Tested the hv block again and am satisfied it is good. Found the neon bulb and watched carefully as TV powered up; there was no flash-not even a glow. There was a clicking sound that reminded me of a relay opening. Still the same on the CRT glow, cut off, and 8 blinks. Next, I will remove the D board, find the HOT and test it. My gut tells me it is the flyback transformer. Again, thanks for your help and I'll report back with my progress.
Yep, sounds like a problem with the flyback but remember - that could be because the flyback is bad or it could be because it's not being properly driven by the HOT, from what I gather the HOT goes out a little more often than the flyback does so it's definitely worth checking the HOT, especially since you can test it with rudimentary tools and you can't test the flyback easily.
I'll be interested in what you find with the HOT. The readings on the HOT don't have to be exactly the same, just roughly the same so don't sweat it if they don't match exactly. You're basically looking for conducting or not conducting, not really the degree of either if that makes sense.
Got the D-Board out. I've been looking for the HOT Q8043 with no luck. Could it be the Q8038 that I am looking for? The transitor is stamped with 1MB12-140. It is mounted on a heat sink with a screw and paste. The heat sink is one of the taller ones with fins. In the picture you posted, it is the first tall heat sink vertically above the flyback transformer. It is mounted perpendicular to the flyback. The schematic shows it connecting to the T8005.
I can't find the Q8043 on the schematic or the board.
Hi Joey, I'm a bit pressed for time but I re-read the last part of this thread quickly - I've worked on WS510 units and your working on a WS500. They are similar but there may be some differences in part numbers and stuff.
Here are some pics showing the HOT on it's heatsink, a bottom shot showing how it feeds the flyback, and a shot of the part number (but again, yours very well may be different).
BTW, this is a scrap board I literally dug out of a dumpster so hopefully yours is in better shape!
Thanks so much! I appreciate your time. This is exactly the part I was trying to describe. On my board it is Q8038. From all your previous descriptions, I reasoned that this must be the transistor. Will computer cpu heat sink paste be adequate when I replace it? I will test out the transistor and let you know my results!
At first I downloaded the -510 manual but it didn't match up with some of what I was seeing. I had to search a while in the manual section of techlore, but I found it. Below is the link.
OK. I have the HOT desoldered. Now which of the leads are the base, emitter, and collector? Could you describe them in terms of the picture above as attached to the heat sink, Left - Center - Right.
Went to radio shack tonight and bought a digital mm with diode testing function. I also examined some of their transistors. Their diagram identified the leads from left to right as Base, Collector, and Emitter. So I proceeded with that assumption in testing the HOT.
I put the mm on diode testing function and ALL my combinations read .0F. The directions for the multimeter said this means (a) the connection is open or (b) the multimeter cannot read this diode because the voltage is more than 1.2v.
I don't know if this means it is good or bad or if the meter just can't read it.
Sorry for the delay this evening, we had company so I haven't gotten to my email till just now.
I believe you found your problem! 8->
Yes, according to the spec sheet it's Base Collector Emitter (Google is your friend here).
I've tested a couple of these and my Fluke meter on diode test has always been able to test them. Though your set and the scrap board I have don't use the same HOT I pulled mine and tested it and it tested fine also, so if you followed the earlier posted testing directions and it tests bad then I'd believe it and say it's bad!
I haven't trouble shot this far back on these sets (the lone Sony HV problem I had turned out to be bad hv block). I know the Panasonic I worked on usually had a bad capacitor that caused the HOT to go bad but I dunno if that's an issue on these sets or not. I'll see if I can dig anything up. I'll also take a look at your schematics and see if the circuit looks similar to the Panasonic I worked on.
I'll get back with ya shortly, in the mean time I'd suggest trying to locate one of those HOTs!
Thanks so much for walking me through this. My experience is limited to occasionally swapping boards on LCD TV's -- pretty tame stuff. However, when my projection tv went out, I hadn't the first clue where to start. This thread and your advice specifically has led me to possible solution. It will probably be a week or more before I post back. Thanks so much for your help and I will give you the final resolution.
Glad I could help! There's usually some more experienced techs hanging around here so I'm surprised none of them has jumped in. I'm just a hobbyist so I'm not overly experienced so I hope I've led you in the right direction!
Please do post back how this turns out for ya! I'm really curious! I think you have a very good shot at it though. It appears to me the HOT is shot and since it's not driving the flyback that's why you're getting the hv error.
