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D-Rock3
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Jul 17, 2009, 2:51 AM

Post #26 of 100 (6623 views)
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Re: [Ron.M] Im in desperate need of help [In reply to]	Can't Post

Im not a bit unconfortable doing the required task just a bit unclear on how. In my line of work we even build power supplies for PCs for the navy to use on their ships. That means 12v @ 50A! I realize the flyback is rated for tons of voltage somewhere around 3Kv if my reading serves me right. I also realize that there are alot of other high voltage components around the board too.

My question to you us what do you mean by measuring "secondary voltages". My apologies for not being as informed as I should to do the required task but like I mentioned earlier, I am a PC tech, not a TV tech.

D-Rock3
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Jul 17, 2009, 2:53 AM

Post #27 of 100 (6621 views)
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Re: [D-Rock3] Im in desperate need of help [In reply to]	Can't Post

OR i could take a picture of the things you would like for me to voltage test and you can edit the image to show me exactly where you would like for me to probe.

D-Rock3
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Jul 17, 2009, 9:25 PM

Post #28 of 100 (6612 views)
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Ya know I didnt even think to look at the sticker for the chassis number. Its an ITC222A

Heres a pic of the sticker.

http://i50.photobucket.com/albums/f311/dancingcorndog3/SANY0049.jpg

Ron.M
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Jul 17, 2009, 11:51 PM

Post #29 of 100 (6608 views)
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D-Rock3;....
1st:In reply:...

Quote

I realize the flyback is rated for tons of voltage somewhere around 3Kv if my reading serves me right.

You're missing a zero there....The flyback generates about 30,000 volts (aka:30 KV) & can knock you on your @$$!!...To say the least!!!

Quote

My question to you us what do you mean by measuring "secondary voltages". I also realize that there are alot of other high voltage components around the board too.

Yes there are other dangerous areas to watch out for...
How much do you know about basic electronics???
Have you had ANY electronics training????
Do you FULLY understand electronic (TV) schematics???

Quote

I am a PC tech, not a TV tech.

"PC";..Does that stand for Personal Computer ,Printed Circuit,or ????
Please elaborate for this old fart....What exactly do you do???Thanks...

Quote

That might be why the schematic you have and what I have in front of me are different.

What exactly do you have in front of you????
Is it a "Service Manual" or just a schematic???

Quote

OR i could take a picture of the things you would like for me to voltage test and you can edit the image to show me exactly where you would like for me to probe.

Good idea,it "may" work....Hold off for now...

PLEASE answer ALL the questions.... Sly

....& post them....OK....
Then I can guide you accordingly....

Later...Ron.M.... Cool

.....
Veteran & Retired TV technician

(This post was edited by Ron.M on Jul 17, 2009, 11:59 PM)

D-Rock3
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Jul 18, 2009, 2:03 AM

Post #30 of 100 (6601 views)
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Re: [Ron.M] Im in desperate need of help [In reply to]	Can't Post

I know my fair share about electronics, I took a college course on principles of electricity, electrical safety, and circuit design as well.

As far as fully understanding TV schematics I have no idea, I dont have a schematic in front of me but I know enough to understand most of the circuits.

As for a PC tech I am a Personal Computer technician but I do work on all sorts of things related to PCs. I build PCs fix PCs, design networks, all sorts of things. Basically if it has anything to do with computing whether it be in a personal or professional aspect I can handle the task. I am certified as an IT Technician and a few of my certifications are A+, Network+, Security+, CCNA, MCSE, MCP, and others of various applications. Part of my job is to routinely trace down problems in PC circuit boards but as i have seen alot of the ICs in PC circuit boards are very different from TV PCBs but some are the same such as volatile RAM, EEPROM, and basic NAND Flash modules.

In front of me I have my PCB from my TV and thats it haha. Im not looking at a service manual or a schematic, Im simply looking at what is on the PCB. I will leave the schematic work up to the professionals such as yourself because I do not FULLY understand all the representations in the TV schematics.

(This post was edited by D-Rock3 on Jul 18, 2009, 2:07 AM)

Ron.M
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Jul 18, 2009, 7:26 PM

Post #31 of 100 (6583 views)
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D-Rock3:.....
THANK you for that VERY informative post... Laugh

....

Quote

My question to you us what do you mean by measuring "secondary voltages".

