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  #16  
Old 01-07-2018, 10:30 AM
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decojoe67 decojoe67 is offline
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Continued success with the resto. That is one of the best of the small early post-war 7" sets. I was watching mine the other day and they perform so well. This one was from the son of the original owner, from the original house and never stored away! The picture, as usual, looks more washed-out than it really is:
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  #17  
Old 01-07-2018, 11:34 PM
Crist Rigott Crist Rigott is offline
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Quote:
Originally Posted by mr_rye89 View Post
Very cool set! I've been after a tabletop set like that for a while. Those crumbly rubber wires remind me of that Philco radio I restored
I think it is a cool set too! Yeah, the Philco crumbly wires on 38 and 39 radios!
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  #18  
Old 01-07-2018, 11:35 PM
Crist Rigott Crist Rigott is offline
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Quote:
Originally Posted by decojoe67 View Post
Continued success with the resto. That is one of the best of the small early post-war 7" sets. I was watching mine the other day and they perform so well. This one was from the son of the original owner, from the original house and never stored away! The picture, as usual, looks more washed-out than it really is:
Thanks for the kind words. Your set looks awesome!
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  #19  
Old 01-07-2018, 11:48 PM
Crist Rigott Crist Rigott is offline
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An update of my progress. The HV caps came in so I started with the HV section. I replaced all the caps and resistors, and thouroughly cleaned all surfaces. I removed the phenolic board and pots and cleaned them too.





I then installed a fuse holder in the AC line going to the ON/OFF switch. I used an existing holes and just removed the wire from the interlock and folded it back to the fuse holder and installed a new brown wire from the fuse holder to the interlock.



I then installed C1 and wired that.



Then C2 was replaced with a terminal strip and 2 E-Caps. The ground terminal was soldered to the chassis like all ground terminals are. The terminal strip was placed in the same location as the clip was for C2. The wires were then just tacked in place so I could do a power up.

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  #20  
Old 01-08-2018, 07:38 PM
Crist Rigott Crist Rigott is offline
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I'm replacing the components in the Horizontal and Vertical sections right now. I thought that I would include a picture of how I arrange things when I'm doing a section of the chassis.

First thing I do is take some close up pictures of the area. Then using some lined notebook paper and a pencil, I draw out what is connected. For example let's say a tube we'll call V12. I draw a circle and place the key way and 8 dots which represent the terminals. I then draw a resistor going from pin 1 and the other end of the resistor I list where it goes like #3 V13, and so on. I also draw in what ever is connected to that terminal like wires, coils, etc.

Then I clip out the components that I'll be changing out. I lay then next to the chassis then I measure the resistance of the clipped out resistors and record them on my spreadsheet. I then get a new resistor and measure that and again record it on my spreadsheet. I dig out the the new caps too. I placed the new components next to the old ones. I then clean up the terminals and clean them using an acid brush and acetone. I then make any repairs needed to wiring etc.

Then I start to install the new components. It's like building a kit now! After soldering, I again clean the terminals with acetone.

Then take a break.

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  #21  
Old 01-09-2018, 07:53 AM
Crist Rigott Crist Rigott is offline
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The Horizontal and Vertical sections are finished. Today I'll power it up and see my progress.

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  #22  
Old 01-09-2018, 04:05 PM
Crist Rigott Crist Rigott is offline
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I did the audio section today. Here are the before and after pictures.



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  #23  
Old 01-10-2018, 09:41 PM
Crist Rigott Crist Rigott is offline
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Today I worked backward through V9 the Ratio Detector, V8 the sound IF, V7 the Video Amp, V6 the video detector, V5 the 3rd Video IF, and V4 the 2nd Video IF. All that's left is V3 the 1st Video IF and the Tuner.



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  #24  
Old 01-10-2018, 09:53 PM
Crist Rigott Crist Rigott is offline
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BTW, I got a original Sams Photofact for this TV. It's Sams 59-2. I scanned it and sent Steve at ETF a compressed pdf copy that is much better than what's up there now. Looks like Steve did some further compression and the copy isn't all that good.

