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  #61  
Old 12-15-2015, 11:16 AM
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Kevin Kuehn Kevin Kuehn is offline
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Something does not look right there. Am I correct that the cement Dale says 10 ohms on it? Compare your wiring to what Riders shows. I added the resistance values in red.




Last edited by Kevin Kuehn; 12-15-2015 at 11:30 AM.
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  #62  
Old 12-15-2015, 11:18 AM
old_coot88 old_coot88 is offline
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Deleted. Posted too soon

Last edited by old_coot88; 12-15-2015 at 11:21 AM.
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  #63  
Old 12-15-2015, 11:27 AM
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If my eyes are not deceiving me, and that is a 10 ohm cement Dale resistor that's replacing the 6750 ohm candohm section, then there's one heck of a load on the B+. But I'm having a hard time seeing the connections.
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  #64  
Old 12-15-2015, 11:43 AM
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No, the 10 ohm is replacing the 12 ohm R240, which was open on the candohm. But the ground is totally disconnected from the second pin of the 6750 ohm candohm section, and I relocated it to the Dale resistor rather than jumpering it across. The hell??? Before it all made sense to me, now I'm looking at this wondering what the devil I did here.....
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  #65  
Old 12-15-2015, 11:50 AM
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And why would I use such a big resistor?? Okay, time to start from scratch on this candohm replacement. Now, none of it looks right.
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  #66  
Old 12-15-2015, 11:52 AM
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Well what's confusing me, is that Riders only shows two resistors in that Candohm, but Sams lists sections A,B,C. Yet your picture seems to show a separate resistor for the 12 ohm?
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  #67  
Old 12-15-2015, 11:57 AM
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Is there by chance a 12 ohm resistor between the two inside terminals of the Candohm, and the left side is no longer connected to ground?

Last edited by Kevin Kuehn; 12-15-2015 at 12:03 PM.
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  #68  
Old 12-15-2015, 12:11 PM
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That's what is getting me, too. I think that's where my confusion lied. Using the Sams, I'm assuming that between the 2nd and 3rd pins of the candohm, I should read 12 ohms, and I'm reading it open. I stuck a 10 ohm monster resistor in there for some reason.

It appears that at worst, all I did was miss a ground on the 6750 ohm section of the candohm. But aren't the two inside terminals of the candohm supposed to read 12 ohms as represented in the Riders diagram above, or no?
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  #69  
Old 12-15-2015, 12:19 PM
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Quote:
Originally Posted by Kamakiri View Post
But aren't the two inside terminals of the candohm supposed to read 12 ohms as represented in the Riders diagram above, or no?
No, the Riders diagram shows only two resistors inside the Candohm, and then R240 is the 12 ohm resistor, which one end is connected to the 3rd terminal from the left, and it's other end heads over to chassis ground(what looks like a spade lug), along with the GND wire that grounds the 2nd terminal of the Candohm.


What is the resistor looking component that my red arrow is pointing to, is it a 12 ohm resistor, because I thought that was the same component that Riders is calling R240.
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  #70  
Old 12-15-2015, 12:25 PM
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That explains the whole damn thing. Got it. You're right, that IS the 12 ohm.

So, all I have to do is get rid of that 10 ohm resistor, and hook the ground back up to the 6750 ohm side of the candohm and I should be in business. It checked fine before, but now is reading about 14K ohm. I might have one here, but the Sams isn't specific about the wattage.
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  #71  
Old 12-15-2015, 12:29 PM
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From what I see in the RCA service manual is the candohm is two separate resistors and R240 is a separate 12 ohm resistor going to ground so yes it can go between the two middle terminals.

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  #72  
Old 12-15-2015, 12:35 PM
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Riders says 3.2 watts on the 6750 ohmer.

By having the one end of the 6750 ohm resistor not grounded, you introduced higher than normal voltages to some circuits(haven't looked at which yet). That may explain why some circuits were pulling more than their normal load.

Last edited by Kevin Kuehn; 12-15-2015 at 12:43 PM.
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  #73  
Old 12-15-2015, 12:39 PM
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My next question- is the green wire end of the 12 ohm resistor connected to ground, so now you have both ends grounded? In other words, did you inadvertently connect the end to chassis ground that was suppose to be up on the 3 terminal from the left of the Candohm?
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  #74  
Old 12-15-2015, 12:54 PM
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Is it possible the other green wire you have going to the left end terminal of the Candohm, is also grounded, and that should be on the right end of the 6750 ohm section? It would make some sense that those two green wires disappear to a ground lug under the chassis. Sorry about so many details, but it's just a little confusing in that chimney.
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  #75  
Old 12-15-2015, 01:00 PM
old_coot88 old_coot88 is offline
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At this point, with the chassis still in fault mode, I would put an ohmmeter on the main B+ rail, to ground. A good place to find the B+ rail is the width coil or the top of filter caps C3A/C2B. (with the set off, of course.) Connect the positive lead to the B+ rail, negative lead to ground. What reading does it settle into after the initial charge-up spike?
Does it stop hard at a few K ohms, or drift up into the fractional-megohm range?

Last edited by old_coot88; 12-15-2015 at 03:57 PM.
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