Having trouble connecting digital TV receiver to projector

It sounds as if you have a conflict between the format being sent to the projector and what the projector is capable of displaying.
Start by checking the manual for both and match the output image resolution from the receiver to something you know the projector can cope with.  Do not rely on the projector being able to "sense" how to display the output.

Yes this makes sense. I had tried all of the output settings i could find on the receiver, but i'll check the manual too..

Options on the receiver output signal are RGB or CVBS, neither of which works. The output formats are 4:3 letterbox, 4:3 pan scan, and 16:9, again none of these makes any difference.

Might the projector be incompatible with the receiver? How could i check?

What is the receiver make & model?
If it is outputting NTSC into a PAL projector that would account for the black and white image

Clarity CDVB1
The spec seems to include PAL: "Video: MP@ML, PAL, 4:3/16:9"

Do the projector spec also include a NTSC setting? if not then you have a PAL projector, taking a NTSC signal. you will have to convert your NTSC signal to a PAL signal, there are many products that do this. just google NTSC to PAL converter. Hope this helps.

The receiver (Clarity CDVB1) is PAL, and the projector detects this automatically stating "PAL found", but then seems to lose it again, doing this every 2 seconds.

PAL comes in two flavors PAL50 and PAL60 (the difference is the refresh rate in Hz).
Perhaps the difference is the projector detects the PAL format but only can display PAL60 and it's getting PAL50 (or, less commonly vice versa).

Ok thanks. THis could be it. To confirm it, how can i find out if the projector is PAL50 or PAL60? The spec does not seem to mention this. Its an Optoma DS309. Likewise with the receiver Clarity CDVB1.

Checking the projector at least it seems it can cope with all the PAL versions - so that's unlikely to be it :(

Going back to the connection is this direct from s-video socket to s-video cable to s-video socket or are you using any adaptors in-line?

Are you using a 6-pin or 4-pin s-video cable?

Thanks again for pursuing this.

Yes there is an adaptor. THe receiver only has scart out, so i plugged in an adaptor from scart to component + S-VHS, and set a switch to 'OUT'. At the other end is only S-video.

The s-video cable is 4-pin, as are the sockets either end.

Ok sounds good.

Sorry, i just noticed that the adaptor i have converts from SCART to 1 component video (yellow), audio left/right (white/red) , and S-VHS (s-video).

The only adaptor in the projector box is from s-video to s-video + 1 component (yellow).  I have tried adding this to the chain so that the component is now fed to the projector along with the s-video. But alas no improvement.

You are right i am getting only a black&white image so the projector keeps searching every 2 seconds.

As for using VGA, i would need to buy an adaptor. Googling this shows me its a box that needs it own power etc and costs say £40.  I'd prefer just to buy a better receiver - could this help?

Thanks!

Maybe there is some setup on the receiver that indicates you are outputing S-Video and not CVBS (composite Video).
Bruno.

Thanks for your input. This will be helpful for reference. In the end i just replaced the received this worked via component cable.