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  #31  
Old 11-03-2017, 09:55 AM
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init4fun init4fun is offline
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Quote:
Originally Posted by Crist Rigott View Post
......... If the original wire is lets say 20Kv and I use 40Kv wire, will there be enough "juice" to get through the "extra" insulation of the 30Kv wire to work the 1B3GT?
The voltage breakdown specification of wire refers to it's insulation quality of resisting arcing only , it's the gauge of the wire that determines current carrying ability . If your question centers around whether enough magnetic coupling will exist with the higher value of insulation then I will say I believe you'll be fine , the extra voltage breakdown quality of the wire shouldn't affect the magnetic coupling as long as the gauge of the new wire matches that of the old .
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  #32  
Old 11-03-2017, 10:23 AM
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Quote:
Originally Posted by Crist Rigott View Post
Not at all "upset & Discombobulated". But I'm just trying to control "thread drift". Apology accepted.
Can't help "Thread Drift"... All the Boatanchors I have exhibit it in one way or another.. The EK-07,& my RACAL RA-17 seem to be the least bothered by it..NOT a big deal, as I don't use any of the radios for RTTY work.... I also have a JRC NRD-545 that basically DOESN'T drift.
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  #33  
Old 11-03-2017, 10:57 AM
Crist Rigott Crist Rigott is offline
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Quote:
Originally Posted by init4fun View Post
The voltage breakdown specification of wire refers to it's insulation quality of resisting arcing only , it's the gauge of the wire that determines current carrying ability . If your question centers around whether enough magnetic coupling will exist with the higher value of insulation then I will say I believe you'll be fine , the extra voltage breakdown quality of the wire shouldn't affect the magnetic coupling as long as the gauge of the new wire matches that of the old .
Thanks for the great explanation. Just what I was looking for. I have some 40Kv wire from an old TV with the same conductor size that I'll use.
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  #34  
Old 11-03-2017, 02:23 PM
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Originally Posted by Crist Rigott View Post
Thanks for the great explanation. Just what I was looking for. I have some 40Kv wire from an old TV with the same conductor size that I'll use.

Exactly what I've done in the past in similar TV high voltage cage repairs , that's why I'm confident you'll have no problem with the wire's higher insulation rating .

PS , I may not post all that much , but I've seen your restoration work and you do have great talent with making these old sets look great again
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  #35  
Old 11-03-2017, 03:23 PM
Crist Rigott Crist Rigott is offline
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Originally Posted by init4fun View Post
Exactly what I've done in the past in similar TV high voltage cage repairs , that's why I'm confident you'll have no problem with the wire's higher insulation rating .

PS , I may not post all that much , but I've seen your restoration work and you do have great talent with making these old sets look great again
Thank you for the kind words.
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  #36  
Old 11-03-2017, 07:21 PM
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You fellers who really know how to Work on this stuff are near Deities in my book.. I tried to learn enuf to maybe change out caps & resistors & stuff, but even THAT was beyond my 57 IQ abilities...
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  #37  
Old 11-04-2017, 11:00 AM
Crist Rigott Crist Rigott is offline
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Let's try and get caught up a little at least from the start.

After removing the chassis from the cabinet, I took many of the customary initial pictures of both the main and power supply chassis. I removed the tubes earlier when transporting the TV back home. I then removed the CRT.





I then decided that this thing needs a bath. I went to the local "Quarter" car wash. Yup the local car wash. I used the "Presoak" setting to spray off both chassis on top and on the bottom. Then I used the "Ionised Water" to rinse them off. These settings at the car wash use a lot less pressure and with the wand 3 feet away, the car washing did an amazing good job of cleaning those chassis. Once back home I blew off the excess water with my blow gun set at 40 pounds. Then the chassis went into the oven set at 170 degrees F for several hours. Well worth the effort.



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  #38  
Old 11-04-2017, 11:15 AM
Crist Rigott Crist Rigott is offline
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I then wanted to check the "health" of the chassis by checking all the transformers and coils. All checked good even the nasty looking flyback except the H Hold coil L22 (Sams).

