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I have the BC band aligned as good as I can get it. A tad off on the higher freq's but not to bad.
As far as the SW band goes it is a bit off.
I followed the instructions and get 15MHz dialed in but then when I go down to 10MHz to dial in WWV it actual sits around 10.2-10.3MHz
Is this normal?
Do these things never line up as good as we'd like?
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You Know. Aligning a radio is more than just getting the stations lined up with the dial. Afteran 'alignment" the stations should come in clearer, etc not just on the dial mark.
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I just had same thing happen on my 42-1012 see thread. Found that the Mica Caps around the Osc tube were way off in value. After replacement radio worked and aligned perfect. Also if you get same stations on 2 different frequencies about 1 Mhz apart (image) replacing the mica caps take care of that too.
Skip...
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I guess I'd better go find your thread and look it over.
I am getting that same behavior.
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I had the Caps on hand. Normally you do not have to replace Mica Caps. But looks like these old radios some if not all of the caps drift. Do you have a capacitor meter? easier to check caps around your Osc tube then trying to replace all of them.. Mine were way out of spec..
Skip...
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Looks like she'll be heading back to the bench
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Looking into the mica's now and they don't seem to match up w/ my schematic.
Example: (13) says it's supposed to be a 325 but I read it as a 23 (red, orange, blk???), (4) supposed to be 250 I read it as 600 (blue, blk, bwn)
I also see a resistor (12) on the schematic that is not there. Well its not where it shows in the drawing.
Getting confused :\
http://www.nostalgiaair.org/PagesByModel...013487.pdf
ETA: I need to double check things. I must be looking at things wrong.
(This post was last modified: 05-11-2015, 09:37 PM by Edisla.)
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You need to measure the Caps using the Capacitor tester. The mica Caps read a little different depending on if they use 3 dots or 6 dots. Plus it hard to tell the colors on them since they are over 70 years old.
SKip..
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Ok here is what I see comparing schem to actual parts
Schem / actual part
(4) 250uuF / 600uuF (BL,BK,BN)
(5) 360uuF / 046uuF (BK,Y, BL)
(10) 10uuF / 10uuf (BN, BK, BK)
(12) 680ohm / 1k and found it tucked behind and right on the Osc. coil terminals
(13) 325uuF / 32uuF (BK, O, R)
(16) 300uuF / 300uuF (O, BK, BN)
(20) 250uuF \ 600uuF (BL,BK,BN)
(24) 250uuF / 250uuF (R, BK, BN)
From what it looks like these appear to be original from what it looks like anyway. (5) and (13) I'm not 100% on, hard to get to and values of what I am getting from the color codes seem odd???
(This post was last modified: 05-11-2015, 10:58 PM by Edisla.)
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From what I can tell the two important ones to focus on for SW alignment are (5) and (13).
My meter is reading 360 for (5) and 370 for (13)
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Most of the Philcos I have worked on seemed to have some nonstandard color code on the mica caps. Other manufacturers micas seem to use the standard code. But it seems like Philco had some other color code on them.
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Have you made any progress? Another way to bring in the alignment is to put a small value cap across the tuning cap to give it more range.. That will not take care of the signals appearing on frequencies approx 1 Mhz apart, it will just allow you to get the frequency and dial aligned.
Skip...
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Following the instructions the best I can get is 10.2MHz on the dial for 10MHz and 15MHz on the dial for 15Mhz.
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That is pretty good, actually. You may not get any better than that.
--
Ron Ramirez
Ferdinand IN
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Well if that is expected then I'm going to call it.
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