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  #16  
Old 05-09-2017, 09:18 PM
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Quote:
Originally Posted by cluelessgame View Post
Here are the pictures of the antenna as mounted inside the cabinet. It appears that there is some sort of sheath insulator it collapses into. I think there is a little grommet at the top that'll let me take it off and put it on another one.

Looking closer at the UHF tuner it appears something internal has indeed broken as the outer shaft also turns continuously.

Findm-Keepm PM me your info so I can send you postage fare, I'd really appreciate those parts.

I tried injecting a weaker signal and it didn't really help things. checked all the resistors around the Horiz AFC and they all appeared to be in spec. I've also included a pic of the disk cap that looks suspicious. I maybe should emphasize that this issue also affects vertical linearity too, yet all the resistors around the sync separator are in spec as well. speaking of the vertical, I failed to mention previously that the vertical hold pot stem has broken off. luckily its stuck in a position that locks on, but it appears that replacing it will mean i'll have to replace the vert. height and linearity controls too as all three are contained in a housing that clips in. I've toyed with the idea of maybe trying to glue something onto the nub and hope it stays, but I'm not sure what kind of adhesive to use (JB weld?), as well as what to glue to it.
PM me your address - I'll get the antenna and the knobs out to you ASAP. The ceramic cap looks ok - the caps are sprayed with a waxy substance to make them move through the automatic insertion equipment, and the wax can "boil off" if too close to a tube. RCA, in their field service seminars would recommend cleaning all ceramic discs in IFs, Sync and Oscillator circuits with naptha (lighter fluid) to remove the wax. If too much accumulated between the leads, it could affect the value of smaller value capacitors.

Also remember that an engineer specified that cap and it's temperature coefficient for that spot on the board. As to sync, have you replaced any AFC diodes? If not, we always replaced them as a preemptive measure. You can use any 1N914, 1N3064, 1N4148, or similar switching diode. Cheap, and good insurance against a call-back.

As to the vertical hold control, I have many Striptrols, and about 30-40 New-in-package ones for GE. I'll check the part number in my Sams and see if I have one - same story, yours for postage only. I've got two TV shops AND a distributor's GE inventory (all post '65 parts...), so I'm set for specific GE parts. I long ago got rid of the generic stuff - caps, CRTs, resistors, crystals, lamps, fuses and non-GE marked semiconductors...
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  #17  
Old 05-10-2017, 06:55 PM
cluelessgame cluelessgame is offline
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the only diode (read: solid state diode) in this set is the video detector. There is a full-wave rectifier in the A-part of the 8B10 compactron that's labeled as the "Horiz AFC" and it tests pretty strong, and all of the components around it are in spec.
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  #18  
Old 05-11-2017, 09:16 AM
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I'm also sending this shaft to replace the vertical hold shaft - the striptrol (Lin, Ht, Hold) comes apart with the bending of about 6 or 8 tabs, and the broken shaft can be replaced. Centralab, Stackpole and CTS all made them, and there are subtle differences, so the shaft has a 50/50 chance of fitting your striptrol.

Cheers,
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Last edited by Findm-Keepm; 09-29-2017 at 07:39 PM.
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  #19  
Old 05-12-2017, 05:05 PM
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Quote:
Originally Posted by cluelessgame View Post
the only diode (read: solid state diode) in this set is the video detector. There is a full-wave rectifier in the A-part of the 8B10 compactron that's labeled as the "Horiz AFC"
You missed the B+ rectifier diode off the powerline and the UHF tuners also usually had a mixer diode.
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Old 05-12-2017, 06:48 PM
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You missed the B+ rectifier diode off the powerline and the UHF tuners also usually had a mixer diode.
...and you missed the zener......
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  #21  
Old 09-25-2017, 03:33 AM
cluelessgame cluelessgame is offline
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It's been a while since I've updated this thread, thought I'd bring everyone up to speed on things. I changed the lone ceramic/paper-wax capacitor on the HV side. Still getting some horizontal warp on high contrast images (even with a weak signal) and have yet to find its cause. I have not performed an alignment yet, so far it yields visible lines up to 3.0MHz on a multiburst bar sweep pattern. Would an alignment produce a higher response?

Also I've noticed that the HV hum is EXTREMELY LOUD. Is this normal or is the flyback being over driven?

lastly, thank you very much, Findm-Keepm, for the parts! So far I've installed the antenna and the UHF knob, but yet to install the V-hold knob as the "striptrol" is an absolute pain to get into x.x
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