sharp lcd projector auto shutoff

[diylabs]

The clicking means that they are activated. I think what happens is that the ballast builds up a charge, activates the relays to hopefully release that charge, then once a certain current draw occurs (when the lamp arc ignites) the ballast sends some signal to the main board that says whether the lamp lighted correctly. This whole time I've been assuming that sending a signal manually on the data link was the way to go, but I think that li_gangyi has the right idea - tricking the ballast into sending that signal for us would be easier. Of course, if someone with a working proejctor could use an oscillascope or voltmeter to test the 4 wires for us to see what data is being sent, that would be awesome and eliminate the need for having a ballast anymore Anyone interested in doing that for us?

[kahurt]

I found a service manual on the internet . Do you think it will help figure this out?

[kahurt]

I unpluged the jumper wire and turned it on . this time i didn't hear the relay click

[li_gangyi]

ok...let's have a look of the service manual...I suppose if you unplug the wires...you pulled something out that was controlling the ballast (power on and power off) I dun have a projector...I'm currently gathering parts to build a simple one...but I've messed around with quite a few...mostly hitachi ones...so I'm not too sure...the service manual should have something that will get us closer though...

[kahurt]

I think I'll order the manual . I don't know how long it will take to get here . when I get it i'll let you know what it says

[li_gangyi]

manz...you have to get the manual?? I say then we work it out slowly without the manual...perhaps you can ask the seller if it contains any information on it before ordering...it would be a shame to spend some $$$ on a manual without the information you're looking for...

[kahurt]

I had a thought . I wonder if I wired a resistor in where the lamp goes if that might fool the relay.

[li_gangyi]

hmm...I dun think that will work..coz the lamp is non-ohmic...that is the resistance will vary with temperature...you might wanna try it...but make sure you dun fry the ballast~!!!

[kahurt]

evidently they wont sell a service manual unless your a certafied sharp tech. anybody know where i could find the service manual?

[kahurt]

I disconnected the entire ballast board then I got nothing not even the standby light . I'm not giving up yet . I'm still looking for a service manual.