[comp.sys.m6809] COCO3 with Sony CR1311

anderson@marlin.UUCP (Gregory W. Anderson) (12/02/86)

I thought there may some interest in my experience in hooking up the CoCo3 
to a Sony CR1311. I brought the Sony home and immediately connected it via 
composite video to my 3-day old CoCo3. The 80 column mode was completely 
useless. No problem I thought, I'll just kludge together a connector to the
Sony's analog RGB input. It was then that I discovered that the
Sony has only composite sync (negative active) input for the 
analog RGB. This meant building a circuit to combine the separate
vsync and hsync the computer outputs. The circuit I made required
+5 volts which I ended up getting by opening the case and attaching
a wire to the +5 volt pin on the expansion connector. At first I
tried to use the left joystick port for the +5 volt supply but
since there is an 100 ohm resistor in series with the joystick 
supply there was enough of a voltage drop to prevent the joysticks
from working over the full range. The circuit board fit neatly into
the cavity under the expansion port.

The results are great! The 80 column text is sharp and the colors
bright and clear. The text and graphics are definitely sharper 
than on the CM-8.

greg