Well, I got looking again on the finish on this radio
and I believe it's been painted!
I can chip off small flakes on the edges of where
the bare spots are.
At least the chassis seems to be in pretty good shape.
The only thing that will give me some headaches
is one of the broadcast band coils is all messed up
by someone in the past poking around in there
and tearing through the windings.
Will have to be re-wound. I hope someone
here knows about how many turns should
go on.
When I get the coil out I can give more details
on which coil it is etc...
Shouldn't be a big deal if I can find out the
number of turns to put back on.
Worked more on it tonight and got the
IF strip and audio section working.
I can inject a 470 kHz AM modulated signal
into the front of the IF strip and it comes out
clean at the speaker!
Regarding photos: The Phorum 101 section is your friend. Too many people never see this important Phorum section because you have to scroll down all the way to the bottom of the Phorum homepage to find it. (Hmmm, maybe I should put it at the top and move the regular discussion forums to the bottom...naah, then people would think the Phorum has gone out of business.)
Finally, to answer one of your questions: No, the grille cloth you have is not original. Get some of Kenny Richmond's chevron cloth put in that cabinet...once you refinish it, that is...
Wow! It is sure nice looking! I did find some similar
pictures online.
Mine needs alot of work then...
UPDATE:
Just hooked up the RF chassis tonight
(separate on the bench with long wires) and
the radio works on all bands!
I'm pretty sure the messed up coil is the
Broadcast Antenna Coil which is probably
the best one to be messed up if one has to be...
Can anyone give me a 2 cent description of how
the shadow meter is supposed to work? I get
no deflection of the internal vane. I assume I
am supposed to get this??
Now to find the right rubber bushings to re-mount
the RF chassis into the main chassis...
Yes, you should get deflection on the vane. Depending upon the particular radio, there may be a resistor across the shadow meter, and the meter could be open. Alternatively, the vane could be frozen (more like sticking), I've had good luck using a small spritz of Liquid Wrench on the vane itself to free it up. A third possibility is that the magnet may have lost gauss, and need to be remagnetized.
OK, thanks for the info. I have not even ohmed out the shadow meter coil yet so I guess that's the first step.
I am a little unsure if I got the coil wires put back in the right way.
I don't know if polarity matters or not but am suspecting that it
does matter so that may also be my problem.
Now to tackle the Broadcast Band antenna coil. One of the
windings is destroyed, any idea where I could find out how
many turns it should have?
I finally took out the Broadcast Band antenna coil and
it turns out that the messed up coil was the primary winding
which only had about 30 turns of wire on it. The secondary
was all good (had hundreds of turns).
I used some #32 magnet wire and got it all re-wound, and put back.
I now get MUCH better reception on the broadcast band!
Also, I read up on the shadow meter and discovered that one can slide the coil forwards or backwards to set the shadow offset. (I have the "New style" shadow meter).
So, I tweeked that and now the shadow meter is working much much better also.
Final step is to order a set of rubber bushings for the RF chassis and I think that will about do it for the electronic restoration.
Now to tackle that horrible cabinet!
Herb S.
Ithaca NY
(This post was last modified: 01-05-2014, 02:49 PM by hsusmann.)
I noticed that the two 6F6 output tubes are wired in what I consider a strange way. They don't have a separate phase splitter, they seem to be using one of the 6F6's screen grid to generate the 180 degree out of phase drive to the other 6F6's grid.
They use a 3500 ohm dropping resistor to the first 6F6's screen and then
AC couple that screen to the grid of the second 6F6. The second 6F6's screen is tied directly to the screen voltage line.
Kind of a clever trick I guess, I just never have seen this in any book
before, even the books from the 30's and 40's.
Does anyone have any info on this technique?
Certainly saves either an extra tube or another audio transformer...
Phase splitter works OK this way PROVIDED the tubes are OK and pretty closely matched, and did save a stage. So long as all the caps and carbons are replaced, leave it be.
I'm like you. Decent on the 'tron wrangling, but not so much on the wood-working. Since the cabinet seems to be in poor shape, I'd take it on as a learning project without a second thought. You can't mess it up much worse than it is unless you set it on fire or drop it out the second story window. I'd be willing to bet you have a whole new feeling about it once you carefully get rid of that horrid paint job and see the bare wood.
It's not how bad you mess up, it's how well you can recover.
That cabinet might not be in as bad as shape as you think. You won't know for sure until you get it stripped. Mine looked a lot worse than it turned out to be and now I am proud to display it. One thing for sure, when you get it up and running, they are good sounding and playing radios. It will be well worth the effort.
Here are some photos of mine..
Before..
After.. It will be a big job, but you will end up with a beautiful radio.