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You likely have an open fuse on the G board.
 

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Yes. I just removed the PS5001 fuse to find out it had blown...again.

So I replaced it and now I confirmed I have -22v across the coils and also at the CN5004 pin #4. IC has been removed .

So basically the IC I had in there was malfunctioning and blew that ps5001 5a fuse again???

I thought if the IC shorted and blew a fuse that it wouldnt short again and blow the fuse again. This is the second time I soldered the IC in. If it was shorted for some reason from the first install then why would the fuse blow again?

:coocoo:....Ok SO....removed old IC's. Checked fuses while still in circuit. They had continuity so i figured they were good. Installed new IC's. Didnt work. Definitely no shorting going on, all connectors hooked up properly, etc. Removed IC's, removed all fuses and all resistors and had blown a 5a fuse on g board with NEW IC's. NOW....If I HAD a blown 5a fuse on "g" board before installing the new IC's, would the blown fuse fry the new IC? Because what I did was remove the new IC's, replace the blown 5a fuse and solder the IC's back in. Well I blew another fuse. BUT...Not both fuses...Just the ps5001 which is for IC 8001. I get +22v and IC8002 heats up and gets correct voltages.

If I would have removed at least one leg of the fuse before installing the NEW IC's I would be able to tell if the IC was bad. Now I dont know if it's still good and something else in the circuit is causing the fuse to blow. :scratch:

I bought another stk chip and am going to install it. This time I know the fuses are all good. If it blows again im gonna throw a :hissyfit:

I am an electrician by trade so troubleshooting is just another day for me.

Thanks if you may have any helpful advice.

T-
 

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Blown fuse again :(...BRAND NEW IC.

Im getting a higher voltage at the coil L5008 (G board) in the -22v circuit for IC 8001. Both sides of the coil, so the coil is good. Im getting - 45.1v. That doesnt seem right...

When I fired it up the IC 8002 got REAL hot. IC 8001 is the BRAND NEW IC I replaced. Thats the ps5001 fuse that keeps blowing.

Connector CN 8013 "D" board has everything but the -22v. Theres no way the IC is blowing the fuse. But it did blow the fuse when i put the IC in. Im thinking its gotta do with something in a circuit on the "D" board. Before the IC was soldered I got - 22v no problem at both boards. CN 5004(g) and cn8013(d).

What else is there? I dont see anything else on the circuit. Resistor R8122 and R8127 are solid wires. :dontknow:

Heres a quote i found....

Hi,
+/-22V come from G board by CN5004 pin4 and pin6 then enters in D board by CN8013 pin4 and pin6 and supplied to IC8001 and IC8002 (convergence output chips)
Reason of missing -20 volts could be D5002, L5008 and PS5001 on G board and above said connectors on G and D boards. Unplug connectors and replug back in to refresh connections.
Did you replaced convergence output chips in tv?
Let me know your findings to find out any further reason/ solution.
Thanks.

So another question is would the D5002 bridge rectifier blow that 5a fuse? Im gonna get to the bottom of this if it kills me...lol.
 

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Discussion Starter · #64 ·
Hi T,

Sorry to be so slow, just been busy here and I kinda forgot about ya!

I'm not following . . . if you don't have anything connected to CN5004 then do you have the -22v? If not then it's probably pico fuse PS5001 just to the left of the connector.

If you do but when you hook the board up and you lose it then yeah, I would think a bad chip could cause that as the pico fuses in the G board frequently go out when the STK chips go bad so a bad STK must be able to cause a big drain on those circuits. It would suck to desolder them again, but maybe it's not a bad idea to see if you have power without the STK in circuit

Again, did you buy quality STK chips or fleaBay, etc. bargain chips? Voice of experience here . . . bargain chips usually aren't a bargain.

Keep us posted, we're rooting for ya!

Steve
 

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When fuses blow it is because there is something drawing too much current downline. In this case it is almost certainly the IC failing. The reasons these fail include bad solder connections, cheap parts, bridged connections, bad convergence generator, bad convergence yoke, or one of the power supply rails missing or noisy.
 

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Thanks!

I will remove the IC's again and do some tests.

Is there a way to adjust the dc offset if my readings are out of spec? Dont see that in the service manual. Need an oscilloscope???

Also what would cause the dc offset values to change? Messing with the convergence before replacing the IC's perhaps? If I switch out the D board and have messed with the convergence, wont this affect the replacement D board? Is there a way to get the convergence back to its "safe" limits if indeed that is the problem or is this unit pretty much headed for the landfill?

T-

ps. take your time and thanks for remembering me! :)

Oh and I found a 51" on Craigslist for 30$ with a crt problem. Maybe the D board is still good? According to your other thread the 51" uses the same D board A-1302-180-A.
What ya think?
 

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Ok I replaced the 5 A fuse and ran some numbers.

