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

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
FM motorboating on Philco 48-482
Micro9
Junior Member
**
Posts: 36
Threads: 15
Joined: Aug 2007
City: Glendale,AZ
#1

11-01-2009, 10:34 PM
Need help on a Philco 48-482.BC and SW work great after recap but FM is very weak and motorboats when volum is rasied.FM was bad before I recapped it.All resistors are with in tolerance around the FM1000 and 7B6 tube.....Any ideas????
Find
Micro9
Junior Member
**
Posts: 36
Threads: 15
Joined: Aug 2007
City: Glendale,AZ
#2

11-02-2009, 11:53 PM
FIXED.....One of the "NEW" E-caps I put in went belly-up....Checked it before I put it in..It checked good...went belly-up after the power hit it.....
Find
exray
Phorum Expert
*****
Posts: 893
Threads: 9
Joined: Mar 2008
City: Vieques, PR USA State, Province, Country: PR
#3

11-03-2009, 09:00 AM
How did you pin it down? Did it swell up or pop?

-Bill
Website Find
Micro9
Junior Member
**
Posts: 36
Threads: 15
Joined: Aug 2007
City: Glendale,AZ
#4

11-03-2009, 02:34 PM
No I used my ESR meter and started from scratch again....Per the Schematic (I) part of the old Cap went to filter the FM.I cut the orginal cap out of the ckt before I put in a new cap in its place.....The cap looked just Like new but was shorted....
Find
codefox1
Silent Key
*****
Posts: 2,128
Threads: 18
Joined: Oct 2008
City: Merrick, Long Island, NY
#5

11-03-2009, 06:29 PM
Interesting. I have seen problems with motorboating caused by an open filter capacitor quite a few times, but a shorted one would either burn up the dividing resistor or cause the stages fed by it to cease functioning. Glad you got the set working again, but I'm afraid I missed something.
Find
Micro9
Junior Member
**
Posts: 36
Threads: 15
Joined: Aug 2007
City: Glendale,AZ
#6

11-03-2009, 09:13 PM
There was a 3300 ohm R404 that was also burnt. It wasn't open but was @3.5 meg and I replaced that also....
Find
« Next Oldest | Next Newest »
Thread Closed




Users browsing this thread:
[-]
Recent Posts
Philco model 38 code 121 not receiving signal.
Good luck next thing you know you will be winding coils just for the fun of it. DavidDavid — 11:29 AM
Testing a speaker and output transformer Trutone A2-G
morzh Short-circuited turns can be considered as a half-dead transformer. But on this case transformer will hot and s...Vlad95 — 11:01 AM
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

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

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