Never fear. I've uploaded the full resolution pdf in my dropbox. You can enlarged it at least 400X and it is still very readable. Here's the link. Caution large file @16Mb.

https://www.dropbox.com/s/o0f1yge36v...059-2.pdf?dl=0

Last edited by Crist Rigott; 01-10-2018 at 10:01 PM.
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  #25  
Old 01-11-2018, 10:00 AM
Crist Rigott Crist Rigott is offline
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OK, I have a concern that I need cleared up. There are these ceramic capacitors used in this TV, mostly in the IF stages. I call them "Hot Dog" caps because they look like hot dogs. Seeing they are ceramic I haven't paid too much attention to them when I do a recap. On this chassis I'm down to the last tube, tube V3, and decided to check some of these caps because they were already disconnected while I'm replacing the resistors. Well, to my amazement the 5 I checked were well out of tolerance......I think.

According to the the Sams parts list, C12-C16 (the ones I checked) can use Aerovox 1468, Cornell-Dubilier 1W series which both are mica caps. I looked in the 1951 Allied catalog and the C-D mica caps have a tolerance of +/- 20% while there was no tolerance listed in the Allied catalog for the Aerovox caps.

In the picture of the schematic below I have penciled in the readings I get for each capacitor. They are:
C12 - 1623pf
C13 - 1431pf
C14 - 1931pf
C15 - 1707pf
C16 - 1230pf

Should I check all of those hot dog caps and replace them too? I've never replaced those before because I've always thought they were good. Now I'm not so sure.




Last edited by Crist Rigott; 01-11-2018 at 10:09 AM.
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  #26  
Old 01-11-2018, 12:55 PM
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bandersen bandersen is offline
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Those are ceramic caps used as RF bypass and coupling and very reliable. Probably the most reliable components in vintage electronics. The value is not critical. I would leave them alone.
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  #27  
Old 01-11-2018, 01:12 PM
kvflyer kvflyer is offline
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Also, don't forget that you capacitor checker leads could be adding to the value of these capacitors. They are very low in value. Try separating the leads and measure them again.

As Bob mentioned, I would be inclined to leave them alone.
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  #28  
Old 01-12-2018, 05:09 PM
Crist Rigott Crist Rigott is offline
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OK guys I left them alone. I appreciate your feedback.
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  #29  
Old 01-12-2018, 05:38 PM
Crist Rigott Crist Rigott is offline
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Guys, I've got another problem! Some background first.
all through this recap and recarb, when I powered up the TV, the picture seemed weak. I had to twiddle the Contrast, Brightness, V. Hold, and H. Hold controls just right to get a picture. The picture was always a bit unstable. It would flicker and when I adjusted the Contrast control, the V. Hold would need readjusting. Though I think this might be a nature of the beast. As I went through the recap, the picture got just a little bit better. Then when I was finished with all the recapping, the picture was still a bit unstable but the flickering all but stopped.
Then I changed the 8 resistors in the tuner. Now here's my problem. I have very good audio but no video. I have a raster but no video. No amount of twiddling the controls will produce a picture. I even tried another CRT with the same results. I replaced the 6AU6 Video Amp tube and even changed 6AL5 Video Detector tube and still no joy. I checked the 2 coils (Sams L14 and L15) or ( Riders, Wallace, and Admiral L9 and L10) and they checked good for continuity.
Could this problem be caused by something in the tuner? I figured that with good audio, the tuner was doing its job.
Any ideas as to where to look?
In the meantime, I'll hook video directly to the Video Amp and see what I get.
Thanks for your help.

Here's a link to the Wallace schematic. Thanks to Phil Nelson.

https://www.dropbox.com/s/vtr06fdq1z...opped.jpg?dl=0

Last edited by Crist Rigott; 01-13-2018 at 12:16 AM. Reason: Changed recapped to changed 8 resistors.....
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  #30  
Old 01-12-2018, 06:27 PM
Crist Rigott Crist Rigott is offline
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OK, when I hook the video directly to the Video Amp tube, I get decent video.
Then I went back to the original set up and now I'm getting a very faint picture.

I'm thinking that maybe I need to just do the IF/Video alignment.

Can a problem with the tuner cause this problem? Just wondering.

Last edited by Crist Rigott; 01-12-2018 at 06:33 PM.
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