This is Joey again. I got the HOT today and replaced it, but with no success. I think the mm I have will not read this particular transistor because I tested the new one before I installed it with the same results - .0F on all combinations. Installed and the TV gives me the same 8 blink error. I guess the new HOT could be bad also, but it was brand new OEM. What do you think? Try to swap out the flyback transformer? Entire D boards are also available, but they are a bit pricey.
That sucks! I'm with you - I think the meter isn't able to check the transistor as though the new part could be bad I think the odds of that are low.
Yeah, a flyback would probably be my next choice. Be aware a brand new Sony flyback may not come with the HV leads and removing the old ones from the old flyback may not be an option - in the one attempt I made I couldn't get them out of the flyback, so if you order a new Sony see if the hv leads are part of the deal or if you need to order them separately.
If buying an aftermarket flyback they may say the leads are attached but in the one I recently purchased for a Panasonic project the leads were attached but there were no ends on them (it was an Asti brand). Removing and transfering the focus block end over was easy but the one for the focus block wasn't. It's crimped onto the end and was difficult to get off (though in the end I did get it off and transferred over). When I contacted the place I bought it from (Acme in Orlando Florida) they replied that the connectors don't come on them and they don't carry them nor know where to get them from - they said to transfer the old ones over. Just something to keep mind - an aftermarket one may not be a bargain if you booger up the hv connector and can't get another one!
Changing a flyback isn't hard - the Radio Shack desoldering iron with the bulb attached to it should do it for you.
Steve,
Tested the hv block again and am satisfied it is good. Found the neon bulb and watched carefully as TV powered up; there was no flash-not even a glow. There was a clicking sound that reminded me of a relay opening. Still the same on the CRT glow, cut off, and 8 blinks. Next, I will remove the D board, find the HOT and test it. My gut tells me it is the flyback transformer. Again, thanks for your help and I'll report back with my progress.
Joey
Hi Joey,
Yep, sounds like a problem with the flyback but remember - that could be because the flyback is bad or it could be because it's not being properly driven by the HOT, from what I gather the HOT goes out a little more often than the flyback does so it's definitely worth checking the HOT, especially since you can test it with rudimentary tools and you can't test the flyback easily.
I'll be interested in what you find with the HOT. The readings on the HOT don't have to be exactly the same, just roughly the same so don't sweat it if they don't match exactly. You're basically looking for conducting or not conducting, not really the degree of either if that makes sense.
Good luck - thanks for keeping us posted!
Steve
Steve,
Got the D-Board out. I've been looking for the HOT Q8043 with no luck. Could it be the Q8038 that I am looking for? The transitor is stamped with 1MB12-140. It is mounted on a heat sink with a screw and paste. The heat sink is one of the taller ones with fins. In the picture you posted, it is the first tall heat sink vertically above the flyback transformer. It is mounted perpendicular to the flyback. The schematic shows it connecting to the T8005.
I can't find the Q8043 on the schematic or the board.
Joey
Hi Joey, I'm a bit pressed for time but I re-read the last part of this thread quickly - I've worked on WS510 units and your working on a WS500. They are similar but there may be some differences in part numbers and stuff.
Here are some pics showing the HOT on it's heatsink, a bottom shot showing how it feeds the flyback, and a shot of the part number (but again, yours very well may be different).
BTW, this is a scrap board I literally dug out of a dumpster so hopefully yours is in better shape!
Hope this helps!
Steve
Steve,
Thanks so much! I appreciate your time. This is exactly the part I was trying to describe. On my board it is Q8038. From all your previous descriptions, I reasoned that this must be the transistor. Will computer cpu heat sink paste be adequate when I replace it? I will test out the transistor and let you know my results!
Thanks again!
Joey
Hi Joey, Your welcome!
Yes, the computer heatsink grease will work fine, in fact probably better than the original.
If you found a freebie service manual please post a link for me and I'll grab it when I have more time.
Have fun! (yeah, I find this kinda stuff fun!)
Steve
Steve,
At first I downloaded the -510 manual but it didn't match up with some of what I was seeing. I had to search a while in the manual section of techlore, but I found it. Below is the link.
http://www.techlore.com/download/23110/Sony-KP-51-57-65-WS500/
BTW. I do find it fun and if I get my TV back that is all the better!
