Videokarma.org TV - Video - Vintage Television & Radio Forums

Videokarma.org TV - Video - Vintage Television & Radio Forums (http://www.videokarma.org/index.php)
-   Solid State CRT Televisions (http://www.videokarma.org/forumdisplay.php?f=184)
-   -   Sony Trinitron kv1925R find (http://www.videokarma.org/showthread.php?t=274479)

Popester 11-23-2021 10:01 PM

From what I recollect Sony flybacks were pretty reliable but occasionally they would fail. The HV block that had red epoxy would crack and then arc to ground are what seemed to fail more often than a flyback. That set looks like it would be new enough to have HV shutdown circuitry on it.

liammc00 11-25-2021 10:16 AM

This is what happened after I fixed a mistake in the power supply that I made. I plugged the set in and turned TV on the TV ran for a couple of seconds then the casting on side of the flyback cracked an smoke came pouring out of it I immediately unpuged the set. Once it stoped smoking I saw were the flyback blew brown gunck out. I did check bottom of the flyback and insulation has zreo cracks. I have replaced the flyback and set powered on and is kinda working I get a picture but it's very bright and the britness control has no effect nore dose contrast(picture control) on the picture. When the tube is warming up you can see the on screen display but once at full britness you can't. I believe the screen control needs to be adjusted but I'm not sure. I have never worked on Sony before nore have I ever replaced a flyback. I also messed up the tunner some how. I get no reception at all but I believe it was a mistake I made I think I have fixed it but I will no once I test the set.

zeno 11-25-2021 06:48 PM

G-2 usually abt 450 volts.If its high it gives your problem.
If G-2 control is on the FBT check for an unsoldered pin
under it.
If G-2 control on CRT socket check the high ohm resistors (over 1 meg )
on socket.

If G-2 OK check the 3 cathodes of CRT ( KR, KB & KG) Should be in range of abt 120-140 VDC. If very low thats the problem. Report back.

73 Zeno:smoke:
LFOD !

liammc00 11-25-2021 08:23 PM

I turned on the tv after fixing the tuner and it is hooked up to a VCR so you get a blue screen. Ok here is the result the I get a blue picture from the VCR and the TV's screen display. The picture is washed out and the britness control has very little affect. I would check the G-2 voltage but I'm afraid I might blow up my meter I only have a multi meter and it's max is 600v. The G-2 can be 375-900v

zeno 11-26-2021 03:21 PM

The 200V line to CRT important. Its also the low end of the G-2.
Check first.

liammc00 11-26-2021 10:31 PM

1 Attachment(s)
Got the TV working and now I'm going to joy one of my favorite tv shows which is Talespin. Thanks for all that help

liammc00 03-30-2022 10:12 PM

The tv still works but do to my lack of equipment and knowledge. The tv is out of adjustment do to me not doing them very good the first time and I was ok whith the picture until I watched some other sets and noticed things being overly bright on this one. As you now I did work on this set and i did adjust the G-2 or screen control but did it on a VCR blue screen. Also the gray scale needs adjusted the raster is slightly blue tinted. The gray scale was out of adjustment when I found the set. I don't know how to do G-2 or gray scale adjustments. Before I being I need to track down a color bar generator/pattern generator and have been looking for one those small portable ones. I will work on the tv once I free up my workbench and I will do the adjustments the tv has super sharp picture and very virbrent color for msot people the picture would be more then watchable in its corrent state. I notice it being to brghit so I'm going to fix it and also the f type needs to have the nut put back on its a little hard to watch TV if the connector is in side the TV. Sorry for any grammar errors I didn't have time to prof read. I will fix any errors I find in this replay when I have time to do so.

zeno 04-01-2022 03:17 PM

For overall blue tint.
No signal, just snow. Warm set up 1/2 hr.
Turn DOWN color level control.
Turn down blue drive to make the pix B&W.
If the blue is already turned down turn UP the red & green
a little at a time to get a B&W pix.
Recheck G-2, there can be some interaction.
Due to age you may not make it perfect but have a good compromise.

73 Zeno:smoke:


All times are GMT -5. The time now is 09:39 PM.

Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2026, Jelsoft Enterprises Ltd.
©Copyright 2012 VideoKarma.org, All rights reserved.