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RCA 52" convergence power supply dead

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jts1957
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Mar 29, 2013, 9:45 PM

Post #26 of 48 (3017 views)
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Re: [HostileHST] RCA 52" convergence power supply dead [In reply to]	Can't Post

Quote

The down side to all of my schems is I can't find squat other than a block diagram with the PSDF board in it.

Having just DL'd one plus their ITC222 PTV training manual - a PSDF schematic is on page 7 of Thomson 29DC850 (for one, I may check out others in days ahead).

-------------------------
Location: Far, Far Away

HostileHST
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Mar 29, 2013, 10:10 PM

Post #27 of 48 (3012 views)
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Re: [jts1957] RCA 52" convergence power supply dead [In reply to]	Can't Post

I found it shortly before your message JTS1975 and sent info to Ron. Thank you though!

Ron.M
Veteran

Mar 29, 2013, 10:13 PM

Post #28 of 48 (3012 views)
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Re: [HostileHST] RCA 52" convergence power supply dead [In reply to]	Can't Post

HostileHST;...

The diode reading is OK...

Here's the deal;....
Upon closer look at the PS/ON issue....
On my Sams schematic is the following circuitry....

In each of those small black boxes is a number that refers to a source voltage supply...
Those 6+ transistors that turn on the power supply are NOT on the same board...

In those boxes are the following sources;...
#51=+15vdc
#72=13 vdc
#74=-15 vdc
#79=3.3 vdc
The problem is that I presumed those voltages all came from the "Convergence power supply"....WRONG !!!!
Source #72 comes from #43 (13 vdc)...
Source #74 comes from #46A (-15 vdc..
Source #79 comes thru several parts & eventually winds up at pin #8 on LL008..
ALL 3 of those supply voltages come from ....wait for it...........

the POWER SUPPLY on the DEFLECTION BOARD !!!!
Now you need to check the fuses on "LL008"
pin #8 , FV90= 400ma amp fuse..
pin #9 , FL221= 1.25 amp fuses...
pin #12 , FL251 =1.25 amp

Have fun with those...
I'll be back later on...
I have some errands to run & will be downloading the manual in the meantime....

Later...Ron.M... Cool

...
Veteran & Retired TV technician

Ron.M
Veteran

Mar 29, 2013, 10:23 PM

Post #29 of 48 (3011 views)
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Re: [jts1957] RCA 52" convergence power supply dead [In reply to]	Can't Post

jts1957;....

Quote

a PSDF schematic is on page 7 of Thomson 29DC850 (for one, I may check out others in days ahead).

29DC850KG was one of the manuals you PMd me with a link to....
I didn't download the manual because I felt that the model number indicates that the manual is for a CRT Direct View TV & may not be what HostileHST has in his TV...
I appreciate your help...

Have a GREAT day & weekend... Sly

....

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

...
Veteran & Retired TV technician

HostileHST
New User

Mar 29, 2013, 11:25 PM

Post #30 of 48 (3005 views)
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Re: [Ron.M] RCA 52" convergence power supply dead [In reply to]	Can't Post

I am not getting any voltages off of those fuses, not before the fuse and not after the fuse. I've checked them probably 3-5 times in and out of circuit, so the fuses are ok, but no voltage reading what so ever.

I am unsure where FV90 is, unless you are referring to FL231.

There is a 8 pin connector on the deflection board, BL500, that goes to BL600 on the PSDF.

Readings where:
1. -13.64
2. shows nothing on meter
3. 1.927 volt
4. shows nothing on meter
5. shows nothing on meter
6. 13.49
7 -8.9 mvolt

Not knowing where to put my negative lead, I put it on the metal jacket of the RF Coax input of the tuner.

I think the schem JTS1975 is describing is the same one I have and that does seem too look like the PSDF I have, at least very close to it.

jts1957
Veteran

Mar 29, 2013, 11:56 PM

Post #31 of 48 (3002 views)
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Re: [HostileHST] RCA 52" convergence power supply dead [In reply to]	Can't Post

Main Training Manual also available here: http://www.techlore.com/...ile/27245/ITC222.pdf

Main training manual has 114 pages / PJTV training manual has 52 pages
Main Training Page 72 (PJTV Training Page 10) has Dead Set Troubleshooting flowcharts.

-------------------------
Location: Far, Far Away

(This post was edited by jts1957 on Mar 30, 2013, 12:23 AM)

Ron.M
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Mar 30, 2013, 12:09 AM

Post #32 of 48 (2997 views)
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Re: [HostileHST] RCA 52" convergence power supply dead [In reply to]	Can't Post

HostileHST;.....

