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  #31  
Old 01-21-2019, 12:00 PM
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Gleb Gleb is offline
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As seen from the layout, the resistors are connected in parallel with a paper capacitor of a pretty good value (.047uF), so they don't seem like a plate load; rather a sort of B+ divider, damper or bleeder.
You ought to check the schematic diagram to make it clear.
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Last edited by Gleb; 01-21-2019 at 12:05 PM.
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  #32  
Old 01-21-2019, 12:30 PM
dieseljeep dieseljeep is offline
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Quote:
Originally Posted by Crist Rigott View Post
Mostly. This chassis is proving out just like most of them. About 2/3 are clearly out of tolerance, 1/6 are just in tolerance, and the final 1/6 are within tolerance. So having 5/6 of the resistors out of or just with in tolerance, I change them all. The last thing I want to do is go back in and change a resistor that's causing problems in the future. Another thing, my 1W resistors cost a whooping 4 cents each from Mouser. Why take the chance with a 65 year old resistor?
Some of those resistors look a little tired.
BTW, what procedure do you use to remove all the old leads and solder from the terminal strips? On occasion, I use a desoldering iron like used on PC boards.
As usual, amazing work!
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  #33  
Old 01-23-2019, 11:16 AM
Crist Rigott Crist Rigott is offline
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Guys, here is the schematic of those 3 resistors. R131,R132, R133. Looks like I could use a wire wound resistor there...right?

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  #34  
Old 01-23-2019, 11:21 AM
Crist Rigott Crist Rigott is offline
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Quote:
Originally Posted by dieseljeep View Post
Some of those resistors look a little tired.
BTW, what procedure do you use to remove all the old leads and solder from the terminal strips? On occasion, I use a desoldering iron like used on PC boards.
As usual, amazing work!
I usually clip the component free leaving about 1/4 to 3/8 inch on the terminal strip. I then use solder wick to get as much solder off. Then I remove the old leads and again solder wick for final solder clean up. Then using a cut down acid brush, I brush with some acetone to clean off the old resin and make the terminal nice and clean. Then on to installing the new components.
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  #35  
Old 01-23-2019, 02:11 PM
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Quote:
Originally Posted by Crist Rigott View Post
Looks like I could use a wire wound resistor there
Yes you can use any type there; it's just a current limiter for the 2nd grid of the horizontal output tube (V23). It seems that three usual carbon resistors were simply cheaper than a single wirewound one.
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  #36  
Old 01-24-2019, 10:21 AM
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I agree that a wire wound should be OK there. Seems odd the way they have the other side of C123 connected to the cathode instead of ground, as if there was some AC signal to be transferred from one to the other.
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  #37  
Old 01-24-2019, 10:32 PM
Crist Rigott Crist Rigott is offline
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I installed the wire wound.
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  #38  
Old 01-24-2019, 10:38 PM
Crist Rigott Crist Rigott is offline
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While I was on the same side as the Candohm, it was reworked with 3 25W chassis mounted resistors and I used some 2W resistors to "Trim" them to the correct values. All within 1.2 ohms or less than specified.





I then continued working my way through the chassis. I reworked the interlock, V23 and surrounding area.



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  #39  
Old 01-25-2019, 05:46 PM
Crist Rigott Crist Rigott is offline
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Another section completed. This section had some repair work done to it before I got to it.



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  #40  
Old 01-26-2019, 10:36 PM
Crist Rigott Crist Rigott is offline
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Reworked V18 the Sync Amp and Syns Sep. This pretty much completes the Vertical section. Tomorrow I'll move downward through the chassis to the Horiz. section.



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  #41  
Old 01-27-2019, 05:34 PM
Crist Rigott Crist Rigott is offline
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Moving down to V21. The Horiz. AFC section. Next up V22 the Horiz. Osc.



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  #42  
Old 01-27-2019, 10:40 PM
Crist Rigott Crist Rigott is offline
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Finished V22 tube the H. Osc.



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  #43  
Old 01-27-2019, 10:45 PM
Crist Rigott Crist Rigott is offline
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If you look at the lower terminal on the terminal strip in the picture above you'll should see that I replaced the single conductor shielded wire. I used some 20awg wire I had from when I wired aircraft avionics. Good stuff. The reason I replaced it was the center insulator was breaking down and crumbling away, thus creating a possible short between it and the shield. The same thing with the Phono input wire. This will get replaced also.



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  #44  
Old 01-28-2019, 09:07 PM
Crist Rigott Crist Rigott is offline
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I completed tube V9, V10, and V11. Video Amp, Video Output, and Noise Inverter.



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  #45  
Old 01-30-2019, 12:09 AM
Crist Rigott Crist Rigott is offline
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V13 and V14. 1st and 2nd Sound IF done.



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