^^This is what sent up a red flag for me...^^
IF you had "circuit design " you should know this refers to transformers...I believe you do..
You have a "primary" & a secondary windings...
We are going to be measureing secondary voltages...
I'm attaching the file I have for ITC222 in a PM since I can NOT do it here.......
It is NOT exact for your TV ,but close enough for government work...Hahaha...

Quote

I do not FULLY understand all the representations in the TV schematics.

This may be as problem....
If you have ANY problem understanding the schematic,PM or post it asap...OK...
I'll give you further info as we go along , while waiting for the caps...OK....

Later...Ron.M... Cool

....
Veteran & Retired TV technician

D-Rock3
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Jul 20, 2009, 11:58 PM

Post #32 of 100 (6569 views)
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Seems my problem with the reading of the schematic is not what the circuit symbols mean and how to read it but I dont understand the functions of the circuits. I believe I will leave the reading of the schematics for you.

Ron.M
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Jul 21, 2009, 1:00 AM

Post #33 of 100 (6566 views)
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D-Rock3;...OK , NO problem....

Lets get back to this:==>

Quote

If there is anything I can do in the mean time please let me know.

Yeah,if you're ambitious enough...
Lets "SAFELY" Check power supply voltages...
Check ALL secondary voltages off LPO20 Standby transformer...
Do these with the TV OFF...

Then check ALL secondary voltages off LPO50, the run transformer...
Do these with the set ON...
I can NOT stress enough that you use EXTREME CARE when you do this...
There ARE dangerous shock hazards to avoid...
If you are even the slightest bit uncomfortable with this,do NOT do
ANY of this...NO harm , NO foul....

Under NO circumstances go near OR check the voltages on pins 10 & 1 of
LPO50 OR ANY of the components connected to those pins...
Under NO circumstances go near OR check the voltages on pins 1,2,3,4 of
LPO20 OR ANY of the components connected to those pins...
TOO much risk involved...

Check the in & out volts on IP250...Should be 7.2 vdc in & 5 vdc out...
Write down ALL the diode numbers & the readings you get & post them...
Make SURE you have everything connected properly & that the board is in
a SAFE position for you to take the readings...

Once again,I can NOT stress enough to use CARE & COMMON sense
while doing this...

GOOD LUCK....

EDIT:... Are you still having a problem with secondary voltages???
If so ,PM me or post it & I will go into detail....

Quote

I believe I will leave the reading of the schematics for you.

You may need to refer to the schematic to help you locate the part & voltages on the board...

Later...Ron.M.... Cool

.....
Veteran & Retired TV technician

(This post was edited by Ron.M on Jul 21, 2009, 1:14 AM)

Ron.M
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Jul 23, 2009, 1:36 AM

Post #34 of 100 (6551 views)
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D-Rock3;....

Here is a detailed list of what we want to check;....

I have a list of diodes , the transformer pin connections , etc for you to check...
FIRST & FOREMOST:
Unless you can see & reach these diodes from the top side of the board
you will have to somehow prop up the board in a SAFE manner so you can read the voltages I'm requesting you to do....
PLEASE use EXTREME CARE as there ARE some dangerous voltages near where you will be checking... ALL voltages are to be read from Chassis ground & NOT HOT AC ground....

The first one will be LP020....This is the "standby" transformer...
Plug in the TV & do NOT turn it on....

LP020:
Coming off pin #;................Diode#...............Voltage + or -

......................7................DP230................-1 vdc
......................7................DP220................+7.2 vdc
(Coming off DP220 go to IP250 ,Pin 1= 7,2 vdc , Pin 3 = 5 vdc)
......................5................DP241................+5 vdc
......................5................DP240................+3.3 vdc

LP050:..This is the "Run" transformer & at this time turn the TV ON to get the following readings....

(Pins 16/17 may be tied together++>)
.......................16/17.........DP110..................+110 vdc
.......................16/17.........DP112.................+6 vdc
(DP112 is connected to Pin 16/17 thru CP112 & LP113)
.......................14..............DP130..................+16.6
.......................13..............DP135..................-15.8 vdc
.......................18..............DP120..................+20 vdc
.......................19..............DP140..................+10 vdc
.......................22..............DP150..................+6.5 vdc

PLEASE keep in mind that I do NOT have the exact schematic & your TV may not have ALL the diodes listed...If not ,don't worry....
What IS IMPORTANT is that we get readings....

I suggest you print this out so you can have it handy while you take the readings....

That's it for now...Good luck & STAY SAFE!!!

Later....Ron.M.... Cool

.....

