[John Folsom]

Here is a schematic for the Hickok 656XC. This generator has a color selector switch selecting 1. NTSC color bars (in a non-standard order), 2. G-Y and G-Y@90degrees bars and 3 R-Y and B-Y bars

Hickok also mad a model 655XC, almost identical except the color selector selects 1 Same as 656XC 2 I and Q bars 3 same as 656XC

Can't seem to lay my hands on the schematic for the 655XC, but if someone needs it, I will keep looking.