I removed the coil.


I then unwrapped the black tape. Sure enough there was a broken wire.




I was an easy repair to make. I unwound 1 turn and cleaned off the insulation and soldered it back on to the green terminal. If you look closely you can see the original wire underneath the white tape.


I then used some black electrical tape to secure the wire.

Last edited by Crist Rigott; 11-04-2017 at 11:52 AM.
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  #39  
Old 11-04-2017, 11:31 AM
Crist Rigott Crist Rigott is offline
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Then I labeled each component according to Sams 120-13. This is my usual practice. This helps me understand the chassis and the parts locations. When labeling the parts I checked their value against the parts lists. This readily points out what the differences are. Sure enough there were just a few. The Sams had a few typo errors and I also used Riders V6-1 to cross check both the Sams and Riders and the chassis. The biggest difference was R39 (located under L14) is listed as a 33K resistor wired to the 130V bus. This was what the picture shows to be in the Sams. But the chassis has a 75K resistor wired to the 360V bus. The Riders shows a 68K wired to the 360V bus. I'm thinking that perhaps a 68K 1W resistor was in short supply and a 75K was used on the assembly line. Most likely I'll use a 68K resistor.

Also you'll see that I removed several shafts from the front of the chassis to a pot and the tuner to have better access to the components. These will be cleaned before reinstallation.

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  #40  
Old 11-04-2017, 11:49 AM
Crist Rigott Crist Rigott is offline
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I removed the HV cage and disconnected the 4 wires going to the flyback.







After removing the 1B3GT plate wire along with the 6BQ6GT plate wires and the door knob cap and 1B3GT socket I ohmed out the coils. They checked good. I then cleaned up the coils by removing the melted covering by chipping it off and using heat to melt it some. I used a lot of Q-Tips and acetone. I then cleaned off the yellowed cad plating and cleaned up the rest of the assembly.





After cleaning I then baked the assembly at 225 degrees F for several hours. I then used my MG chemical Super Corona Dope and brushed on 4 coats. 1 coat on one side then bake for an hour, the do the other side and bake it again for an hour. This was repeated for 4 coats. The coils are just about filled and 2 or 3 more coats I'll be done. Stay tuned for the results.

Last edited by Crist Rigott; 11-04-2017 at 12:27 PM.
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  #41  
Old 11-04-2017, 01:39 PM
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Looking good!

I like the fact that you label the parts... I actually used one of your underchassis pictures when working on a set (7inch Philco?) . It was much clearer than the Sams photo, and in color, which helps, as well! Thanks!

jr
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  #42  
Old 11-04-2017, 02:04 PM
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Those are nice clean Chassis.
Mine was a rusty mess.

I have used a water hose on one of my TV chassis and it did no damage.
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  #43  
Old 11-04-2017, 02:04 PM
Crist Rigott Crist Rigott is offline
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Here are the Hi-Res docs for this project.
Once the click opens up the file, click on the "Open" tab in the upper right. Click on Adobe Acrobat Reader and then when it opens up you then can save it as like any pdf. Note: very large files.

Schematic:
https://www.dropbox.com/s/imuvrxrdk4...matic.pdf?dl=0

Resistors, Inductors, and Capacitors location:
https://www.dropbox.com/s/e977okir2e...ation.pdf?dl=0

Sams 120-13
https://www.dropbox.com/s/xwcrok7re1...20-13.pdf?dl=0
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  #44  
Old 11-04-2017, 09:48 PM
Crist Rigott Crist Rigott is offline
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Quote:
Originally Posted by jr_tech View Post
Looking good!

I like the fact that you label the parts... I actually used one of your underchassis pictures when working on a set (7inch Philco?) . It was much clearer than the Sams photo, and in color, which helps, as well! Thanks!

jr
Now that's a great idea! You're welcome.
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  #45  
Old 11-06-2017, 11:21 PM
Crist Rigott Crist Rigott is offline
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I finished applying the Super Corona Dope to the fly back tonight. After the last coat, I baked it for several more hours. Here is what I'm going with:







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