Finally, if you all will indulge the non-vintageness, I found this machine in a local Goodwill for $3.67 and couldn't resist. It is a battery operated lock stitch machine using class 15 bobbins; it came with no needle. Mysteriously enough it did not work when I plugged it in. Using jumper wires I could make the motor turn, so it wasn't that. I ended up eliminating the Hi/Lo (really Lo/Lo-er) and On/Off buttons; the foot pedal completes the circuit for the motor.
Once the motor was turning it was time to test it. I assumed a 15x1 needle, but could not make stitches. I tried a shorter needle, a cc1221, and was able to make stitches, ugly stitches, but stitches nonetheless. I could not resolve myself though to this having been engineered to take a mostly obsolete needle, so back apart it went to check the timing. Turns out the timing on this works about the same as any other machine. I loosened the red-circled screws and was able to move that vertical shaft allowing me to turn the lower horizontal shaft to adjust the timing. I did all this with a 15x1 needle in place, and finally made it work...then the batteries died. The next step will be to wire in an AC adapter.