All pins on CN5004 on G board are within spec now. Im getting the -22v and its holding. The connector it goes to CN8013 is also within spec. And thats with ALL connectors plugged in. Still not sure what numbers to look for on the DC offset and do I disconnect all the R,G,B connectors on the D board? Which ones are the yokes??? There are a total of 9 on the board. The pin names are printed on the board that goes to the A board for the dc offset. RV,GH,BH ..etc. I am aware of what those intials are.

I still havent found dc offset values in the service manual.

SO....Without the IC's connected, is there a trick to find out whats causing the 5A fuse to blow ? If not and I try new IC's and still blow the 5A fuse and make sure there are no bridges, what can i possibly test for that may be bad? How could I possibly find whats shorting out or if a component is bad with the IC's removed from the circuit??? I guess Id have to check all the IC pads, right???

And Im pretty sure the IC's I have are both good. Ive tried both on the IC8002 side and they will both heat up. Its just the !C8001 circuit Im having issues with.

Ive looked at the D board with a magnifier and I dont see any obvious bridges anywhere, burnt resistors, etc. Ive checked all the resistors in both IC circuits and all are fine.

Like I said when I had the IC8001 connected, I blew a 5A ps5001 fuse and the output of the D5002 bridge rectifier was -45.1v. Should be -22v which it does now without the IC's.


T-

PS. And I have no idea how I am going to test the IC pads to see what kind of voltage is being delivered! The connectors just arent long enough to turn the board over. Can I just leave the CN8013 connector in and the ground as well and then get my readings or do they ALL have to be plugged in to get correct voltages at the IC pads????

Sorry for all the questions but im just trying to think of everything i can here. :bigsmile:
 

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Discussion Starter · #68 ·
Hi T,

It looks like you've been editing your posts. The thing is I tend to only look at the last one or two as I've usually already read the previous ones so when you edit them I usually won't see your corrected/added comments. I'm probably not the only lazy butt so it's probably best to just make a new post.

OK, first, I don't mean to sound rude but you're not answering the question . . . WHERE did you get the STK chips? Trust me here, there is a huge difference between the real versions and the knock off versions of these chips! If you're buying cheap chips the failure rate on them is HUGE and may be contributing to your problem. Buy good chips from the vendors Leonard has recommended in his repair thread. I personally have used Acme in Orlando Florida with great success. By the way, they do offer some Chinese knock offs in certain STK chips that they can no longer source originals for (and the ones in this set may be some of those if I recall correctly). They have researched and tested the knock offs they sell (which is why they will stand behind them with a guarantee) and I've used two sets of them on repairs for friends and I've had zero problems with either set over the last three months or so. Acme is a company that caters to the professional service industry and they care about their reputation so I would opt for originals if they have them, but if they don't I would use their substitutes . . . but they are probably the only company I would buy substitutes from. Like I said, do some research . . . the failure rate on the knock off chips is HUGE. It's not uncommon to get several bad chips in a row - not unusual at all. You're saving so much repairing it yourself that the $20-$30 you save really isn't worth the risk.

OK, I have just a couple minutes . . . if it's a knock off STK it's probably the STK causing the fuse to blow. Remove the STK chips and see if it fires up and doesn't blow the fuse. If so there's most likely your problem. Again, there's a HUGE failure rate in knock off chips. If it still blows you gotta grab the schematic and start from there (after checking your soldering work of course). I've never really had to do that with these sets so Leonard is your man here, but keep in mind he's busy too so he may not have time to walk you through it step by step.

Checking power while it's running can be a challenge. Check the schematic and see if there are any top side componenets you can check for power on. Or, just take some of that fine wire wrapping wire and solder it on to the pc pad and stick it up through the hole where the chip leg would go to create a pig tail you can test.

Also, you're getting the sickness here . . . a FREE tv is driving you nuts! Trust me, it's not the only free one out there! If this one wants to be a pain in the butt just cut bait and grab another one! (I've been guilty of this too though!) Trust me, the success rate on these is high, the chances on you have problems on the next one, especially now that you're uber attentive to your soldering and know how the thing comes apart and goes back together by heart, are very low. The next one of these you do will be a breeze - I promise! I think you mentioned in an earlier post there was a 51" with convergence issues for $30? Probably not a bad price to pay for a fresh start. If you're patient wait a week and offer to take that big heavy thing off their hands so they can avoid the landfill free and you'll probably end up with it for free! I would repair that one by itself and get it running. when it's up and going then move the G and D boards over to the larger set and you should be good go.

Hope that helps, keep us posted.

Steve
 

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Correction, was misinformed by private message... sorry for any inconvenience.

From data gleaned from your posts... have ordered the suggested STK's from my local vendor in Orlando... Acme. Thank you for sharing your expertise regarding the Sony 57 HDTV...
 

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Discussion Starter · #71 ·
Interested in the convergence boards for my kp57ws510 unit? Are yours available or have you sold them on ebay?
I don't really understand your questions.

I'm not interested in your convergence boards unless you simply want to give them away, then I'd pay the shipping. I've been busy so I haven't had any time to play with tvs lately so I'm not really in the parts market.

