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 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: 1 Guest(s)
[-]
Recent Posts
Atwater-Kent 84, restoration.
Rich yes, this is the way I got it. I have just put it on the table and took it apart. I suspect it even might work,...morzh — 11:31 PM
Atwater-Kent 84, restoration.
Hello mike, What nice looking radio I have one AK in my collection it's a console I have not started restoring it yet ....radiorich — 11:21 PM
91H Code 126 Restore
Just to make it more confusing here is another model 91 schematic that doesn't show parts with dotted lines in that spot...Arran — 10:37 PM
Atwater-Kent 84, restoration.
The wires were desoldered from the can, and the capacitors checked. All checked at 0.102 uF, which is correct. So the c...morzh — 09:41 PM
An attempt to remove the Field Coil from a G speaker
Arran Yours probably then the H speaker, same as mine.morzh — 08:39 PM
An attempt to remove the Field Coil from a G speaker
Mike; I would like to have a look at the speaker in my model 96, but the set is packed into a corner in the basement. ...Arran — 08:04 PM
91H Code 126 Restore
Thanks Arran, I'm convinced the power cord is good but have a nice repro plug for it. Would it be prudent to add a fus...RealRider — 07:28 PM
91H Code 126 Restore
As I was studying this schematic I was wondering what does this dotted line means?  I haven't traced it out yet. An o...RealRider — 07:22 PM
91H Code 126 Restore
When it comes to the cloth covered power cords, if they are not frayed, and are flexible, and if I can bend one without ...Arran — 06:21 PM
An attempt to remove the Field Coil from a G speaker
Could be. The central cylinder is OK, but the sides are...well. What's done is done. I wonder if some standard bobbine w...morzh — 06:02 PM

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

>