Philco 18 changes - Printable Version
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Philco 18 changes - DKinYORKpa - 01-09-2013
I just got my schematics from Chuck for the early 18 model. None of changes that I see on my chassis are listed. So I'd like some opinions! (1) the 2/2/1 electrotyic on mine is a 3/3/2. It has a Philco part # and a penciled-on price of, I believe, 85 cents. This could just be a replacement, correct? And should I use those values to restuff it? (2) A change is listed for the 8 & 10 electrolytic cans as replaced with a single 8/10 can. I have a Solar 20/20/20 can. The third 20 is 25V and goes to chassis ground. What values should I restuff this can with?
RE: Philco 18 changes - DKinYORKpa - 01-10-2013
Anyone?
RE: Philco 18 changes - Ron Ramirez - 01-10-2013
(1) Someone replaced your original 2/2/1 with a 3/3/2. You can use 3.3, 3.3 and 2.2 to replace it...or 2.2, 2.2 and 1 uF. It will not make a difference.
But do use 450V rated caps here.(2) Yes, the original separate 8 uF and 10 uF caps were replaced with a single 8 uF/10 uF can. You should replace with a 10 uF, 450V cap in place of the original 8 uF.
Now, the original 10 uF cap was in the B- (bias) circuit. Here, you want to use a 10 uF, 50 volt cap. On this one, the positive is connected to ground, and the negative is connected to B-.
RE: Philco 18 changes - DKinYORKpa - 01-10-2013
Quote:Yes, the original separate 8 uF and 10 uF caps were replaced with a single 8 uF/10 uF can.
Except on mine, they put all three (8/10/10) in one can. Because the hole on the chassis for part#55, that had the 10mfd positive to chassis ground, is empty and has no mounting shadow. So then that 3 part can was replaced with the Solar 20/20/20. All makes sense, now. Is this "Welcome to the world of undocumented factory changes"?
RE: Philco 18 changes - Ron Ramirez - 01-10-2013
DKinYORKpa Wrote:Except on mine, they put all three (8/10/10) in one can.
No, they didn't - not at the factory, anyway. There are - or, should I say, were - two aluminum electrolytic cans held on top of the chassis by a metal strap, bracket and screw. These are capacitors (53) and (54).
An under-chassis view will help:
[Image: http://i326.photobucket.com/albums/k420/mrphilco/Phorum%20Stuff/18_under1_zps859c3ddd.jpg]
(53) was 8 uF, 400 WVDC (6706).
(54) was 8 uF, 450 WVDC (30-2025).
(55) was 10 uF, 50 WVDC (30-2003).
Notice also capacitor (40), mounted at the left side of the drawing? It was 1 uF, 1 uF and 2 uF, all 300 WVDC (30-2029).
DKinYORKpa Wrote:Because the hole on the chassis for part#55, that had the 10mfd positive to chassis ground, is empty and has no mounting shadow.
Refer to the drawing above. In early production of the 18, capacitor (55) is separate and mounted off to the right, under the power transformer.
Later in production of the 18 - November 15, 1933 to be exact - Philco combined capacitors (53) and (55) in one package, eliminating the separate (55). Your set has no sign of ever having a (55) mounted on the chassis because it was built on or after 11/15/1933.
Now, look at the drawing below and notice the change.
[Image: http://i326.photobucket.com/albums/k420/mrphilco/Phorum%20Stuff/18_under2_zps7f9e05d8.jpg]
The new combination (53) and (55) is Part No. 30-2045, and contains a single 8 uF @ 450 WVDC and a single 10 uF, 50 WVDC.
DKinYORKpa Wrote:So then that 3 part can was replaced with the Solar 20/20/20.
No, Philco did not install a 20/20/20 Solar cap at the factory. They installed part no. 30-2029 (1/1/2 uF) as shown in the drawings above - part (40).
What some repairman did after the set left the factory cannot be explained by factory documentation. What I have given you are the facts on how Philco originally installed the electrolytics. You have to take this information, compare it to the current condition of your set, and repair accordingly.
RE: Philco 18 changes - DKinYORKpa - 01-10-2013
OK, thanks, I follow that. I knew that the Solar was not factory, though. Why is that 2nd layout not in my paperwork from Chuck? It would have cleared things up immediately.
RE: Philco 18 changes - Ron Ramirez - 01-10-2013
DKinYORKpa Wrote:Why is that 2nd layout not in my paperwork from Chuck?
Because it did not exist until I created it in Paint Shop Pro, to try and help you out. 8)
RE: Philco 18 changes - DKinYORKpa - 01-10-2013
Quote:Because it did not exist until I created it in Paint Shop Pro, to try and help you out
You know I just went out to my shop and took a closer look and you are absolutely right! The piece of sheet metal on the top of the chassis that was folded up straight in the air for those cans is neatly sawed off! This was to make a little room for the Solar can to be attached and screwed to the chassis. How could I have ever doubted you 
?
RE: Philco 18 changes - Ron Ramirez - 01-10-2013
DKinYORKpa Wrote:How could I have ever doubted you
Don't listen to those guys on the other forum who pretend that I, and this website, do not exist.
RE: Philco 18 changes - TA Forbes - 01-10-2013
The Doctor of Philcology strikes again!