Veteran & Retired TV technician

D-Rock3
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Jul 24, 2009, 12:01 AM

Post #35 of 100 (6538 views)
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OK, to start I have replaced the following capacitors and checked for a change, it yeilded no change, the TV still powers off after ~60 seconds.

CP114
CP120
CP150
CP130 (Is the same cap as CP114 & CP120 and had extras)
CP135 (Is the same cap as CP114 & CP120 and had extras)

I checked the voltages on the standby transformer with the TV off from the diodes listed and all came up pretty close to what you expected them to be. Here is what I got off the diodes.

DP230 = -1vdc
DP220 = 7.78vdc
DP240 = 3.45vdc
DP241 = 5vdc
IP250 Pin1 = 7.78vdc
IP250 Pin3 = 5vdc

I checked the voltages on the run transformer with the TV on from the diodes listed. I monitored the voltage on each diode and waited to see if the voltage disappeared when the tv cut off, and all voltages did disappear when the tv cut itself off. These are the voltages I measured..

DP110 = 137.6vdc
DP112 = 6.25vdc
DP130 = 15.38vdc
DP135 = -15.9vdc
DP120 = 20.6vdc
DP140 = 11.73vdc
DP150 = 6.25vdc

Ron.M
Veteran

Jul 24, 2009, 1:59 AM

Post #36 of 100 (6530 views)
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D-Rock3;....

GOOD JOB.... Sly

....

Now we have established that the 2 power supplies ARE working OK....
Now we need to find out what is turning the set off...
This could be due to various reasons...No fear...(YET)...
Now we need to see if the High Voltage circuit is working...
This IS IN AN AREA that you need to use EXTREME CAUTION...
We are going to check the secondary voltages off the flyback transformer....
On my schematic it is labeled as "LL008"...
My schematic is NOT for projection TVs....
SOoo , we may have a problem finding corresponding parts...
IF you have the CORRECT schematic for your TV , by ALL means contact me BEFORE you do ANY of the steps below...OK....
The red wire coming off the top of the flyback carries 30KV & is dangerous if it gets loose....
Do NOT go near it OR ANY of the parts it's connected to....
You will be working on the bottom side of the board as I assume you did previously...
The flyback on MY schematic MAY be similar enough to what you have in your TV....I'm hopeing it is...
Here we go:==>

LL008:Pin#...........Diode#.............."+" or "-"

............12...........DL251...............+16 vdc
............11...........DL231...............+36 vdc
............9.............DL221...............-14 vdc
............6.............DL201...............203 vdc

DL201 probably will not be in your TV as it is used for Video amps on a conventional direct view CRT....
But it may be there for other uses in your TV...
FYI:....Even tho the voltage at DP110 = 137.6vdc is higher than what I show, its NO cause for alarm...
Reason is that my schematic is for a direct view CRT & they are using a variation of the ITC222 for projection TVs...

A couple of questions:
1st:..You said ""the TV still powers off after ~60 seconds"".....
Do you see ANYTHING on the screen BEFORE it turns off???...
Does it turn red,green or blue???
2nd:..What does this mean???... ""CP114 & CP120 --->>and had extras<---""

Later.....Ron.M.... Cool

.....
Veteran & Retired TV technician

(This post was edited by Ron.M on Jul 24, 2009, 2:08 AM)

D-Rock3
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Jul 24, 2009, 2:50 AM

Post #37 of 100 (6521 views)
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IF you know of anywhere to obtain the ITC222A service manual or schematic at a reasonable price I could justify paying for it but I cant seem to find it.

As for your questions..
No the picture on the screen simply turns all black, not red green or blue. When it turns off, the picture goes black instantly, the sound goes out instantly as well when the picture goes out too. The power button light stays on for a few seconds after then goes out. After ~5 seconds the power button light returns and the tv powers on again just as if you had pushed the power button. The TV stays powered on for ~15 seconds before powering off again with the same symptoms as before. Some times the TV will just stay off after the second time it powers off and other times it will power on again 2 or 3 more times. Once it finally stops powering back on, you can wait ~30 seconds and push the power button on either the remote or the TV one time and it will power right back on again and repeat the whole process.

As for the capacitors CP114, CP120, CP130, and CP135 are all the same kind of capacitor. (220uF 35v) I ordered ten of these capacitors because I like having extras. When I went to go and replace CP114, I realized the not only is CP120 the same but CP130 and CP135 are the same also so I just went ahead and replaced them all to eliminate a few variables.

Now for the voltages. These are from the diodes you listed with the TV powered on and using chassis ground.

