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  #331  
Old 01-27-2015, 06:52 PM
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ok heres an update, and this will likely be the end of this silvertone saga. i will post screen shots tomorrow. but now the 12by7 would not shut off , driving to hard, so pin 2 of the blanker tube was at -80 volts and thats good but getting to the video tube it still would not shut down . it turns out that the -80volts used to shut the tube was not showing at pin 2 of the video tube, since this voltage is needed to work the tube via the bright pot it was still to high. so i checked that path and looked good all resistors to from and around still nothing wrong. so i went back to the sams and went over my work, all was good, all but one cap in the b+ , the 140v source, the chassis cap showed on the old cap as 250v 20uf so it is said to put back what was in there in the first place so i did. but i put a 250v 33uf cap since that looked like it would cover it all. but looking at the sams it showed 250v 100uf so this kind of explained why the 140v source was low it seemed that there may not have been enough capacitance to allow all circuits that used the 140volt source to work properly. so all i had was a 450v 150uf cap and thats what i put in place and it seems that half of the 12by7 didnt have the push behind the 140v source, and not having enough to go around. this is my thought because after changing the cap these voltages all fell into place. the sams says pin 2 of the video tube is -5 and its right there now and no drive lines, just the blue faintly because the blue is up alittle high to get a good black&white picture but ill readjust that tomorrow befor i post the screen shots. as far as the hv , well the adjustment pot is maxed and all i get is just shy of 23kv, not enough but enough to handle white scenes and the kine bias is ccw. good focus and the hv shunt after watching my other silvertone that when the hv is varied the heater would get bright and get dim so now with the bad silvertone at times the heater will do the same when varied but not all the time so something there is still wrong and it just might be a gassy crt and nothing to do about that. so as far as i am concerned the hv regulation is working now but if the crt is infact gassey then ill have to live with that. with the service switch in set up mode the red up and had to increase the bias to see it then the others came up good but i didnt leave the bias up because if i did the hv dipped and bloomed but i was able to raise the bias more this time then befor and this is why i feel the hv is working and that it may be the crt. its not super bright but has a much better picture whites are white and it dont pull in from the side anymore when befor it did. so it looks like this is what im left with, low hv possibly because of the crt because there is nothing else that seems to be pulling the hv down and the shunt tube is not very hot at all. i will try another new shunt tube in the near future just to completely rule that tube out.
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  #332  
Old 01-28-2015, 12:37 PM
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well im probably wrong about alot here since i compaired the rca with sams and rca also uses a 20 uf cap for the 140v source so i checked the cap i had in there it was a 250v 33uf and it tested 32.96 uf, so that cap was good so now i am at a loss as to why the voltages all came into place after changing that cap.
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  #333  
Old 01-29-2015, 03:23 PM
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ok here are a few screen shots it wont be better then this, since this is the best its ever been. even with the hv at just touching 23kv thats all i can get but it is steady.

Last edited by timmy; 01-19-2016 at 11:23 AM.
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  #334  
Old 01-29-2015, 03:31 PM
DaveWM DaveWM is offline
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Put a fork in that, its done.
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  #335  
Old 01-29-2015, 03:36 PM
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timmy timmy is offline
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Quote:
Originally Posted by DaveWM View Post
Put a fork in that, its done.
lol, i thought about putting a bullet in it,lol. hey thanks alot again for all the time trying to figure out what was going on with this set. does it look like its lacking anything ?
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  #336  
Old 01-29-2015, 03:57 PM
DaveWM DaveWM is offline
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looks good to me.
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  #337  
Old 01-29-2015, 05:34 PM
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Hard to complain when they are working that good.

Nice work!
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  #338  
Old 01-29-2015, 06:18 PM
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-WOW- That has a good picture.......

Yah a week ago I might not have wanted to put a bullet in it, But If it did catch fire
I would have suggested just roasting marsh mellows over it..... You and Dave
did a great bunch of work on it ! !

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  #339  
Old 01-30-2015, 10:41 AM
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hey i do thank all you guys for the amount of patients with me and my crazy problems with sets i know i would not have got this working as good as it does now had it not been for everyone here that pitched in and helped me, thanks again. the next one is the maggie but after all of this i may be able to handle this one on my own, ill see, lol,lol...
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  #340  
Old 02-02-2015, 11:41 AM
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well just for the hell of it i took the 1.6 resistor out for the hv adjust pot and replaced it with a 1meg and now i got the proper hv adjustment via the pot bright down 25kv bright up stays steady and now i can set it at close to 30kv if i wanted, works perfect. and dave how you managed to locate that burned cap even not here around the set amazes me even me having this set for close to 4 years and i never knew that bad cap was there. again thanks
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