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  #61  
Old 01-13-2015, 09:53 PM
Bill R Bill R is offline
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I am curious about a few things.
1. where and how are you measuring the regulator current?
2 what is the actual B+Boost voltage? Should be ~1000 - 1200volts if I recall correctly.
3. Have you checked the screen grid resistors in the Horizontal output tube. I think there is a 47 ohm and 13K ohm that if they drift high at voltage cause low High voltage.
One thing that bothers me is that all the controls seem to have to be at one end of their range. This indicates a voltage problem in the B+ or Boost voltage. Possibly not enough drive from the horizontal output stage.
4. Have you checked for leaky caps in the horizontal yoke windings?
The 1.5 meg resistors in the regulator circuit are a matched pair. I would not change them to different values. Since they are 20% they are not out of spec. The key is they should be the same value. Yours are about 7% high, but they are very close to the same value.
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  #62  
Old 01-13-2015, 10:02 PM
DaveWM DaveWM is offline
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Enter ye the 10th circle of hell,

Timmy CTC-12 clone HV regulation.
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  #63  
Old 01-14-2015, 05:02 AM
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Quote:
Originally Posted by timmy View Post
I also double checked all the work i had done by the sams and found none.
Sams can have mistakes, bounce the schematic against an RCA one?
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  #64  
Old 01-14-2015, 09:58 AM
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Quote:
Originally Posted by Username1 View Post
Well, since you got this set with HV problems, and found some wiring mistakes in the
focus area, you should take a few steps to ensure that no problems were introduced
be work done by someone else..... I think you should get, or borrow a good camera,
take pictures of the flyback, the wiring, and under the chassis, post good clear picts, and
some the focus wiring you found and repaired.... There are people here who have
recently worked on and own several of them.....

You might also find that if both of your sets are identical, as far as the chassis goes,
that visual comparison might be a very good idea.... I'm confident the problem can
be found, there are lots of people here who know this chassis inside out....

By the way, which Silvertone is this one.... 63, or 65...? And are they the same.....


.
the silvertone is the pic you see on this page its a 1963. the other ones i have are 65 silvertone and it has a different focus circuit. and besides i have went over this set with the sams hoping to find a mistake by another tech but have yet to find anything other then the focus circuit. and the other is 65 maggie which has a problem as well and that one has the 2v2 circuit. the only thing i can say is when i got the set i changed the focus coil because it had a burn mark so i assumed it was bad and after putting the new one in befor finding the focus miswire the focus was not good at all. so i took it out only to find that one part of the coil had opened so now i couldnt use it anymore and moyers sold me the last one. i then checked the ohms of the old coil and to my surprise up against the sams and it was good but i dont know what the history was to have burned the coil the way that it did but it was still good so i put it back in with a new resistor i think it was 100k because the old one was burned clear apart and its been in there since. even though the ohms check good im not sure if this may be a cause for the hv problem. one other thing i remember is in first getting the set going the horiz hold was all the way to one end so what i had done to correct that was tweeked the coil on the vert board and that fixed that and now it has range left and right to adjust if need be as befor it didnt. sorry for the edits but i did have arcing at the neck somewhere under the yoke when i first got it going but this may hjave been when i took off the reg tube cap to check hv at the time but never did arc again since.

Last edited by timmy; 01-14-2015 at 10:32 AM.
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  #65  
Old 01-14-2015, 10:09 AM
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timmy timmy is offline
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Quote:
Originally Posted by Bill R View Post
I am curious about a few things.
1. where and how are you measuring the regulator current?
2 what is the actual B+Boost voltage? Should be ~1000 - 1200volts if I recall correctly.
3. Have you checked the screen grid resistors in the Horizontal output tube. I think there is a 47 ohm and 13K ohm that if they drift high at voltage cause low High voltage.
One thing that bothers me is that all the controls seem to have to be at one end of their range. This indicates a voltage problem in the B+ or Boost voltage. Possibly not enough drive from the horizontal output stage.
4. Have you checked for leaky caps in the horizontal yoke windings?
The 1.5 meg resistors in the regulator circuit are a matched pair. I would not change them to different values. Since they are 20% they are not out of spec. The key is they should be the same value. Yours are about 7% high, but they are very close to the same value.
i measured the hv current at the jumper location at the 033 cap and i used a fluke dvom and i do trust it works fine. i checked any and all resistors at the base of the hot and they are fine. the sams says the b+ voltages the highest is 400 and 390 volts and other lower ones right off the caps in the PS. the b+ is up because i would not be able to get the voltages at the crt that i get and they would be low but at around 700 volts at the crt seems the b+ is ok. the only thing i did not do is check or change caps in the yoke but i did write it down as something to check. i also had double checked my work with any resistors or caps that i had done which i had changed caps under the chassis only because of this problem and also unsoldered the caps and check them the simple way with a meter and they looked fine thinking maybe i got a bad one or 2. i have a new meter that checks, NF,MFD in caps and also frequency but dont know yet if it goes as high as 15,730.

