I got a new large size TV with a VGA port. This TV works with the Apple VGA adapter.
Still does not answer why it won't work with the LT20.
My suspicion is that th the LT20 digital projector is looking for something that the Apple Thunderbolt. Does not transmit or the VGA standard built into th LT 20 is obsolete and no longer supported.
When you plug the projector into the computer, with the projector on, dose the computer reconize a second a 2nd display is connected?
ie: Menu bar, click on the Apple menu, chose System Preferences, click on displays, do you see an arragment tab?
if you do see an arragment tab, try clicking gather display windows. a window should pop up for the projector. What resolution is it set to? is there a lower resolution you could set?
Using microdvi to vga converter sometimes does not recognize the use projects, especially if they are older models of HITACHI. The solution I have is to turn off the amc encontardo. Connect the DVI-VGA converter to projects, TA ON, connect the mac and automatically sets the resolution to the projector and it works. The problem is that to retrieve the LCD resolution is to switch off again and back on mac.