabinet Trim
I have recently come into possession of a Model 70.  The trim around the base needs to be replaced.  If this were years ...musar — 12:07 AM
philcorepairbench.com - shadow-meter
Anyone know of a way to recover these files from the repair bench? Thanks. fenbach — 11:16 PM

[-]
Who's Online
There are currently 1997 online users. [Complete List]
» 1 Member(s) | 1996 Guest(s)
Avatar

>