Thanks again,
Joey
Steve,
OK. I have the HOT desoldered. Now which of the leads are the base, emitter, and collector? Could you describe them in terms of the picture above as attached to the heat sink, Left - Center - Right.
Thanks, Joey
Steve,
Went to radio shack tonight and bought a digital mm with diode testing function. I also examined some of their transistors. Their diagram identified the leads from left to right as Base, Collector, and Emitter. So I proceeded with that assumption in testing the HOT.
I put the mm on diode testing function and ALL my combinations read .0F. The directions for the multimeter said this means (a) the connection is open or (b) the multimeter cannot read this diode because the voltage is more than 1.2v.
I don't know if this means it is good or bad or if the meter just can't read it.
What is your advice?
Joey
Hi Joey,
Sorry for the delay this evening, we had company so I haven't gotten to my email till just now.
I believe you found your problem! 8->
Yes, according to the spec sheet it's Base Collector Emitter (Google is your friend here).
I've tested a couple of these and my Fluke meter on diode test has always been able to test them. Though your set and the scrap board I have don't use the same HOT I pulled mine and tested it and it tested fine also, so if you followed the earlier posted testing directions and it tests bad then I'd believe it and say it's bad!
I haven't trouble shot this far back on these sets (the lone Sony HV problem I had turned out to be bad hv block). I know the Panasonic I worked on usually had a bad capacitor that caused the HOT to go bad but I dunno if that's an issue on these sets or not. I'll see if I can dig anything up. I'll also take a look at your schematics and see if the circuit looks similar to the Panasonic I worked on.
I'll get back with ya shortly, in the mean time I'd suggest trying to locate one of those HOTs!
TTYL,
Steve
Hi Joey,
OK, took a quick look around the internut and there doesn't seem to be a cap causing a problem with the HOT in these sets.
I'd replace the HOT and see what ya get, it's about a $25 guess but with it testing bad I'd say it's an educated guess with a good chance of success.
TTYL,
Steve
Steve,
Thanks so much for walking me through this. My experience is limited to occasionally swapping boards on LCD TV's -- pretty tame stuff. However, when my projection tv went out, I hadn't the first clue where to start. This thread and your advice specifically has led me to possible solution. It will probably be a week or more before I post back. Thanks so much for your help and I will give you the final resolution.
Joey
Hi Joey,
Glad I could help! There's usually some more experienced techs hanging around here so I'm surprised none of them has jumped in. I'm just a hobbyist so I'm not overly experienced so I hope I've led you in the right direction!
Please do post back how this turns out for ya! I'm really curious! I think you have a very good shot at it though. It appears to me the HOT is shot and since it's not driving the flyback that's why you're getting the hv error.
Take care, good luck - it's been fun!
Steve
Hey Steve,
This is Joey again. I got the HOT today and replaced it, but with no success. I think the mm I have will not read this particular transistor because I tested the new one before I installed it with the same results - .0F on all combinations. Installed and the TV gives me the same 8 blink error. I guess the new HOT could be bad also, but it was brand new OEM. What do you think? Try to swap out the flyback transformer? Entire D boards are also available, but they are a bit pricey.
Joey
Hi Joey,
That sucks! I'm with you - I think the meter isn't able to check the transistor as though the new part could be bad I think the odds of that are low.
Yeah, a flyback would probably be my next choice. Be aware a brand new Sony flyback may not come with the HV leads and removing the old ones from the old flyback may not be an option - in the one attempt I made I couldn't get them out of the flyback, so if you order a new Sony see if the hv leads are part of the deal or if you need to order them separately.
If buying an aftermarket flyback they may say the leads are attached but in the one I recently purchased for a Panasonic project the leads were attached but there were no ends on them (it was an Asti brand). Removing and transfering the focus block end over was easy but the one for the focus block wasn't. It's crimped onto the end and was difficult to get off (though in the end I did get it off and transferred over). When I contacted the place I bought it from (Acme in Orlando Florida) they replied that the connectors don't come on them and they don't carry them nor know where to get them from - they said to transfer the old ones over. Just something to keep mind - an aftermarket one may not be a bargain if you booger up the hv connector and can't get another one!
Changing a flyback isn't hard - the Radio Shack desoldering iron with the bulb attached to it should do it for you.
Good luck, keep us posted!
Steve
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