DL251 = 13.68vdc
DL231 = 41.0vdc
DL221 = -13.68vdc
I did not see a DL201 on the PCB but I only looked for it in the general area of the flyback transformer. <br>

(This post was edited by D-Rock3 on Jul 24, 2009, 2:53 AM)

Ron.M
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Jul 24, 2009, 3:59 AM

Post #38 of 100 (6515 views)
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D-Rock3;...

Once again , GOOD JOB!!!

Those voltages look nominal....OK....
Now the fun begins....
Its 9:00 PM here & I have to get up very early for work tommorrow...
Tommorrow afternoon,I'm goin to do another web search for the right service manual....
In the meantime, lets take a look at the vertical output IC voltages...
That would be IF001...A 7 pin IC attached to a heat sink...
Found this on another website:==>

"""One morning I went to turn on the TV for the kids, and it just kept turning itself off. It worked perfectly until that day.""

Possible solution:==>""unplug 2 ribbon cables they are white then plug them back in should fix it""
Worth a try.....

Later...Ron.M.... Cool

....
Veteran & Retired TV technician

(This post was edited by Ron.M on Jul 24, 2009, 3:59 AM)

D-Rock3
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Jul 24, 2009, 4:18 PM

Post #39 of 100 (6505 views)
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Re: [Ron.M] Im in desperate need of help [In reply to]	Can't Post

Well first I tried removing the ribbon cables and putting them back in. No change.

As I was probing the voltages on IF001 I probeb pins 1,3,5, & 7 first. This is what I got.

1 = 0.517vdc
3 = 40.9vdc
5 = 0.094vdc
7 = 0.523vdc

As I went to probe 2, 4, & 6 I made a mistake. I first probed pin 2 which was 13.6vdc. Then I went to probe pin 4 which was supposed to be -15vdc and I noticed it was -6.32vdc but as I removed the probe I accidentally shorted pin 4 to pin 6. Now pin 4 reads -0.02vdc and pin 6 reads 0.28vdc

If I try to power on the tv the tv will come on for ~3 seconds and power off. It exhibits all the same symptoms as before only the time between power offs has DRAMATICALLY decreased. I may have messed up the vertical output IC but that may have been the problem to start with. This IC is obviously damaged now if it wasnt to start with so my question now is where do I get a replacement for it?

Ron.M
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Jul 25, 2009, 2:12 AM

Post #40 of 100 (6499 views)
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D-Rock3;....

S%&t happens... Pirate

....Sorry to hear that.... Unsure

.....

You said:.==>""This IC is obviously damaged now if it wasnt to start with so my question now is where do I get a replacement for it?"""
I say:..==>It may not have been the "original" problem... But it is now a problem...

Since my schematic is not for your TV , you need to eyeball the IC for a number...
My schematic calls for a TDA8177F that's "IF001"
Post the EXACT number & I will locate a parts supplier for you....
REMOVE the vertical IC....
Check RF009 which comes off pin #3 of the vertical IC...Should be 2.2 ohms....
Check RL231 in the secondary of LL008 (the flyback)...Comes off DL231 from pin #11...Should be 4.7 ohms.....
Check ZL231..That is a fuse & should read "0" ohms..Comes directly off pin #11
Check RL221 in the secondary of LL008...Comes off DL221...Might be about 270 ohms...
Check ZL221 , another fuse & comes directly off pin #9...

Later...Ron.M.... Cool

.....
Veteran & Retired TV technician

(This post was edited by Ron.M on Jul 25, 2009, 2:13 AM)

colala
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Jul 26, 2009, 12:03 PM

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Ron.M
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Jul 26, 2009, 9:00 PM

Post #42 of 100 (6487 views)
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Re: [colala] Im in desperate need of help [In reply to]	Can't Post

colala:...
You ARE a JERK....What the HELL does your post have to do with ANYTHING in a TV Repair forum???...Take your crap & peddle it on eBay or elsewhere!!!................
Veteran & Retired TV technician

D-Rock3
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Jul 28, 2009, 5:06 PM

Post #43 of 100 (6475 views)
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IF001 on my PCB is in fact a TDA8177F
I will resistors and fuses in the next day or so, I have a 9 to 5 job and a two month old son so my days can get rather busy.

D-Rock3
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Jul 31, 2009, 8:06 PM

Post #44 of 100 (6465 views)
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I couldnt find RF009 on my circuit board. This is what I found though.

