This compilation of information was compiled by forum member Joust (Barry)
with permission from the original author, Mike Parker. Thanks for putting this together Barry!
Note: The procedures outlined in this section require a good knowledge of
electronics and soldering.
The following contains contributions from various sources, the largest
contributor being Mike Parker. I also collected tidbits from others as well.
(Sly for one.) I’d like to thank Mike for these on behalf of the Marquee
Projector community. Most of these are not performance mods. They are merely
mods to bring an earlier model projector up to the latest revisions.
Note: If you have anything you would like to add, PM me (Joust) on the
curtpalme.com forum and I’ll review it and see it gets added. Thank you for your
attention.
Sections are divided into the following:
1. LVPS
2. HVPS
3. Neck Boards
4. VIM
5. Horizontal Deflection Module
6. Vertical Deflection Module
7. Convergence
8. Contrast Correction
9. How to "Hot Rod" a Marquee
Notes on OP-AMPS
Most of the later Marquees use the CLC449 (Comlinear) op-amp. They replaced
the CLC409 and H1100. Both of these chips had a roll off problem and could cause
smearing and slight distortion in the image when used on certain resolutions.
The H1100 may not show a problem, and may not be a problem from testing, so the
replacement of the H1100 is an upgrade option. CLC449 is obsolete.
So far I've received very good reports from the chip upgrade on the neck
boards, and some have already replaced the chips on the VIM, with very good
results.
New chip options:
- Harris (Intersil) HFA1100's: They're basically the same bandwidth and would
work well.
- National Semiconductor LMH6702: That chip is supposed to be a direct
replacement for the CLC449 that were used in the Marquees, and is now
discontinued. IT WILL NOT FUNCTION PROPERLY IN THE VIM -- Do not use!
- I read that the LMH6705 is intended to replace the CLC449 but it is not released
yet.
- The MAX4224ESA (Dallas Semiconductor) chips: I've already
installed them on a neck board, tested and viewed. So far this chip seems to be
a perfect substitute. I could not even notice any difference in the gray scale.
This chip seems to be a good replacement for the now obsolete CLC449. The MAX is
a much faster chip than the CLC409, so I would suggest that you first try
changing the resistors values to around 249 ohm or something near that. 120 ohm
feedback/ground resistor is definitely too low of a value for the speed of the
Max4224. I would also replace the bypass caps and put one 4.7 mfd and one 0.1
mfd in parallel on each rail (+/-) of the chip. If used on the neck board,
replace R12 (261 ohm) with a 331 ohm, but it must be a metal film @ 1 %. R12 is
the feedback resistor for U2.
- Burr-Brown OPA658 (not the 685).
To check you video chain for the problem:
The CLC409's were no longer used in the Marquee neck boards after 1995 (my
guess).
If so, and no smear, your projector would more likely have either the CLC449 or
H1100's.
If your projector is pretty well aligned, you could also try running AVIA at
720x480P (native rate of the DVD) and look at the 'sharpness' pattern and the 'multiburst'
patterns for detail. Compare the detail of these patterns using a second
resolution of 1440x960P.
Any well aligned Marquee should be able to handle both of these resolutions
quite well. The 1440x960 using the above test patterns in AVIA should let you
know if there's a problem in the video chain. And this test would also include
the cables.
If you see no smear, your projector would more likely have either the CLC449 or
H1100's
(this is secret stuff). Set it up above the resolution of use, copy down to your
desired resolution - touch-up. The Marquees will have much better color tracking
when setup in the high band, plus you'll tame the dots better.
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