My repaired G & D boards sold long ago on eBay (and I just got a Christmas note from the lady who bought them and she said they're still running fine! 8-> ).

If you're looking for someone to repair your boards as you're not confident in your de-solder/soldering skills then I would suggest trying to find someone local. If you can't then drop a note back, I may help.

Merry Christmas!

Steve
 

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Yes I also was wondering about locating a "D" convergence board. I do know of a local that will fix it supposedly for about 120$ so I might go that route.

But they are almost impossible to locate. If you do locate anyone who has these "D" board Id be very appreciative to get it on one.

Merry XMAS !
 

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Discussion Starter · #73 ·
Yes I also was wondering about locating a "D" convergence board. I do know of a local that will fix it supposedly for about 120$ so I might go that route.

But they are almost impossible to locate. If you do locate anyone who has these "D" board Id be very appreciative to get it on one.

Merry XMAS !
$120 with parts, if they are good parts and not junk Chinese knock offs, isn't a bad price. Even if you had to buy parts it probably isn't a bad price though really the amount of bench time replacing the ics will take isn't that long.

I would encourage you to get a solder ring pc board at radio shack and a couple ics sockets and practice soldering and desoldering - it's really not that difficult and I'm sure with a little practice you could do it yourself. Still, I understand being short of time and just not having the time to learn the skill.

I would do it for the cost of shipping plus parts but I can't guarantee my work and I don't have a set to test it in (well, I do, but it's our main set and I'm not tearing it apart!), so the local guy is probably your best bet.

Take care, Hope your Christmas went well!

Steve
 

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Sorry, Was misadvised that you had convergence boards available for purchase? No problem... as "Sanyo STK's" are enroute as you had suggested in a recent post, etc.

Wanted to thank you for sharing your expertise regarding this Sony convergence issue.

Thanks again... Semper Fi! ET
 

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Discussion Starter · #75 ·
I'm just a hobbyist. I attempt to fix the tvs and if I can't then I sell off the parts I know are good. They usually sell fast so I don't usually have much on hand.

Glad to see you're giving it a shot - good luck!

Steve
 

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Steve, may I ask if you can describe how you removed the D board? Pictures would work as well.

Thanks,

Shawn
 

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Be very careful removing the high voltage wires. It is not uncommon to break the tabs on them and if you don't reinstall them securely you will get arcing which will destroy components.
 

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Discussion Starter · #79 ·
Hi Shawn, sorry to be slow responding, just been super busy here!

I thought I had pics in the first part of this thread, I'll look in a bit.

It's basically just unhooking the wires - use masking tape to label the wires and I use a sharpie to write on the pcb where I unhook the wire from. I also take a digital pic for EVERY wire I unhook, slow but super helpful for reinstallation! The flip jumpers on the right side of the board just flip up. Look at the service manual to see where the pcb mount screws are at. There's one that likes to hide behind a heat sink over by the flyback transformer.

It's hard to find original chips these days, I've had good luck on three sets now using cheapie chips from Suburban Electronics Wholesale. If you can find originals go for them, if you can't them try the Suburban ones, they must've found a Chinese factory that knows how to make them (Acme used to sell Chinese chips too and theirs worked well also, I'm thinking they were from the same factory).

Don't sweat the hv connectors too much. Just push in and rotate 90 degrees and give a gentle tug. If it disconnected you'll feel it easily, if it didn't just try again. If you break the ears off then PM me as I have a couple extra from sets I scrapped. Really though, just use a gentle tug and you'll be fine.
 

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Hi Shawn, sorry to be slow responding, just been super busy here!

I thought I had pics in the first part of this thread, I'll look in a bit.

It's basically just unhooking the wires - use masking tape to label the wires and I use a sharpie to write on the pcb where I unhook the wire from. I also take a digital pic for EVERY wire I unhook, slow but super helpful for reinstallation! The flip jumpers on the right side of the board just flip up. Look at the service manual to see where the pcb mount screws are at. There's one that likes to hide behind a heat sink over by the flyback transformer.

It's hard to find original chips these days, I've had good luck on three sets now using cheapie chips from Suburban Electronics Wholesale. If you can find originals go for them, if you can't them try the Suburban ones, they must've found a Chinese factory that knows how to make them (Acme used to sell Chinese chips too and theirs worked well also, I'm thinking they were from the same factory).

Don't sweat the hv connectors too much. Just push in and rotate 90 degrees and give a gentle tug. If it disconnected you'll feel it easily, if it didn't just try again. If you break the ears off then PM me as I have a couple extra from sets I scrapped. Really though, just use a gentle tug and you'll be fine.
Huge thanks for the tips Steve. I got the D and G boards replaced and now I have to work with manual convergence. When I got to the screen for convergence I see red, blue, and green crosses in 3's. I have the service manual but it only talks about seeing yellow and white. Did I do something wrong? My TV picture looks like I need 3-D glasses to watch it properly. I knew I would have to go through this phase before things were finished but I'm hoping to squeeze some info out of you ...... LOL

Thanks,

Shawn
 
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