RL231 = 5 ohms
ZL231 is actually FL231 and it is 0 ohms
RL221 is likely dead at ~1 ohm
ZL221 is actually FL221 which is dead (no continuity)

Im curious as to what resistor I need to replace the RL221 with because it was expected to be around 270 ohms but the color code on the resistor is red, purple, silver, gold, which from what I can work out is .27ohm resistor with 5% tolerance. That surely cant be right.

Now my parts list seems to be consistent of
TDA8177F
RL221
ZL221 (FL221)

(This post was edited by D-Rock3 on Jul 31, 2009, 8:09 PM)

Ron.M
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Aug 1, 2009, 12:22 AM

Post #45 of 100 (6458 views)
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D-Rock3:....

Quote

RL221 is likely dead at ~1 ohm

NOT dead!!..Your meter probably can't read less than 1 ohm....
Chances are , it's good !!

Quote

Im curious as to what resistor I need to replace the RL221 with because it was expected to be around 270 ohms but the color code on the resistor is red, purple, silver, gold, which from what I can work out is .27ohm resistor with 5% tolerance. That surely cant be right.

From my reccollection;.....Red=2.....Purple=7....Silver=10% of 27....Gold=5% Tolerence..
So 2.7 ohms IS right....
On my schematic RL221=270M10....
Not sure what that means....
Go with the .27 ohms..Seems more logical to me...

Quote

Check RF009 which comes off pin #3 of the vertical IC...Should be 2.2 ohms....

Are you SURE it's NOT there????....
There should be a "protect" resistor there of some sort....
It might not be labeled as RF009...
Check & see what comes off Pin #3....

Good Luck...

Later....Ron.M.... Cool

...
Veteran & Retired TV technician

(This post was edited by Ron.M on Aug 1, 2009, 12:28 AM)

D-Rock3
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Aug 1, 2009, 1:39 AM

Post #46 of 100 (6451 views)
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Well indeed you were correct, I traced the plane from pin 3 and found it. It measures 2.4 ohms so that one is okay. Just FL221 and TDA8177F to replace.

D-Rock3
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Aug 3, 2009, 5:43 PM

Post #47 of 100 (6443 views)
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Well in the event of not having no response as to where to order these parts I went ahead and found them myself. I could not find anyone online or local to sell me the PCB rectangle type fuse so I opted to go with a glass pigtail alternative. I got 5 1.25A slow blow pig tails and I also got a TDA8177F from the links below. When they come in I will solder them in and see what happens from there.

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=370228641656&ssPageName=STRK:MEWNX:IT

http://www.goldmine-elec-products.com/prodinfo.asp?number=G16895

D-Rock3
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Aug 9, 2009, 7:49 PM

Post #48 of 100 (6423 views)
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Well the fuses came and I have already soldered one in to replace the blown. The IF001 shipped late so it wont be here until wednesday and I will solder that in then.

D-Rock3
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Aug 16, 2009, 12:18 AM

Post #49 of 100 (6411 views)
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Okay I have the TDA8177F soldered in and it really hasnt made a bit of difference. The tv will power on now but only momentarily and wont stay on long enough to achieve power on the screen. Then the TV will power off and will not regain power again until the AC cord is pulled for some time and re-plugged in.

Ron.M
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Aug 18, 2009, 12:05 AM

Post #50 of 100 (6401 views)
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D-Rock3;....

Sorry about the delayed reply...
For some reason unbeknownst to me I did not recieve the usual email notification that a reply had been made in the thread.....

Back to your TV:....

We need to see if you have ANY deflection at all....
1st we'll check out the vertical....
Then we'll check for High Voltage...
I'll need a couple of pix....
One of the flyback area....
The 2nd is where the Vertical output (Pin # 5 ) connects to the
yoke connector....I need top views of both...

I managed to find a service manual for your TV....Sorry , its NOT free....
It's a downloadable file & costs $15.99...
Here's the link:....

http://www.servicemanuals.net/...74/pos1/results.aspx

IF you decide to get it,do so at your own risk as I have NO
experience with that company....
IF you do ,get the version for R52WH74YX38 <<<(Acts as a DIRECT link) as I think it's the right
one....
If the "YX38" is not on the label on your set,don't worry about it....It's STILL a ITC222A chassis....
IF & when you do,I will need to see it...So that means you will have to email or PM it to me....
As usual , Your call....

Let me know what you decide to do....OK....

Later....Ron.M..... Cool

.....
Veteran & Retired TV technician

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