There is very little information on Koyo CH-777. However, it looks identical (except for the color) to Corona CH-707, about which I also do not know much. So if you are reading it and know anything or have a manual or have the actual machine, I would really appreciate it if you get in touch with me.

Koyo KH-777 is very likely a standard-gauge knitting machine (i.e., needles are 4.5 mm apart). It looks like a basic knitting machine (no buttons or knobs on the needlebed), but the carriage has two sets of turn-knobs, similar to other Koyo and Corona knitting machines. Thus, if you can’t find information on Koyo KH-777, look for info on other Corona and Koyo machines.