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>Hope to get out to work on it later today...grass mowing first
If it were mine I would be mowing the grass, cleaning the attic, garage, basement, rearranging my sock drawer, get a haircut and have a nice hearty meal.[Image: https://philcoradio.com/phorum/images/sm...on_lol.gif]
Is it going to be a long term project??
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
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I don’t know if it will be a long term project or not, but I did put off working on it yesterday so it probably will take awhile. Perhaps once I understand how it’s been wired up I’ll be more comfortable with it! It will just take some time for me to work through it.
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I was having trouble tracing wires because this set is so packed so I began clipping things out. The volume/on-off control did not operate properly so that came out first. It just would not clean out with contact cleaner (on-off was not working) so it had to come apart.
[Image: https://www.dropbox.com/s/nijf14ip2j2qmx....jpg?raw=1]
It just took a little direct cleaning of the contacts to get it working.
I then clipped out what I thought was Cap#25 (in post #11) and it turned out that it was actually a dual cap with the second positive lead hidden directly underneath. That mean that electrolytic is actually Caps # 23 & 24 in the schematic and are the "missing" filter caps.
That realization made me feel better about this set. So far I've found two modifications in addition to the removal of the speaker field coil (which is 53A on the schematic...tell me if I'm wrong...). The pins 3 & 4 (the two cathodes) of the 25Z5 rectifier have been connected together right on the socket. In addition the volume control pot has the wiper arm connected to trimmer #11 (which I don't think makes a big difference since the pot is a 3meg instead of the 500k called for in the schematic. I have read other restorations on this model that had a similar 3meg volume pot so it may have been a factory mod. You can see the physical connection in the photo above).
I've captured the changes in the following schematic where the green is the added connections and the red Xs are the cut out field coil:
[Image: https://www.dropbox.com/s/g434fq4ps8qq3j....jpg?raw=1]
The set has a filter choke that is separate from the field coil and it looks to me (at least so far) like the previous repair simply cut out the field coil when installing the PM speaker. Does that make any sense? Could that be why they tied the rectifier cathodes together? I have yet to find cap#25 but now suspect I won't find it since, if my thinking is correct, we now have a half wave rectifier instead of a full wave.
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Ok so how it worked was the rt side the the rectifier tube powered the field coil only. By connecting the two cathodes together and eliminating the fc both sections of the rectifier tube power the chassis and 25 is replaced by 23. You don't need to replace the fc w/a resistor as it's not in series w/the hv, it was in parallel.
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
(This post was last modified: 04-28-2020, 09:24 PM by Radioroslyn.)
Posts: 5,010
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Joined: Nov 2012
City: Bandon
State, Province, Country: OR
Thanks Terry! 
Posts: 5,010
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The recapping has begun. I decided to stuff the old caps. The 4 visible caps (the easy to access ones!) have been stuffed. Yep, the chassis is rusty and dirty. If I actually get it working I'll do some more cleaning. This might have been a good candidate for taking all the wires and components off and doing a full derusting...but I'm not going to do that... 
[Image: https://www.dropbox.com/s/a14ram9rwoima6....jpg?raw=1]
I came to one of the "stick" caps that Russ mentioned in an earlier post. It turns out this is actually a double cap, two 0.1uF segments with the lug around the cap being the common lead. We'll have to see if I can get this thing apart in reusable form. Any advice is welcome...
[Image: https://www.dropbox.com/s/9oihccjgiyu00c....jpg?raw=1]
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Bob
Not sure what it is, but your first two links do not work.
The last one does.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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Hmmm...thanks. Post #21 should be a photo of four stuffed caps in the chassis, a single “stick” cap and the only other link is in the signature linking to my restorations page.
Does anyone else have a problem seeing these photos? Thx.
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Looks OK here.
Paul
Tubetalk1
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Joined: Dec 2009
City: Roslyn Pa
Looks OK over here too after a few seconds, the 8080 processor is showing it's age[Image: https://philcoradio.com/phorum/images/sm...on_sad.gif]
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: 15,307
Threads: 530
Joined: Oct 2011
City: Jackson, NJ
Now I see them.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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Joined: Nov 2012
City: Bandon
State, Province, Country: OR
Thanks guys!!
Posts: 5,010
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Joined: Nov 2012
City: Bandon
State, Province, Country: OR
I heated one end of the stick cap with the heat gun and gave a pull on the wire lead on that end. The guts slid out without too much effort and the result is below. In the upper right you can just see a dark wire coming out of the tube. This is copper braid that is connected to the common lug in the center. Fortunately it remained in place and connected:
[Image: https://www.dropbox.com/s/f2jornhh6rapi9....jpg?raw=1]
The stick part is a wooden dowel with the foil and insulator wrapped around it. I started unrolling it here:
[Image: https://www.dropbox.com/s/sbb18vvw57l32m....jpg?raw=1]
When I got down to the wooden dowel, there are metal caps on each end with the wire leads soldered into them. I sawed off the caps from the dowel, drilled out the wood (with some picking with a small screw driver) and unsoldered the wires. Two 0.1uF caps were connected to the common copper braid and then longer wire leads were added to each cap. I used some electrical tape and shrink tubing to keep all the connections separated and then stuffed the two caps into the cardboard tube. A bit of swearing, soldering, resoldering, re-resoldering, more swearing and the leads were soldered into the metal caps and then the little wax covered cardboard ends were fitted over the metal caps. One end looks very original, the other..not so much but for the first time I'm happy. Here is the end product:
[Image: https://www.dropbox.com/s/p4kwhw1h2h0wj3....jpg?raw=1]
One more exactly like this and another double 0.02uF cap. Then it will be back to stuffing the more familiar paper tubular caps.
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You could reuse those metal cylinders to make it look even more authentic. Should be easy.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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I should have taken more pictures. The metal caps are present it’s just that they are covered by the smaller cardboard tubes covered in wax
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