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[Jeff Friesen]

When we turn on our ceiling fans, lower our screen, plug in a guitar, or someone in our sanctuary gets a static shock from someone, we loose our signal from our computer to our projector for a couple seconds (it flashes to the blue screen that is default when there is no signal).  

Any computer I use has this problem, (we currently use a computer with a dual-head graphics card), we have switched our vga splitter/amplifier and still have this problem.  Any ideas?

[Aaron McQueen]

Check to make sure the power for the projector is grouded.  What projector do you have?

[psron]

There are many possibile sources of the problem, but most can be resolved by using a RGBHV-over-CAT5 cabling system.  These allow use of VERY inexpensive wiring for projectors for 350 up to as much as 1000 feet.  We use them, they work great, and solve all ground-loop issues as well as many other issues.

These are "active" systems, requiring AC/DC power at one or both ends (depending on total run length).

Extron/Inline makes these, but there are several other good ones for less $$ (such as one of my favorite suppliers - Kramer Electronics) - another I just found - Altinex

Search for "twisted pair" and "RGBHV".

[Jeff Friesen]

We have a Sanyo PLC-XU31 projector.  We don't have the problem when we are running our DVD player to the projector via RCA cable.

[Kevin Hoober]

Sounds like the PJ is loosing sync.  How long is the cable run, and what is the cable?  I'm guessing you are pushing the upper limits of length for the type of cable you are using.  I run '5 wire' (5 coaxes in 1 jacket) when I do a PJ install.  Coax size depends on length of run (smaller the coax, the more lossy it is...hence long run = big coax)

Kevin

[Jeff Friesen]

We are running about 150 feet of VGA cable...

Thanks for all the advice, the problem disappeared (I'm not sure that we did anything - in my line of work, I don't doubt the miraculous!)

[Kevin Maxwell AKA TheMAXX]

The problem may have disappeared because the weather has warmed up and the heat (that dries the air and generally causes static) isn’t on as much this time of year. So you may still have a problem its just that the symptoms have stopped at the moment.

A couple of things that I would suggest in addition to what some of the others have already recommended. Change the blue default screen to black (in the menus) so if this does happen again it isn’t as distracting. Check to see if the source is set to auto sync and try changing it so it doesn’t have to hunt for sync. I have seen some computer / projector combinations that don’t work well together when auto sync is left on.

I hope this is of some help.

[Kevin Hoober]

friesenjeff wrote on Tue, 06 June 2006 18:32

We are running about 150 feet of VGA cable...

is it a "computer data/control cable" type VGA cable--the jacket is usually ribbed like a vacuum cord.  If it is, the lines ran for sync are likely not shielded and this could be causing your problem with EMI/RFI.  I'd suggest you go to a cable made of 5 coaxes (1 for each of RGBHV) I've bought some cable assemblies from Have, inc before--http://store.haveinc.com/Ebus30/Parts/Part.asp?Part= 30VGA53CFB%2D15MM%2D150&Material_Code=CURRENT they do good work...but it ain't cheap.  150' is a long, long way!

I also agree w/ Kevin (of course I would); I doubt you've seen the end of this problem

Kevin Hoober

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