Posts: 668
Threads: 144
Joined: Jun 2011
City: Elko,MN.
Hi Guy's,
Have a question on my model 76 lowboy that I am working on.
WHen I turn it on,without an antenna hooked up,I have a hard time receiving stations.
If I grab the volume control(no knob)it will receive stations.
But only the volume control.
I thought it might be a ground issue,but only happens with the volume control.
No difference on any other controls or the chassis.
If I hook up a wire to the antenna screw it only picks up stations that are the strongest.
Not as good as when I grab the volume control shaft.
Is there some kind of short,or what?
Have the cabinet almost re-finished.Had to make a new top as the old one had a huge hole burned in it.
Looks awsome now.
Would still like to find a new speaker and grill cloth for it though.
If you have anything let me know.
Thanks for your help,
Murf
Posts: 7,283
Threads: 268
Joined: Dec 2009
City: Roslyn Pa
Bet your primary on the antenna coil is open. To check unplug, turn volume full up measure with an ohm meter from antenna post to chassis. If it is OK should read a few ohms (like 10 or less) if not coil is open or the wire on the coil has broken.
Terry
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!
Terry
Posts: 668
Threads: 144
Joined: Jun 2011
City: Elko,MN.
Thank for the info Terry,
Will check it out.
Murf
7estatdef Wrote:Bet your primary on the antenna coil is open. To check unplug, turn volume full up measure with an ohm meter from antenna post to chassis. If it is OK should read a few ohms (like 10 or less) if not coil is open or the wire on the coil has broken.
Terry
Posts: 163
Threads: 8
Joined: Jun 2011
City: Chicago,illinois
Hi Murf, I was on the antique radio grill cloth site the other day to place an order. John has the tapestry cloth...if that's the one you looking for.
Posts: 668
Threads: 144
Joined: Jun 2011
City: Elko,MN.
[Do you have the website address?
Will check it out
quote="Chicago Jimmy"]Hi Murf, I was on the antique radio grill cloth site the other day to place an order. John has the tapestry cloth...if that's the one you looking for.[/quote]
Posts: 668
Threads: 144
Joined: Jun 2011
City: Elko,MN.
7estatdef Wrote:Bet your primary on the antenna coil is open. To check unplug, turn volume full up measure with an ohm meter from antenna post to chassis. If it is OK should read a few ohms (like 10 or less) if not coil is open or the wire on the coil has broken.
Terry
Checked it out as you said and it reads about 34 ohms.
Bad coil?
Posts: 163
Threads: 8
Joined: Jun 2011
City: Chicago,illinois
Posts: 668
Threads: 144
Joined: Jun 2011
City: Elko,MN.
Chicago Jimmy Wrote:Murf, Here it is..
http://www.grillecloth.com/ Thanks for the info,
Looked him up and ordered new grill cloth.
Murf
Posts: 668
Threads: 144
Joined: Jun 2011
City: Elko,MN.
murf Wrote:7estatdef Wrote:Bet your primary on the antenna coil is open. To check unplug, turn volume full up measure with an ohm meter from antenna post to chassis. If it is OK should read a few ohms (like 10 or less) if not coil is open or the wire on the coil has broken.
Terry
Checked it out as you said and it reads about 34 ohms.
Bad coil? Not even sure what this coil looks like.
Anyone have a picture?
Posts: 668
Threads: 144
Joined: Jun 2011
City: Elko,MN.
murf Wrote:murf Wrote:7estatdef Wrote:Bet your primary on the antenna coil is open. To check unplug, turn volume full up measure with an ohm meter from antenna post to chassis. If it is OK should read a few ohms (like 10 or less) if not coil is open or the wire on the coil has broken.
Terry
Checked it out as you said and it reads about 34 ohms.
Bad coil?[/quot
Looks like 4 coils in cans.
How would I know which one is the culprit?
Looking at them from the bottom,looks like all wires are attached.
The windings look like they are covered with looks like bubbled shellac?
Almost looks shiny like melted solder,but I'm sure thats just the way the light hits it.
WHat do you guys think?
Thanks for the help.
New discovery,
If I touch the top lead on one of the 24 tubes it receives well.
It has 3 24 tubes.
Would this indicate that that coil is bad?
Murf
Posts: 7,283
Threads: 268
Joined: Dec 2009
City: Roslyn Pa
Seems a bit high. Would pull it out and have a look at it checking for green spots.
Terry
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!
Terry
Posts: 7,283
Threads: 268
Joined: Dec 2009
City: Roslyn Pa
So go here: http://www.nostalgiaair.org/PagesByModel...040192.pdf
This is the service info for your set. Look at the tube layout diagram and tell me which tube you can touch to make your set receive stations. We'll go from there.
Terry
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!
Terry
Posts: 668
Threads: 144
Joined: Jun 2011
City: Elko,MN.
Hi Terry,
Its the 24 tube closest to the antenna terminal.
I have almost finished refurbishing the cabinet,and would like to get this fixed before I put it back in the cabinet.
Your help would be greatly appreciated.
Thanks
Murf
Posts: 7,283
Threads: 268
Joined: Dec 2009
City: Roslyn Pa
Funny thing is the diagram doesn't show a volume control. I don't have a picture of the chassis so trace your wire going from the ant. post should go to the volume control and then to the rf coil. That's the coil you want to have a look at. Draw a diagram of how the wires are connected then unsolder it. Remove the fastening screw and remove the coil. Inspect for green spots(rot) or broken wires.
Terry
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!
Terry
Posts: 668
Threads: 144
Joined: Jun 2011
City: Elko,MN.
OK,
Will check it out.
Know where I can get a coil if needed?
Thanks
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