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41-300 stumped
#1

Doing a restoration on a 41-300, and it seems someone has been here before me long ago (One of the metal caps was swapped for a 3-section 8-8-8 cap wired in parallel for 24 mF).

Anyway, The output from the volume/tone control goes to a terminal with no other wire leading away. The schematic clearly shows a connection to the speaker/field coil, but there aren't any more wires to make that connection. The schematic looks to have 5 connections going to the speaker, but I only have 4 going to the speaker.

A photograph I found online of the underside of this chassis seem to confirm I've got everything hooked up correctly, but I can't see what should be coming off this terminal.

I'll be glad to post the schematics if helpful...
#2

Here is a link to the schematic. It looks like 3 e-caps of 25, 10 & 8 mfd. Not certain as to whether or not they are all in one can or multiple. Is the output transformer mounted on the speaker or chassis? Not apparent from the schematic.
Jerry

http://www.nostalgiaair.org/PagesByModel...013423.pdf

A friend in need is a pest!  Bill Slee ca 1970.
#3

Jerry,

Thanks for responding... My question isn't really about the E-caps, that was just explanation for how I know the radio has had some work done in the past. The e-cap you read as 10uF is actually 18 uF...scan quality of the schematic.

The output transformer is mounted on or near the speaker.

Dave
#4

Certainly confusing to me. As far as I can see (not well note my missreading of one cap value) there needs to be a lot more wires going to the speaker/output transformer combo.
Let's see, first the field coil takes two leads, one of which will also take care of the center tap of the primary of the OPT. Two down.
Next the OPT primary will require two more leads for the ends of that winding. Two more down.
Finally, if I read the schematic right and that area has some missing lines, the OPT secondary requires 2 lines going back to the receiver for feedback and a ground. Three more lines as I can see.
That is a total of 6 lines. I'm obviously missing something here if you only have a four pin plug!
You need better help than me!
Best, Jerry
I will be watching for others comments.

A friend in need is a pest!  Bill Slee ca 1970.
#5

I have one of these that I will be looking at soon.
I will keep up on you thread. Might have some useful info for my project.
Mine powers up and gives me nothing but static and noise. No reception.
Check tubes and replaced the xxl tubes as they tested pretty weak.
Have to check the coils when I get it out of the cabinet.
Good luck with yours.
They are supposed to be good players.
murf
#6

Hi,
Say as long as you have yours apart, how about looking at the band selector side of the dial for me.
Mine has a light that travels up and down as you change bands.
There are little porthole type openings for the light to shine through to designate which band you are on.
Turn the dial all the way to one end and the lower light comes on.
Question is, are the little porthole windows covered with a piece of plastic to block the light from showing through the glass dial?
Mine has them covered. The light comes on when you change bands,but you can't see it from the front to tell you which band your on.
Looks like it is a factory job.
Weird or what?
murf




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