From The RadioReference Wiki
Quote from Greg Knox's TXT file: "To get at it, remove the bottom cover of the radio. Orient the radio so that the rectangular silver shielded box is at the top of the radio and the rotary VFO knob is at the lower right hand corner. The tap point is a solder pad at the lower terminus of a vertical trace about an inch long. The pad is located at a point 3.6" from the top edge of the circuit board and 2.6" to the left of the right edge of the circuit board."
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