The microprocessor likely supplies around +5v on pin 62, which will drop to 3.5 through R070. not sure what could be damaged at this point
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Last edited by R_J; 12-06-2024, 06:04 PM. -
So I just remeasured and pin 62 actually has 27 millivolts on it.Comment
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If the microprocessor is now dead for whatever reason, it will not be able to control that port, do you still get a timer/stby led? was any voltage higher than 5vdc supplied to that line?Last edited by R_J; 12-06-2024, 06:13 PM.Comment
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No there is no light at all on the front. No voltage of any kind has been fed into the TV other than via the main connector.
That being said, the past day or two I've been having an issue with the power in this TV flicking on and off ( the relay clicking over and over again ), quite rapidly sometimes and I didn't figure it out until tonight, because I went back to test the two 5v pins on IC001 and there no voltage there. There must be a loose/weird connection in the cable going from A board to G board, because when I was wiggling it the 5v was going on and off the IC001.
Could IC001 have fried because of the 5v line flicking off and on rapidly?
Or is there any other explanation other than IC001 is dead?Comment
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I have a hunch about why IC001 has died. I was thinking about when I did the B+ voltage test with the lightbulb. The B+ line was sitting at about 45v when on, but when I flipped it off it would surge up to about 65v or 70v for some reason. The bulb got significantly brighter.
I noticed the same thing with the 5v standby line when I was trying to figure out what was causing the power to flick off and on. The voltage went up to about 7v each time it turned off.
I looked in the data sheet for IC001 and it's rated up to 5.5v for the Vcc in and so maybe that surge up to 7v over and over fried it.
Does anyone know if replacing IC001 would be as simple as removing the old chip and soldering in a new one of the same model?Comment
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A couple of days ago I finally got my hands on a locally sourced Trinitron and after lugging all 175 LBS home I gave it a good cleaning inside and out. The guy said it had been in a shed for 2 years, but the outside wasn't too bad. The inside was another story and while there was no evidence of mouse, it had certainly been kept in a VERY dirty home.
I cleaned it to an acceptable level of grime, at least clean enough to where nothing would heat up from the dust insulation. I then tried it out and it worked!
I'd say I had it on for about 15 minutes or so and then lugged... -
Hi everyone, I've been troubleshooting my 20" Sony Trinitron (KV-20FV12) CRT after it failed to show a picture. The standby LED is blinking 4 times, which according to the service manual is a failed vertical deflection via the self-diagnostic check during power up.
After getting the TV checked out by a technician and doing research on my own. The most obvious first step was to replace the IC502. I've done so with an exact NOS replacement with no luck. I've read a few suggestions to make sure the 12V supply to pin 2, but that voltage check would seem misleading? It seems if the... -
Hi
Ive got a vintage 2001 sony trinitron flat tube tv
The image is slightly bowed and the left and right sides about 1-2in has fluctuating discoloration that comes and goes if i move or hit tv on sides
See many images attached...
Just windering if this is not fixable or something i can correct without getting too invloved
Im trying to sell the tv
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Buenas mi nombre es carlos me uni al foro porque estoy buscando el schematic de una sony vaio pcg-41217u otras formas de escribirlo son 1p-0117j01-a012 mbx-237 numero de placa revision 1.2 o Sony VPCSB (MBX-237), en fin me gustaria y ayudaria un monton si alguien me puede dar dichi svhematic para hacer las mediciones de una laptop de la mencionada anteriormente(Sony VAIO PCG-41217U) con el fin de repararla dejo de funcionar solo prende el led de la bateria al pulsar el boton de power el disco empiesa a hacer ruido de actividad pero los leds del frontas no reflejan acividad y no enciende la pantalla.... -
This is a CRT I sold a few months ago and it's came back with this weird issue. It's intermittent, but not a thermal fault, or tap sensitive - just completely random. The right side of the picture completely blanks out (picture is not shifted). The on screen display is unaffected though, so not a fault in the line section. Anyone seen anything like before in a CRT?
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