CurtPalme.com Home Theater Forum

Juvental604 · Joined: 04 Nov 2007 Posts: 40

Hello I recently bought a 6pg from kirk and im playing around with screen size. What I noticed is that the test pattern is quite a bit bigger than the actual screen size that im outputting. Is there a way to increase the screen size closer to the test pattern? The only screen size control I have found so far is amplitude. Is there another control somewhere? I tried looking in the manuals but they arent very helpful.

**AnalogRocks** · Posted: Wed Jan 23, 2008 6:35 am Post subject:

Have you read this? : https://www.curtpalme.com/forum_archived/viewtopic.php@t=4722.html

Curt translates the NEC manual's from technical geek to human speak .

kschmit2 · Posted: Wed Jan 23, 2008 8:40 am Post subject: Re: Nec 6PG screen size

Juvental604 · Joined: 04 Nov 2007 Posts: 40

Ok I remade my image and now the test pattern seems to be about 10% larger than the image . I dont know why but it seemed even bigger before. I noticed that the raster screen size from looking inside the lenses is no where near the edges of the lense. I have the horizontal amplitude on max and its still like this. Is there a way to increase the raster size other than amplitude?

Juvental604 · Joined: 04 Nov 2007 Posts: 40

Never mind I found the h width control on the deflection board diagram.

kschmit2 · Posted: Wed Jan 23, 2008 11:53 am Post subject:

Juvental604 · Joined: 04 Nov 2007 Posts: 40

um you mean having to turn the projector off before turning it right?

dropzone7 · Joined: 12 Jun 2007 Posts: 1069 Location: Charlotte, NC

dbaisey · Posted: Wed Jan 23, 2008 9:06 pm Post subject:

Juvental604,
Might be a good idea if you do some reading first. The H width pot has a specific voltage it has to be set at and with a specific signal or you can blow the deflection board. Don't turn pots ok.

Different signals have different widths depending on signal properties. Doug

Juvental604 · Joined: 04 Nov 2007 Posts: 40

H width control- you can CAREFULLY adjust this control to widen out the raster of the NEC projectors. It’s a good idea to slowly rotate this control while the set is off. If this control is corroded or noisy, it’s possible to blow the deflection board while rotating this control while the set is on. Rotating the control CCW will increase the image width, rotating in a CW direction will shrink the image. Be careful not to overshoot the edges of the tubes as per any CRT installation.

thats all I can find about it under layout and setup tips?
I will read through the manuals again just incase.

dbaisey · Posted: Wed Jan 23, 2008 10:00 pm Post subject:

Juvental604,
Im not sure where the above came from or what manual. For now I would ask Curt for a clarification on your projector model if you bought it from him. It could be a warranty issue. Doug

Look this over. http://www.curtpalme.com/NECPG_MechSetup1.shtm

I did find that comment in the link above the one I posted. What isn't mentioned is the H width pot voltage is set with the video input and freq to 1.8V at max amplitude via the remote to assure the deflection isn't overdriven and fail. This is the master global width for all other RGB signals also. This is listed in the service manual under deflection board set up.

Juvental604 · Joined: 04 Nov 2007 Posts: 40

It was written under layout and setup page . I believe curt wrote those pages? Either way there was no warning about changing to the right voltage. The only warning is about turning it off first. I will email curt to make sure. I also looked through the mechanical setup and nec manual and dont see anything about hwidth.

deronmoped · Joined: 03 Nov 2006 Posts: 1154 Location: San Diego

Awe guys, just let him blow it up, I blew my H-output transistor when I was learning. Lucky for me, that was all that went and after tracking down the part, spending a few bucks, pulling the deflection board and soldering in the new one, I was back up and running. Of course this time, I learned how to set the voltage on the defection board for the H-output transistor, added some fans to the heat sink and did a couple of other things so I would not have the same problem again.

Oh and I almost forgot, that 400 Volts on the deflection board packs a wallop, burned a small hole in my finger Shocked

So go ahead and start messing around Laughing

Deron.

Juvental604 · Joined: 04 Nov 2007 Posts: 40

Is there a guide somewhere for messing with the deflection board? Going to look through all the service manuals now hopefully its there somewhere. Maybe that layout and setup section wording should be changed to prevent that from happening in the future.

Mark_A_W · Posted: Thu Jan 24, 2008 12:54 pm Post subject:

I really wish Curt hadn't written that.

The procedure is:

1. Feed it a Composite Video/S-Video signal and register the signal.

2. Set H-Size to +100% in the menu (make sure Raster is centered first).

3. Stick Multimeter set to 2V DC range on PA Pin 2 on the deflection board (front centre big white plug, middle pin - just jam the red probe in with the wire). Stick the black probe on the chassis for ground.

4. Adjust H-Width pot (NOT H-Size) so multimeter reads +1.80v.

5. Drink Beer.

kschmit2 · Posted: Thu Jan 24, 2008 1:40 pm Post subject:

Mark, you forgot one thing:
it requires the optional V4Dec PWB or a composite to RGBHV converter.

Kai

Mark_A_W · Posted: Thu Jan 24, 2008 1:43 pm Post subject:

Ahh, yeah, sorry.

I've never seen a PG without one to tell you the truth..

dbaisey · Posted: Thu Jan 24, 2008 1:45 pm Post subject:

Juvental604,
Check your PM from yesterday. Marks explanation is right.
This wouldn't be in the owner or install manuals. Its not intended for the end user or something you need to tweak when you get it.
Usually....except if it came from liquidation or some other end user with a dead deflection board.

When you first go to the Faqs page the Disclaimers and Warnings are at the top where no one reads. Under the PG section go to downloads and manuals. There is a service manual for the PG Extra. Under the 'service (field technician) adjustments' its in the DEF PWB section.

When you get more familiar with signals you will see that lower freq signals are much wider then lets say 720P. 1080I is quite a bit wider then 720P. Signal properties we have today are all over the place in porches and resolution.

Curt may have a reason for how he wrote it or may have overlooked it. Doug

If you already adjusted it and don't have a video decoder board let Curt know.

**Curt Palme** · Posted: Thu Jan 24, 2008 3:44 pm Post subject:

The reason I wrote it the way it is, is that I've had dozens of emails saying that 'my width is wrong, and I can't get it big/small enough with the remote control adjustment'.

I tweak those pots almost daily, and have NEVER blown a HOT. I don't know what you guys are doing!

If I didn't show where the width pot was, I'd get lots of emails asking where the pot is located. If I do, I get blamed for blowing an HOT.

There are disclaimers all over the site. SLIGHT tweaking of the width pot won't wreck anything, at least not from what I've seen here. Rapid rotation of the width pot WILL blow stuff up. Doug's sentence above sums it up:

Signal properties we have today are all over the place in porches and resolution.

THAT'S why I showed the location of the H width pot.

dbaisey · Posted: Thu Jan 24, 2008 4:47 pm Post subject:

'Slight' I would use very conservatively. I'm by the book on this procedure for a reason and will not be changing my mind on it anytime soon. I have done way to many warranty Narda's on this board and cracked tubes to know different and I check where the H width pot was set at on the defects that came in.

If your unsure then pull the signal and see where the raster is hitting under a no signal condition or if it defaults back to the video input. You all know I'm pretty conservative but its for a reason. Doug

If you don't have a video decoder you can feed it 15.75 kHz RGB