Quote

I am not getting any voltages off of those fuses, not before the fuse and not after the fuse.

You won't....
You should be checking ohms , NOT voltage....
While you're at it , look for DL221 , DL231 & DL251...
Check on the band end of DL231 for +42 vdc...
Check on the band end of DL251 for +13 vdc..
Check on the plain end of DL221 for -15 vdc...
DV90 may not be the problem...
So pass on that one for now...

All we need to do is determine IF LL008 is working...
My guess is that it IS since you said that the TV comes on but the convergence is lousy...
We may be missing one of those supply voltages..

jts1957;....

From what I can tell , he does NOT have a dead set or the 3 times strike out problem...
He has NO convergence...
Right , HostileHST ???..

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

...
Veteran & Retired TV technician

HostileHST
New User

Mar 30, 2013, 12:40 AM

Post #33 of 48 (2991 views)
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Re: [Ron.M] RCA 52" convergence power supply dead [In reply to]	Can't Post

All three fuses are good using the meter set on ohms.

DL221 showed -13.7 vdc
DL231 showed 41 vdc
DL251 showed 13.5 vdc

The tubes light up, I get a picture, no convergence, even the menu is not converging, but ultimately, yes, the TV turns on, tubes light up, shows a picture on the screen, I just can't keep my eyes crossed that many ways no matter how much I tip back one.

HostileHST
New User

Mar 30, 2013, 12:42 AM

Post #34 of 48 (2990 views)
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Re: [Ron.M] RCA 52" convergence power supply dead [In reply to]	Can't Post

Can someone put some light on the "3 strikes out" problem? Is that when we all take turns shooting a gun at the TV?

jts1957
Veteran

Mar 30, 2013, 1:07 AM

Post #35 of 48 (2987 views)
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Re: [HostileHST] RCA 52" convergence power supply dead [In reply to]	Can't Post

A baseball bat may be involved. Smile

-------------------------
Location: Far, Far Away

Ron.M
Veteran

Mar 30, 2013, 1:31 AM

Post #36 of 48 (2982 views)
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Re: [HostileHST] RCA 52" convergence power supply dead [In reply to]	Can't Post

HostileHST;...

Well , all those diode readings are fine.... Unsure

..

This IS really bad timing , but , it's looking like the FET (TP630) has crashed...
ALL the supply voltages are there for the convergence power supply to fire up...

I doubt you'll get one over the weekend...
When you do get it , use care when you handle it as it's static shock sensitive..
post the generic number of the FET & I'll see what I can do for a replacement...

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

...
Veteran & Retired TV technician

HostileHST
New User

Mar 30, 2013, 2:14 AM

Post #37 of 48 (2977 views)
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Re: [Ron.M] RCA 52" convergence power supply dead [In reply to]	Can't Post

Getting the FET might be tricky, I need cash, but if you think it might be the FET, I can always see about getting one sometime next mid month. Very long time for any of us know what happens, but heck, if, just if it fixed it, it's worth the wait, I'm tired of the ol' 32" we have.

Number shown on the FET is:
F3HNK90Z

900 Vdss, .42 Rd, 3A

Would seem if a person could get a 400+ volt FET with the rest being VERY close to the same, and was an N channel FET, it should work. I've done that with normal Transistors with some success.

Ron.M
Veteran

Mar 30, 2013, 2:37 AM

Post #38 of 48 (2971 views)
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Re: [HostileHST] RCA 52" convergence power supply dead [In reply to]	Can't Post

HostileHST;....

Please keep in mind that I said it "looks" like the FET crashed... Unsure

...
I did not say that replacing the FET "will" fix it... Sly

..
I haven't checked around yet (Tomorrow , I will) , but , they can't cost much more than a 2013 Lexus , so I wouldn't worry too much about it... Wink

...
It certainly would be worth a try at this point....
I'm nearly fully bald from pulling my hair out... Wink

...
I'm NOT fond of subbing these types of transistors...
Too many times there were complications...

But , as I've said hundreds of times;...
It's your TV...
It's your money...
It's your call...

I'll let you know what I find out tomorrow...

Have a GREAT evening..... Sly

...

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

...
Veteran & Retired TV technician

HostileHST
New User

Mar 30, 2013, 3:25 AM

Post #39 of 48 (2968 views)
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Re: [Ron.M] RCA 52" convergence power supply dead [In reply to]	Can't Post

That is why I was heavy on the IF, cause I know right now that it MAY not be the problem. Plus I have read several times, that when and IF a mosfet goes bad, to replace the driver as well. So if I am able to get TP630, I would also like to replace the driver so I'm not going bold wondering IF I should got both.

