CurtPalme.com Home Theater Forum

**Curt Palme** · Posted: Tue Jun 12, 2012 2:15 pm Post subject: Weird Marquee problem

OK, novices and experts alike, fix this one!

A Marquee that I got in would jump between very low (20?) contrast and 100%, as I'd ramp up the contrast. Ditto when I ramped down. NEver seen this before. Found the problem area quickly, but can you guess what it was?

Jeremy112 · Joined: 28 Sep 2006 Posts: 2649 Location: Fond du Lac, WI

**Curt Palme** · Posted: Tue Jun 12, 2012 2:25 pm Post subject:

Oh, there's a part that opened up alright! Razz

With yours, have you swapped CRT sockets/video amps between tubes?

Nashou66 · Joined: 12 Jan 2007 Posts: 16171 Location: West Seneca NY

The ad834 or 835 on the VIM?

Nashou

Tim in Phoenix · Joined: 21 Oct 2006 Posts: 4409 Location: Phoenix

Uhhh

Glycol on the motherboard?

.

dturco · Posted: Tue Jun 12, 2012 5:02 pm Post subject:

Daughter board on the CLM

**Curt Palme** · Posted: Tue Jun 12, 2012 6:14 pm Post subject:

Sweet, the pros are checking in, and not even close to the correct guess! Hahahahahahaha!

3 more guesses and I'll reveal...

Nashou66 · Joined: 12 Jan 2007 Posts: 16171 Location: West Seneca NY

The Remote.

Nashou

**Curt Palme** · Posted: Tue Jun 12, 2012 6:18 pm Post subject:

Nope. 2 to go.

Boilermaker · Joined: 21 May 2006 Posts: 527

You forgot to use your $500 aftermarket power cord?

Bob

**Curt Palme** · Posted: Tue Jun 12, 2012 6:32 pm Post subject:

That doesn't even count as a guess!

cmjohnson · Joined: 03 Apr 2006 Posts: 5180 Location: Buried under G90s

You found a dead insect on the CLM, shorting two pads, didn't you?

Nashou66 · Joined: 12 Jan 2007 Posts: 16171 Location: West Seneca NY

Bent pin on the VIM to back plane connector?

Nashou

**Curt Palme** · Posted: Tue Jun 12, 2012 7:19 pm Post subject:

Nope. 1 more guess, and I'll spill the beans.

Nashou66 · Joined: 12 Jan 2007 Posts: 16171 Location: West Seneca NY

VNB umbilical cord connected backwards?

Nashou

Nashou66 · Joined: 12 Jan 2007 Posts: 16171 Location: West Seneca NY

I'm just guessing stupid things now

dturco · Posted: Tue Jun 12, 2012 7:25 pm Post subject:

I'll guess at the emitter/receiver issue.

**Curt Palme** · Posted: Tue Jun 12, 2012 7:27 pm Post subject:

OK here goes: The CCM! Ironically, I'd put the projector on the bench (a recent acquisition) to check the ACON board and the CCM that a customer had bought. The set had both installed, but the set didn't recognize either. Then I realized that someone had pulled both out just far enough to be out of module contact range.

I unplugged the set, reseated both the CCM and ACON boards, and ran into this problem where the contrast would strobe when increased or decreased. I lucked out, since I realized that the problem had only started when I'd inserted the boards, so the cause was pretty obvious. Once I pulled the CCM, there was a badly burned 1/4 watt resistor on the board. I rarely see these boards fail, so I just threw it out, since I have about 10 spares, but it's a good one for Marquee owners to remember. THe other bad CCM I had caused all sorts of splotching on an all white field. that was a few years ago, and I thought I'd bought a set with strange wear patterns. Nope, the tubes ended up being mint.

Jeremy112 · Joined: 28 Sep 2006 Posts: 2649 Location: Fond du Lac, WI

**Curt Palme** · Posted: Tue Jun 12, 2012 11:15 pm Post subject:

A resistor on the board went up in smoke. I suspect that a small capacitor has a dead short on it, but as I mentioned, since I have 10 spares, I just threw it out.