My first plasma, RCA 42PA30RQ - Sound but no picture

[lookimback]

Re: My first plasma, RCA 42PA30RQ - Sound but no picture

The RCA buffer isn't working either. Can't find a datasheet for the ICs. However, once I remove the two which had burn holes the short between the pads on the regulator went away. I'll post the resistance reading in about a half hour, when I get home. Also, I don't know if the regulator was bad or not because I cracked it while removing it.

[lookimback]

Re: My first plasma, RCA 42PA30RQ - Sound but no picture

With the ICs removed, I get 3.189k ohms between the ground pad and and the pad closest to the diode (right side pin). With the ICs in place it was shorted.

[lookimback]

Re: My first plasma, RCA 42PA30RQ - Sound but no picture

Finally got it working. Ended up replacing the X and Y mains and the Y buffer. Plus I converted it to a Samsung PN42C450B1D.

[Jimmy60]

Re: My first plasma, RCA 42PA30RQ - Sound but no picture

Can I ask a dumb question? When I check voltage coming from the power supply board I only get 3.2 VDC on the two VS check points. Does that indicate I have a power supply problem? Or is this a feed back voltage from the X or Y boards?

Thanks for your help.
Jim

[lookimback]

Re: My first plasma, RCA 42PA30RQ - Sound but no picture

The correct voltage for VS should be around 207v. The panel sticker has the voltages on it. This would be with the PS on. I don't know what it would be when off. Make sure you have your standby voltage present and that you're getting a turn on signal from the main.

[kissmedave]

Re: My first plasma, RCA 42PA30RQ - Sound but no picture

I have the same rca and the same issue sound but no video.
What board i supose to replace?

[tw2005]

Re: My first plasma, RCA 42PA30RQ - Sound but no picture

I have the same rca and the same issue sound but no video.
What board i supose to replace?

Safest way would be to replace the X,Y and Y buffer boards all at once, unless you can work out what's good or bad but a few of us have tried the short cuts and ended up replacing the lot.

The long way can be the cheaper way too, always a chance you put a good board in and it fails again because of the bad one you missed.

I think Xmain is the main problem but can kill the ymain.

I tried repairing the x and ended up blowing the y so i did the 3. The buffer was ok in the end but x & y were definitely shot.

[kissmedave]

Re: My first plasma, RCA 42PA30RQ - Sound but no picture

Tw2005,
Thank you so much, i will replace all 3 like you said.
May you tell me those parts#? I will go ebay look for it.
Thanks

[tw2005]

Re: My first plasma, RCA 42PA30RQ - Sound but no picture

They are on the boards but if you go to Shopjimmy and type in your TV model itwill list the boards. You can find a few revisions like for the buffer but all work.

can't do all the work for you, best way to learn is to figure it out which you will.

http://www.shopjimmy.com/catalogsear...lt/?q=42pa30rq

don't think you'll find a firmware upgrade unless you contact RCA but the Samsungs did but obviously can not be used on this as the main board is not Samsung.

Worth looking around a bit before you buy but pretty cheap really $90, 3 boards and should be working again.

[tw2005]

Re: My first plasma, RCA 42PA30RQ - Sound but no picture

PM sent

[kissmedave]

Re: My first plasma, RCA 42PA30RQ - Sound but no picture

Oh, man!
Thank so much, very cheap man!
I bought y & x to replace it first.
Not sure about y buffer board.

[tw2005]

Re: My first plasma, RCA 42PA30RQ - Sound but no picture

Oh, man!
Thank so much, very cheap man!
I bought y & x to replace it first.
Not sure about y buffer board.

Well, your choice, y buffer may be ok, maybe not. But if it's bad and blows the y and then the X

[kissmedave]

Re: My first plasma, RCA 42PA30RQ - Sound but no picture

OK...I am not sure what is looks like for the y buffer, I need to take the picture in morning.
Earlier you have posted those link for me, there are 3 of y buffer and I am not sure which one to buy.
For the y & x board I had both pictures on my cell phone, not y buffer.
And the links you pm to me are broken, not woking (error 404).
can you tell me what p/n for they buffer?. I go back to main webpage to search for it.
Thanks again tw2005!!!

[tw2005]

Re: My first plasma, RCA 42PA30RQ - Sound but no picture

they're in sequence so 739 would be the last 3 digits. Yeah i posted it then removed it and the site abbreviates it so you got incomplete link.

Sorry about that chief.

Pretty sure all revisions will work, I think there maybe 4, Rev A-D

[kissmedave]

Re: My first plasma, RCA 42PA30RQ - Sound but no picture

I already ordered X &Y on the way, I still looking for y buffer.
I will replace all 3 at same time, will post back later.
Thanks again tw2005!

[kissmedave]

Re: My first plasma, RCA 42PA30RQ - Sound but no picture

Thanks for your pm emailed to me. Will buy one y buffer, and post back after 3 boards are installed.

[kissmedave]

Re: My first plasma, RCA 42PA30RQ - Sound but no picture

I already received X & Y board yesturday, I don't want to try without Y buffer board.
Like you (tw2005)said if the Y buffer bad will blow off the new X & Y board, Y buffer will be here next week for sure, because I ordered a day after X & Y board.
I will update when I receive a new Y buffer board.

[lookimback]

Re: My first plasma, RCA 42PA30RQ - Sound but no picture

If you go to shopjimmy, you can also find part numbers for compatible substitute Y buffers. They may look slightly different, as some have different capacitors and ICs, but they will work. I found the part numbers for a compatible substitute, then I searched eBay for those numbers. Found one for $18.

In my experience with this TV, a bad X or Y main took out the buffer, but a bad buffer did not take out the X or Y mains.

I had to replace all 3. I first tried just the X. The new one shorted instantly. I didn't care because I had already ordered the RJP30E2 and RJH30E2s. My intention was to refurbish them anyway. While waiting on those MOSFETs, I came across another TV with the same parts and broken panel, for $15 delivered to my door. It had a bad buffer, but good X and Y mains. I put them in and then tried both buffers with no luck. The one I ordered on eBay did the trick. When all was said and done, I had a working TV and 2 refurbished and working X mains which I sold on eBay. I came out with a profit and haven't even sold the TV yet. Right now I'm letting a friend's mom use it as a loner while I work on her TV.

[kissmedave]

Re: My first plasma, RCA 42PA30RQ - Sound but no picture

Hi lookimback,
You are good on lcd tv, and I'm not.
This is my first tv broken down, and thank a lot for your explanation.
I have to buy all 3 samsung parts because my Rca built with samsung parts.
Tw2005 PM me for the place to buy it is very good price, I bough 3 samsung parts less than $100.
Thanks both of you for helping me.

[lookimback]

Re: My first plasma, RCA 42PA30RQ - Sound but no picture

Trust me when I say this, you have 4 options for replacing the Y buffer. And they are all made by Samsung.

These are the cheapest of each variation. The LJ92-01739C is the lowest priced and is from the same seller I bought mine from.

LJ92-01739A

LJ92-01739B

LJ92-01739C

LJ92-01739D

All of those are compatible. The only differences are that some use electrolytic capacitors instead of ceramics, and ICs used may be a different brand. So they may look slightly different. But they will all work.