Last edited by timmy; 01-14-2015 at 10:18 AM.
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  #66  
Old 01-14-2015, 11:14 AM
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Hey, Had a black-out for a few hours this morning... Someone took their pickup a few
quarts of alcohol and went out to get some wood........ Now we got 2 phone poles
on this street cut in half and hangin in the air....

Bill is right about the H-output tube screen voltages, I'm not sure but I think we went over it
before on another thread.... But you better check, the 47ohm, and 13K resistor off pin
4-8 of 6dq5 also suppose to be around 145V there....
My schematic don't have the number, but off the cathode of the damper tube somewhere
should be a test point for B+ Boost, and it should be around 1KV like bill said... Check your
Sams it may have a test point and a number.... 1Kv ~ 1200V ??

Also, since you said you are not a tech, I want to be sure you are aware B+, and B+ Boost
are two different things.... B+ Boost does not come off the power supply section of the tv, it
is part of the voltage from the horiz. output section of the tv..... Generated off the Damper
tube.... They may have a point where they show a test spot, and a Voltage number, so use their
test point....

Did you check or replace the caps on the yoke... C 105 ?? Good one to look at....

.
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Last edited by Username1; 01-14-2015 at 11:26 AM.
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  #67  
Old 01-14-2015, 12:02 PM
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Quote:
Originally Posted by Username1 View Post
Hey, Had a black-out for a few hours this morning... Someone took their pickup a few
quarts of alcohol and went out to get some wood........ Now we got 2 phone poles
on this street cut in half and hangin in the air....

Bill is right about the H-output tube screen voltages, I'm not sure but I think we went over it
before on another thread.... But you better check, the 47ohm, and 13K resistor off pin
4-8 of 6dq5 also suppose to be around 145V there....
My schematic don't have the number, but off the cathode of the damper tube somewhere
should be a test point for B+ Boost, and it should be around 1KV like bill said... Check your
Sams it may have a test point and a number.... 1Kv ~ 1200V ??

Also, since you said you are not a tech, I want to be sure you are aware B+, and B+ Boost
are two different things.... B+ Boost does not come off the power supply section of the tv, it
is part of the voltage from the horiz. output section of the tv..... Generated off the Damper
tube.... They may have a point where they show a test spot, and a Voltage number, so use their
test point....

Did you check or replace the caps on the yoke... C 105 ?? Good one to look at....

.
ok, the 2 resistors of the 6dq5 have been double checked and are ok. the b+ voltages and the boost voltages i know are from different places and i hope the sams shows a test point for the boost voltage. straight b+ i know comes first from the transformer to the diodes then to the caps. i do have alot of tv experence with the new garbage, smd and so on. i know this chassis dont have a boost diode so ill hope to find a test point at the damper for this boost voltage. i was looking at the rca schematic and c105 is one that is there and ill check that. i also know what the doubler caps do ,lol,lol so i do understand... and the screen voltage at the hot pins 4-8 142 volts and pins 1-5 -56
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  #68  
Old 01-14-2015, 12:12 PM
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timmy timmy is offline
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those 2 resistors are 100 ohm and a 47 ohm at the hot , i think i replaced the 100 ohm after getting the set and recapping as i went over this and found that resistor drifted very little and probably didnt even have to change it. just checked the sams it shows pin 2-7 385 volts pin 9 is the one with the hv and it says do not measure. im showing only a 720 v boost source but that dont tell it all.

Last edited by timmy; 01-14-2015 at 12:23 PM.
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  #69  
Old 01-14-2015, 12:31 PM
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This pic shows B+ Boost, where it's made, but not necessarily where
to measure it.....

And the screen grid resistors.

.
Attached Images
File Type: jpg some-horiz-ctc-11-crap.jpg (99.5 KB, 11 views)
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  #70  
Old 01-14-2015, 12:39 PM
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timmy timmy is offline
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Quote:
Originally Posted by Username1 View Post
This pic shows B+ Boost, where it's made, but not necessarily where
to measure it.....

And the screen grid resistors.

.
ok yes i have the same here but this sams is alittle different by the numbers your 3 is my 9 but same location. ok the 13k 7 watt i probably checked that one already but i will again. so now ill have to find out where to test this boost voltage because i believe i hit that spot already by accident and burned another fluke dvom out so i dont want to do that again.
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  #71  
Old 01-14-2015, 12:50 PM
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NO - be careful, there are very high voltage spikes there ! !

.
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  #72  
Old 01-14-2015, 12:52 PM
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my mistake there is no c105 in the yoke the sams i have dont show it nor does the rca schematic but shows it in the color board as a disc cap. the yoke appears to have c 123 caps
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  #73  
Old 01-14-2015, 12:59 PM
DaveWM DaveWM is offline
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horz pos pot wired right, not open?
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  #74  
Old 01-14-2015, 02:45 PM
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horiz pot new and wired, came with the fly.
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  #75  
Old 01-14-2015, 03:02 PM
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I don't know for sure on your set, but on CTC-15 clones I have the boost supplies the high voltage side of the CRT screen/G2 potentiometers, and IIRC the vertical linearity control pot.

On my Silvertone CTC-15 clone there was an SS boost diode that was bad when I repaired my set. Your set may be the same or different so take this with a grain of salt.
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