To me, for the last 25 years of this hobby, it's all been hen pecking till you get it right. Some times, we get it right the first time, those are sure nice when that happens.

And yes, my money, my time, my call, my tv, BUT if I never get it fixed, the Fresnel will be used to build a solar cooker, with lots of other good parts to keep around for other projects. So in the end, no loss, I did get the TV for free.

HostileHST
New User

Mar 30, 2013, 3:27 AM

Post #40 of 48 (2966 views)
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Re: [HostileHST] RCA 52" convergence power supply dead [In reply to]	Can't Post

Bold? MMM, yes, sounds much nicer than bald, let's go with that!

jts1957
Veteran

Mar 30, 2013, 3:53 AM

Post #41 of 48 (2963 views)
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Re: [HostileHST] RCA 52" convergence power supply dead [In reply to]	Can't Post

TP630 RCA 259630. If n/a from RCA distributor,
NTE2399 should do it ( STP3N90).

-------------------------
Location: Far, Far Away

HostileHST
New User

Mar 30, 2013, 4:32 PM

Post #42 of 48 (2955 views)
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Re: [jts1957] RCA 52" convergence power supply dead [In reply to]	Can't Post

JTS1975, I downloaded the datasheet on the NTE2399 and though similar, the Vgs is 2vdc min and 4vdc max where the F3HNK90Z is +_30vdc. It would certainly blow the NTE2399 on first turn on of the TV. The rest does look very close though with 1000 volt, 3.1amp and .5ohmRds(on).

It's still good do see folks out there willing to look for substitutes the hard way beings there doesn't appear to be a cross reference for the F3HNK90Z. My cross reference book is from the 90's, I highly doubt anything in it is still in production other than the famous 2N3055 transistor. Ah the good old days when things were much easier to repair and build.

(This post was edited by HostileHST on Mar 30, 2013, 4:34 PM)

HostileHST
New User

Mar 30, 2013, 4:35 PM

Post #43 of 48 (2952 views)
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Re: [HostileHST] RCA 52" convergence power supply dead [In reply to]	Can't Post

Sorry, I keep mis-spelling your name JTS 1 9 5 7, I'll learn eventually.

HostileHST
New User

Mar 30, 2013, 5:16 PM

Post #44 of 48 (2950 views)
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Re: [jts1957] RCA 52" convergence power supply dead [In reply to]	Can't Post

How about this one, it's overkill and a different package, but could work:

STW15NK90Z

Has nearly the same specs other than it's a 15 amp version, TO-247 package with an Rds of .55 ohms

Found that at mouser.com

jts1957
Veteran

Mar 30, 2013, 8:33 PM

Post #45 of 48 (2942 views)
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Re: [HostileHST] RCA 52" convergence power supply dead [In reply to]	Can't Post

Just as long as I GET the extra 18 years ... Cool

-------------------------
Location: Far, Far Away

Ron.M
Veteran

Mar 31, 2013, 6:51 PM

Post #46 of 48 (2924 views)
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Re: [HostileHST] RCA 52" convergence power supply dead [In reply to]	Can't Post

HostileHST;....

Sorry to say that I've had NO luck finding a replacement... Unsure

...
Suitable sub OR the exact one .... Unsure

....
The full generic number for the FET is;...STF3HNK90Z..
You might want to see what that number does for your cross checking...

IF appropiate;....Happy Easter...
IF not ....Happy Wester.... Wink

...

GOOD LUCK !!!...

Later...Ron.M... Cool

...
Veteran & Retired TV technician

HostileHST
New User

Apr 4, 2013, 6:46 PM

Post #47 of 48 (2875 views)
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Re: [Ron.M] RCA 52" convergence power supply dead [In reply to]	Can't Post

I found 2 new STF9NK60Z mosfets in my parts bin. I looked it up and it has these specs:

600 Vdss
.95 Ohm Rds (on)
7 amp

It looks like a real close match to the original but can someone, hopefully in laymen terms, explain the Rds (on) and the importance of the ohms not being the same as .42 of the original?

I'll google, but not sure how far I'll get trying to get the specific information I am after.

HostileHST
New User

Apr 27, 2013, 7:51 PM

Post #48 of 48 (2847 views)
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Re: [HostileHST] RCA 52" convergence power supply dead [In reply to]	Can't Post

I tried one of the STF9NK60Z's from my parts bin and got 58 vdc at DP675. I powered the tv off, turned it back on and no voltage there. Upside, or at least it's how I am seeing it, I did get voltage at least once! Sadly because the TV's screen is up against a wall with no mirror to easily see the screen, I couldn't see if the convergence was working during the breef moment of having voltage. GRR

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