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#31
07-13-2015, 04:09 PM
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Right you are. I shoulda mentioned the tool is plastic (nylon?).
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#32
07-13-2015, 04:58 PM
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hmmm if the sams says to clip a wire across the coil as part of the setup process, then I can presume its not really a horz freq adj as implied on the schematic, That plus the fact that it suddenly stopped working points away from the coil as an issue). a stabilizer is not the same as a freq adjustment coil.
You can try it but if you dont get instant changes the don't go tweeking. I really doubt its going to fix it. Next up, was there any thing else that may have happened before it stopped working correctly? did you try to clean anything or do ANY other work or did you just turn it on and it stopped working? I am presuming you already tried cleaning the pins of the sockets. The most likely error would seem to be in the feed back RC network OR the pot opening up somewhere.
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#33
07-13-2015, 07:30 PM
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Yeah, definitely recheck the reference pulse feedback loop. It goes thru a whole string of components (R81, R82, C54, C62). A break anywhere in the path, like a broken foil trace, would kill the pulse.
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#34
07-13-2015, 09:44 PM
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Thanks for all the good advise, as always!
Well, I did try to adjust both the horizontal drive, and frequency, neither made a difference. There are not many resistors left to replace in the entire set, and I only have about 6 small ceramic caps I could replace in the Horizontal circuit, if by chance one of them may be bad... I will also check the coil to make sure it's soldered well to the board, and no cracks anywhere... and check the hold pot with my meter... I was also thinking, would the horizontal sweep typically have to be re adjusted after replacing caps and resistors and diodes? If so, Sams gives me the procedure... Just not sure how to: "clip a lead across the stabalizer coil"
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#35
07-14-2015, 07:40 AM
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I would do the procedure now. Cant find TP3, must
be at sync sep tube ? Probably the trimmer cap is a coarse adjustment & the coil a fine adjustment. L19 & C59 are a tank so they will oscillate when hit with a pulse. 73 Zeno 
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#36
07-14-2015, 03:59 PM
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Took another look at the chassis today, and found this very thin cloth wire just sitting on top of the Horizontal multi trimmer loose...
The other end is fixed into the board. Is this thread supposed to be connected to the trimmer and possibly broke off???
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#38
07-14-2015, 06:44 PM
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Quote:
If not it may have broke inside the coil. You need to pull the coil & see if you can find the other end then make a new connection to the proper terminal. Get any numbers off the coil while you have it out also. 73 Zeno
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#39
07-14-2015, 08:31 PM
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Quote:
Quote:
I tried both the Hold, and local distance... both had continuity. The Hor.Hold Pot read 7.05 on the end terminals, and when I tested on the center wiper and turned the pot, it went from 0... up to 7.05 with my multimeter set at 20K resistance. I think it's a 10K pot, but unfortunately, even though my sams schematic shows basically the same chassis layout, there are different values, and some caps and resistors are in different places than my set... I wish I could find the exact schematic for my set, but after looking for a long time, this was the closest sams had...
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#40
07-14-2015, 09:40 PM
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just check the coil with ohm meter, should be 45 per sams 1 and 3 I assume 2 and 4 are not used. You can test in circuit. You can check voltages as well, its the plate supply so if its open you would have zero.
Try not to replace any more parts until you cover the easy stuff, like voltage checks and resistance checks (see the sams for pin resistance readings). The biggest mistake that can be made is LOTS of parts getting replaced in a shot gun manner as a method of repair. It can make for a real tough dog. Did you go back and double check all the values of the replaced parts looking for a 10x change? did you spray any cleaning agents (specifically near that trimmer cap)? Last edited by DaveWM; 07-14-2015 at 09:44 PM.
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#41
07-14-2015, 10:06 PM
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Quote:
I will do voltage checks and resistance checks, but I still have to get the right schematic, and it doesn't look like I can find one.... My chassis varies alot in values and placements of capacitors from the schematic I have... Tubes are all the same though!
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#43
07-14-2015, 11:24 PM
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Quote:
and yes, I will always remember not to ever get near trimmer pots with spray cleaner! I don't believe any ran down that far after spraying the Hold pot, but it could have been close! After lot's of searching, I found a write up of my tv model in some old newspaper clippings, it is a Emerson model 2005, or maybe a 2002 or 3... The reason I couldn't find the right schematic, was I needed the letter "C" in front of it. All I had was the number. Now I can order it and have the right one... hard to work blindly!
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#44
07-15-2015, 10:51 AM
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Be careful where you get Sams. You may get a photo copy
or PDF & they both suck to work with. Lots of dealers that can supply an ORIGIONAL for +- $10. Do a WTB here first, you may even get a free one ! 73 Zeno
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#45
07-22-2015, 01:14 PM
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Quote:
Okay, I just did resistance checks of the 6CG7 vert. Oscil. tube: All pins measured pretty close to where they should be, but PIN 7 did not read at all, it's supposed to read 2.3 MEG. Should I investigate the caps & resistors coming off pin 7?
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