jpdylon
03-09-2008, 12:06 PM
I remember this being a failure in the power supply - probably a filter. I can't find my service notes and I'm wondering if anyone remembers the value and location of the cap responsible for this symptom?
I'm somewhat disabled from an accident last week and I need to be dead on certain before I take the chassis out... manipulating large things is a pain so I try to avoid it as much as possible.
Thanks in advance.
radiotvnut
03-09-2008, 12:50 PM
There is a 10uf, 315 V (or close to it) cap that is probably bad. I think it's located on the bottom part (power supply) area of the chassis. This cap is in the B+ line to the video output circuit. I've seen it bad many times on the newer System 3 sets. Give me the chassis number for your set and I'll see if I have a Sams and then I can tell you exactly where it's located and it's exact value.
jpdylon
03-09-2008, 08:15 PM
Chassis 25HC45.
There is a 10uf / 300v cap which is part of the multi section filter. That could be it. Does the sams have any information as to what color line that would be? I'll pull the chassis if I have to, but right now I just want to try and trace it out.
zenith2134
03-09-2008, 08:38 PM
In this case I'd just re-cap the video output section. I have seen a few sets of all different ages with a dim side of the screen, and its always either on the video-out board or around it. Caps are cheap enough. Would kinda be a nuisance if its a multi-section though
radiotvnut
03-09-2008, 09:04 PM
If it turns out to be the multi section, I'd replace all the sections at once. There's been several times when I'd change just the bad section just to have another section fail in a week.
kx250rider
03-10-2008, 12:50 PM
H chassis; is that the one with an inline tube and a 9-121-xx socket module? If so, there's an elecrolytic on that board that can cause it. 10 @ 350, or thereabouts.
Charles
jpdylon
03-10-2008, 11:50 PM
I'll double check the module number. It has a delta-gun tube - probably one of the last. I think this one was made around 76-77
EDIT*
This one has the 9-123-01 module on the power supply board of the main chassis. No cap of that value other than in the main filter can
This has the 9-92 vert, 9-89 vid output, 9-90 horizontal, and 9-88 luminance module _if that is of any help =/
I have no service data on this set and I'm somewhat limited in mobility. I'll try to get the chassis out and have a better look. I suspect the section of the filter has gone bad.
radiotvnut
03-11-2008, 01:02 AM
I have a sams on a 19HC45 (19" version of your set) and the 10 uf cap is part of the filter can. There should be approx. 213 VDC on that cap.
jpdylon
03-13-2008, 10:44 AM
Sure enough, the 10uf, 300v section was open. I'm going to replace the filters, and get this thing up and running again.
Thanks for the help as always gentlemen.