RE: "PIXIE" S/C radio from the 70's
Your memory is a bit off.
Obtain a copy of the May/June 1964 issue of American Modeler and there is a review of the transmitter and a schematic.
The Pixie was a bit different in that seems to me, the signal button was also the on/off. Thus you never turned on the transmitter, just pushed the button.
Wm.