I found a circuit diagram online for connecting a PCW to an external monitor. So I made it, connected it to a Video to VGA convert box, and then to an LCD monitor. It does display something vaguely recognisable, but it isn't very good. Whether it's because I built it badly, so it's picking up lots of interference, or because the converter box isn't very good, or because the circuit is wrong, or because the monitor doesn't like the resolution, I don't know. I'm sure I can get there eventually. (I'm kind of tempted to use my FPGA board to convert the signal to HDMI…)