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

Loud hum when i turn on my Model 70
#1

All the tubes light up but all I hear is a loud hum. 

Adjusting the volume does nothing. 

Any ideas?
#2

First and foremost, DO NOT power up old radios until the capacitors and any drifted resistors have been replaced. Components in old radios degrade with age (especially capacitors), and can cause damage to other components (most which are much more expensive and harder to find). Caps are relatively inexpensive and replacing them will help keep other parts from being overloaded. Take care and BE HEALTHY! Gary

"Don't pity the dead, pity the living, above all, those living without love."
Professor Albus Dumbledore
Gary - Westland Michigan
#3

+1 what Gary said. Here's some more information courtesy of this site:

https://philcoradio.com/library/index.ph...urn-it-on/

Bottom line, your radio will need some components replaced under the chassis before it will play without that loud hum.

Greg V.
West Bend, WI
Member WARCI.org
#4

Welcome to the Phorum!
Icon_wave

The capacitor and resistor replacements are not too difficult especially if you have a little knowledge about soldering and electronics. If not, questions to the group here can help you through it or you can find someone to do the restoration for you.
#5

From what I have read, the hum is most likely caused by the old electrolytic filter capacitors. Those are very important and should be replaced.




Users browsing this thread:
[-]
Recent Posts
Need to purchase some accessories for restoration of my Old Philco Radio
Here is a list of resources found in our online library that you might find useful. Mike's Gobs of Knobs email addres...klondike98 — 01:46 PM
First Radio restoration
Hi Tubeman, Welcome to the Philco Phorum.  Phamily Phriendly Pfun with Phine Pholks Phull of Philco Phacts. (See a p...MrFixr55 — 12:33 PM
First Radio restoration
You could post in the WANTED ADs section here on the Phorum and see if anyone has an RF generator that they want to sell...klondike98 — 11:55 AM
Zenith H725
Good ideas, thank you Arrange and Rich. I have the adhesive aluminum foil already and can try that immediately. More ...EdHolland — 10:18 AM
Graphics for majestic 1050 dial glass.
Murf; I found this thread on the ARF, the first photo has a pretty good view of the dial glass. Regards ArranArran — 01:12 AM
Zenith H725
hello Ed, how about that speacial tape used for ducting it's like foil or how about thin piece of aluminum roof flash...radiorich — 12:19 AM
Zenith H725
Ed; One material that I have seen, but never tried for this was material for making exhaust gaskets, it's similar to ...Arran — 11:42 PM
Zenith H725
I just remembered, I have some hi temp silicone rubber material which could do the trick. Or a piece of FR4 laminate. Th...EdHolland — 08:39 PM
Zenith H725
The PSU filter cap arrived today (thank you USPS!) so I will work on that later. Meanwhile, I have the dial, speaker...EdHolland — 06:42 PM
Philco 610B oscillator wiring
Thanks Terry. After checking my notes I think I recorded about -10v at the 6A7 G4/control grid. The screen grid (G3 &...Tubester — 05:59 PM

[-]
Who's Online
There are currently 2625 online users. [Complete List]
» 2 Member(s) | 2623 Guest(s)
AvatarAvatar

>