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

Philco 42-1013
#1

Have this thing re-capped now and it does play.
I don,t seem to have the volume I would like,and if you turn it up to about 1/2 volume it starts getting distorted and the volume does not really go up.
Someone replaced the volume switch with a combe on/off/volume switch due to a bad switch on the off pushbutton.
I wonder if the switch is under-rated for that chassis,or if there could be something else I should be looking at like maybe a tube?
This one has been a bear for a newbie like me to work on.
Any idea's?
Thanks again,
murf
#2

You picked a difficult set to start out. As far as distortion, I would make basic voltage checks in the audio section with emphasis on the audio output bias. Should be about -20V on the control grids of the 7C5s. Also make voltage readings on the other tubes in the radio too. Often problems can be found this way without elaborate test equipment. If basic voltage checks are good then alignment will have to be considered.

Concerns about a under-rated switch is misplaced. Tubes are usually Ok. These being locktal tubes there is concerned about pin connection issues. Rocking the tubes in the sockets can reveal a intermittent pin while listening to the radio.

http://www.nostalgiaair.org/Resources/497/M0013497.htm
#3

rghines1 Wrote:You picked a difficult set to start out. As far as distortion, I would make basic voltage checks in the audio section with emphasis on the audio output bias. Should be about -20V on the control grids of the 7C5s. Also make voltage readings on the other tubes in the radio too. Often problems can be found this way without elaborate test equipment. If basic voltage checks are good then alignment will have to be considered.

Concerns about a under-rated switch is misplaced. Tubes are usually Ok. These being locktal tubes there is concerned about pin connection issues. Rocking the tubes in the sockets can reveal a intermittent pin while listening to the radio.

http://www.nostalgiaair.org/Resources/497/M0013497.htm


Voltages were checked as well as audio output.All seem fine.
Have had tubes out for cleaning and testing.
Is there a way to check the volume switch that was replaced?
Thanks for the help.
murf
#4

Little hard to read the schematic. Thinks it reads 2 Meg total with a 1 Meg tap. Believe the tap is for improving bass at low volume. Beginning to think the volume control replacement was poorly executed. Verify resistance and presence of a tap on the replacement and associated wiring. Not unusual to see poorly done vintage repairs for parts shortages, etc. Might find a replacement if needed from Mark Oppat at oldradioparts.net.
#5

rghines1 Wrote:Little hard to read the schematic. Thinks it reads 2 Meg total with a 1 Meg tap. Believe the tap is for improving bass at low volume. Beginning to think the volume control replacement was poorly executed. Verify resistance and presence of a tap on the replacement and associated wiring. Not unusual to see poorly done vintage repairs for parts shortages, etc. Might find a replacement if needed from Mark Oppat at oldradioparts.net.


Will check it out when I can.
Thanks again




Users browsing this thread: 2 Guest(s)
[-]
Recent Posts
Bakelite crack repair - what is best epoxy?
Starting on a Philco 48-1401 Boomerang radio/phonograph.  It has one crack on the left side running from the speaker ope...de371 — 07:17 PM
Philco 89B code 123 newbie
Progress continues, finished blocks 9 and 26.  I wonder for caps 23 and 24—can I get away with 100pf instead of 110pf? ...Kurt P — 03:43 PM
Looking for place to donate unique Philco Philco J-1930 Prototype
Welcome to the Phorum, jeibner. Several of our members have connections with radio-related museums. I'm sure others wi...GarySP — 03:41 PM
Looking for place to donate unique Philco Philco J-1930 Prototype
I'm looking for a museum or other permanent home where I can donate a unique Philco prototype of a very top of the line ...jeibner — 03:15 PM
Test bench almost done...
Sweet! Yes, that's a lot of planning and work but will pay off! I built mine about 10 years ago using a radio book from ...TV MAN — 11:39 AM
1950 Emerson TV resurrection attempt
Been awhile since I've even been in the radio room. Work work work, kids graduating, going into college, and the list go...TV MAN — 10:35 AM
Philco 269 - 444 FIVE VALVE VERSION?
> So, given that this is a major refurb I don't have the time to spend on this, so happy to pass it on to someone who...Radioroslyn — 09:08 AM
Philco 269 - 444 FIVE VALVE VERSION?
Thanks for this  Hi Chas, Fix it, don't bin it! Don't sell your skills short. One step at a time and like the Home D...ChasL0001 — 01:48 AM
Philco 84 antenna connection
Have a Philco 80 my long wire is app 30 feet, for a ground in my work shop have a ground rod that is used only for radio...David — 07:47 PM
Philco 46-480 Cabinet Restoration
Thank you, Gary! I appreciate it.jrblasde — 07:24 PM

[-]
Who's Online
There are currently 2963 online users. [Complete List]
» 2 Member(s) | 2961 Guest(s)
AvatarAvatar

>