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[dethbox]

Is there a way to add a VGA connector to the HD pack? Can the needed VGA signals be pulled from the HD pack itself, or is the motherboard the only source for these signals? Thanks.

[EvilWays]

You can install a VGA connector into an HD pack, but you'll either need a Sync-on-Green capable monitor or a circuit built around an LM1881 chip to strip the sync signals from the green signals. The only way to get "true" H/V-sync signals is from the motherboard however, and the only way I can think of to pass it thru to the HD pack is to rewire two of the grounds to pass the signals instead but I'm not sure if that'd be wise.

[dethbox]

With the HD pack open, I only see three wires going to the red, green and blue ports. Where are the ground wires? Just for clarification, the ground wires should be connected to the outside of the ports, and the positive to the center? Thanks.

[appleguru]

That is correct...

BTW, /me has some extra LM1881 chips lying around if anyone wants any... Actually, they're EL1881's, the successor to the LM1881. they do they same thing and have the same pinouts, etc..

[dethbox]

Could you post a pic of the chips you have? Ive got a bunch of old PCB's laying around that may have one on them, a picture would help to identify it. Thanks.

[appleguru]

Don't have a digi cam around atm, but the LM1881 looks like this:

(IMG:http://partsandkits.com/LM1881N.jpg)

Those are made by National Semi...

My EL1881's, made by Intersil, look similar; info online here:

http://www.intersil.com/products/deviceinfo.asp?pn=EL1881

[ZASADAR]

im told there is an easy way around this look for a cable to use hdtv to hd pc monitor then get a converter to convert HDvga to vga

[appleguru]

Many monitors/projectors support sync-on-green, and if so, no sync chip is needed and a 'standard' Component --> VGA cable can be used. However, many also don't, and then the chip is needed to supply a valid image signal.