CurtPalme.com Home Theater Forum

jbltecnicspro · Joined: 23 Apr 2016 Posts: 512

Good afternoon all,

It's been a wild ride with my G70's. One fixed PA board and three new neckboards in, and I'm ready to calibrate. However, I'm noticing a strange issue with my green tube. I can't perform any electronic focus adjustments on it, save for 2PH and 2PV. The four-pole adjustments don't work, and MG-ALL doesn't work either. Blue and Red focus just fine, but green won't do it. Has anyone experienced this? What could possibly be the issue?

Thanks.

gregstv · Joined: 27 Aug 2007 Posts: 628 Location: Australia

Check all your connectors are in correctly. One for the green focus coil may of come loose or not mated properly.

**Curt Palme** · Posted: Sun Oct 02, 2016 11:24 pm Post subject:

It is possible that the focus output board is bad, which is located under the keypad.

jbltecnicspro · Joined: 23 Apr 2016 Posts: 512

jbltecnicspro · Joined: 23 Apr 2016 Posts: 512

draganm · Joined: 08 Mar 2006 Posts: 8990 Location: Colorado

jbltecnicspro · Joined: 23 Apr 2016 Posts: 512

Yes, I have a spare parts machine.

Actually, I think that the "new" green that I swapped in from the parts projector always had some focus issues. Since my projector is still hanging on the ceiling, and since I will need some people to help me pull it down, what would be the easiest way to diagnose?

This focus output board is underneath the keypad? How hard would it be to get to while mounted on the ceiling?

I guess first thing's first. I'll go under there tonight if I have time and check the cables. If that doesn't fix it then I may try and do a board swap while it's mounted or get a couple of guys to come over and pull the projector and do some parts swapping and testing.

I may end up having to change the CPC magnet out for another one, because I swear the old green tube's focus was able to be manipulated. That said, when I got my PA board back from Curt and the green tube was dim, I was so sure that the problem couldn't be my neck board, but it ended up being the issue. Go figure Very Happy

This stuff isn't all that bad or hard. But damn - if the projectors didn't weigh so much! Very Happy

jbltecnicspro · Joined: 23 Apr 2016 Posts: 512

And ladies and gentlemen... It was the cable. Very Happy

Green is focusing TIGHT now. We're finally ready to roll with the calibration.

jbltecnicspro · Joined: 23 Apr 2016 Posts: 512

Alright, so I've been continuing to get my G70 calibrated. I've hit another, smaller roadblock. My red tube is flairing a bit at the right side of the screen. Optical focus is fine (I can see the phosphor grain) and when I look into the tube face I can see that the flair is on the face.

I've tried adjusting the focus, and while the adjustments are working, they're not doing enough to bring the red tube in as tight as green. This is the "new" red tube - the one with less wear than the old one. The old one, if I recall correctly, was tight as a button. This one? Not so tight.

So what does this mean? I'm pretty sure I don't have a board issue, and what I'm probably staring at is a tube that needs to have its focusing mechanically adjusted. What am I looking at? How hard is it to adjust the magnets?

**Curt Palme** · Posted: Fri Oct 07, 2016 1:32 am Post subject:

If you can see the flair on the tube face through the lens, it will most likely be astig. Man, it's been too long since I've set up a G70, all I do is G90s now, but run through the astig adjustments. are you sure the dot is completely round in the middle of the screen when defocusing? Get that correct first.

If the G70 has the 'EM' test pattern (I can't remember), that's the best one to use to absolutely nail the focusing all over the tube face.

draganm · Joined: 08 Mar 2006 Posts: 8990 Location: Colorado

jbltecnicspro · Joined: 23 Apr 2016 Posts: 512

**Curt Palme** · Posted: Fri Oct 07, 2016 5:48 pm Post subject:

The magnets don't do anything, everything on the G70 is done electronically.

AFryia · Posted: Fri Oct 07, 2016 9:19 pm Post subject:

[quote="jbltecnicspro"][quote="draganm"]

Graeme · Posted: Sat Oct 08, 2016 9:26 am Post subject: focus

I have the same issue with my blue gun on my G70. After finally getting the green to at least become finely focused almost all over the screen. I then turned to the blue and cannot even get it to show the h ao em clearly at all. It will adjust in every action but and pole but for the life of me I cant get it to come into fine focus.

I need to leave it for a few days and then go back and have another go.

Any ideas?

jbltecnicspro · Joined: 23 Apr 2016 Posts: 512

Yeah, I'm not sure. I tried to do the focus again and I can clearly see that the system is adjusting everything in all corners, but I just can't get it correct. I may have a look into the flapping adjustment on the lens to see that it isn't that first. But on the tube face I can still see that it's not perfectly focused so I don't know. A little frustrating...

Also - we watched a (crappy) movie last night! Finally - for the first time in ages. The projector looked alright I guess, but it was a little on the softer side. I was running at 1080i. Should a G70 look "razor" sharp at 1080i? I mean - it's not a flat-panel, so it won't look oversharp, but should I see any haze on text, for example?

AFryia · Posted: Sat Oct 08, 2016 5:20 pm Post subject: Re: focus

AFryia · Posted: Sat Oct 08, 2016 5:55 pm Post subject:

jbltecnicspro · Joined: 23 Apr 2016 Posts: 512

Okay, so I did some more work, and I have to say - Hallelujah for spare parts projectors! I think... Smile

* I swapped lenses and for some reason, after I focused them optically, it made a world of difference. So now everything looks pretty good. Focus is pretty even on red and green, though I have some more flapping adjustments to make as the bottom and right side is a hair softer than the other parts of the screen. Other than that - it looks really good! I'm back to 1080p. Wife and I watched the Terminator last night and it was frickin awesome!

Which now brings me to another point... Our screen sucks. No ifs, and's or but's. It's a home-built one using Carl's fabric, but I'm honestly not that impressed. Even at 1.1 gain it hot spots. I was thinking about possibly getting a Da-Lite 84-inch rollup. Does anyone here have any experience with Model-B roll-ups? How's quality? Or should I just get a decent permanent screen? Who makes a decent (and affordable) 84-inch screen? I was also thinking about Silver Ticket 92 inch screens, but that would mean I'd have to do it all over again (ceiling mount and all) - which I'm not super opposed to. I'm learning more and more as I go.

*To clarify - having two G70's is pretty sweet to interchange parts. But I think having two also tripped me up as to which set of lenses (for example) went with which projector. I went by the overall "design" of the lenses and matched them up. There were three lenses with color-coordinated (red, green, blue) dots on them, and three without. I put the three color dot lenses up and now the projector is well-focused.

jbltecnicspro · Joined: 23 Apr 2016 Posts: 512

Another question, when I use the projector, sometimes I hear a "click" from inside the chassis. Almost like the deflection "click" when it's locking into a signal, except nowhere near the same volume (much softer). I don't see any visual distortions or anything on the picture though. And it seems to slow down and stop after the projector's been on a while. Am I just noticing something thermally expanding and shouldn't be concerned? I've used it now for several hours with no issues, so...