#1
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Anyone know whats causing this?
Only the very right side has light. Its not HV, have plenty, Not a tube, not the yoke either. I suspect caps but not sure. Has sound. I'm sure something stupidly simple. RCA CTC-16XL Chassis.
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"It's a mad mad mad mad world" !! http://www.youtube.com/user/mwstaton64?feature=mhee |
#2
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how is the crt?
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#3
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A little weak on the red. Blue and green are very good. If I turn the contrast all the way to one side(low), I get a full raster but looks like hum bars going up the screen and the sides look like waves. It has vertical and horizontal sync. I can display a picture on it. I checked the B+, right on spec and .006V AC measured. Seems pretty clean to me. I suppose it could still be the crt
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"It's a mad mad mad mad world" !! http://www.youtube.com/user/mwstaton64?feature=mhee |
#4
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is there any blue or purple glow coming from inside the neck of the crt? turn the lights off maybe to see it better if its there. horiz output tube good as well as the others?
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#5
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No purple glow. Also would of showed up when I had the tester on it. I'll try another crt and see what it does. All tubes are good. Already tried swapping tubes, no change
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"It's a mad mad mad mad world" !! http://www.youtube.com/user/mwstaton64?feature=mhee |
Audiokarma |
#6
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is the hv at around 23kv? focus voltage?
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#7
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lots of going over and ruling out. how old is the set?
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#8
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HV and focus voltage are right. 1966 RCA CTC-16XL
__________________
"It's a mad mad mad mad world" !! http://www.youtube.com/user/mwstaton64?feature=mhee |
#9
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Hum bars and wavy width says the B+ that supplies the sweep has a lot of hum on it. Suspect your B+ measurements are bogus or you measured the wrong B+ point (maybe later filtered section for other circuits).
Edit - is width varying or just horizontal phase? |
#10
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was any caps replaced in the set as of yet?
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Audiokarma |
#11
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I measured the right part of the B+(400V rail) No caps replaced yet. I get 406V B+(line voltage is 120V) there is that electrolytic in the vertical section that may be bad. I'll get to it later.
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"It's a mad mad mad mad world" !! http://www.youtube.com/user/mwstaton64?feature=mhee |
#12
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horz blanking
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#13
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Also might want to check if the screen grids are at aproximatly the right voltage. I had a boost diode fail on my CTC-16 clone and it droped the screens so low that the CRT would only light for an instant when turning the set off. If your boost diode is going south then it could cause the dimness you are experiencing.
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Tom C. Zenith: The quality stays in EVEN after the name falls off! What I want. --> http://www.videokarma.org/showpost.p...62&postcount=4 |
#14
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Checked the screen grid voltages. All OK.
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"It's a mad mad mad mad world" !! http://www.youtube.com/user/mwstaton64?feature=mhee |
#15
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I recapped the set and also tried another good CRT. Still having the same issues. The hum bar is not as bad as before but still there. Full raster when contrast is all the way down, turn it up then only the right third is visible. The pic seems to roll when I do this but it's hard to tell. Not really sure sure to go from here. I'll start to check voltages at the tubes. Don't know if it's in the video section or hor/vert section.
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"It's a mad mad mad mad world" !! http://www.youtube.com/user/mwstaton64?feature=mhee |
Audiokarma |
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