Does anyone know how to activate the HD input on a Mitsubishi WS-73903. This was one of Mits 1st HD televisions and has RGB with Hor and Vert Sync. Was installed around "2000". Is has a proprietary hookup intended for a Mit HD box and according to the manual it appears that the box would have turned on the HD input when activated. I have tried the Mit HD codes that work for many of the other jobs we have done with no luck. A similar model had a place in the setup menu to activate, but not this model. Definitely has 1080 engraved on the front of the TV. The component inputs will not support HD as other models either. Have tried a couple of 15 pin to component convertors also.

When I worked with this tv I had to get the upgrade box.

Mits sels 2 Adaptors that work with this set. A $250 Adaptor cable/box and a "Promise Module" that had a Terestrial tuner in it as well for arond $1000 I think.

Warning attempt at your own risk

Press MENU and 1370
Use the up down toggle buttons to scroll down to DTV
Press Enter in succession until you see HD
Press the Mennu button twice to exit

Dont touch anything else unless you know your way around

Thanks Mat
I have to be back on site on Friday and give it a try.
Is that something that you have done personally? Any problems? Anyway to make it so that the customer could do it without worry? Thanks for your help.

Yes I have tried this and It works fine

I did notice some loss of information on the upper left corner of text(the tops of some text), but I worked so long to even get HDTV (with the use of a Samsung receiver) that it didnt even matter at that point.

Plus i'm sure the Tv was a little out of convergence.

Good luck.

Let me know if it works ok and if you need more help.