Modification notes for:
Regent Model MS-401

(See bottom view, Figure 1)
Note positions of controls, for reassembly.
Pull off Mode Switch handle and Sensitivity knob.
Remove small Phillips screw, deep in 1/8" hole.

(See rear and side views, Figure 2a, 2b)
Pry at shaded rectangles to unsnap locks, and lift off cover.
Slide out printed circuit assembly, wires, and mounting knuckle.

(See PCB drawing, Figure 3)
1) Remove four components indicated by dashed lines:
R2, R4, C5 (small disk), C1 (large, red-brown, rectangular)

2) Remove Black wire from terminal P1, and reattach at {A}.

3) Add a new Red wire at terminal P1, where Black lead used to be.
Thread new wire out through knuckle parts (will need to remove small screw holding knuckle together, temporarily).

4) Reassemble:
Slide PCB into housing, ensuring it slips between card guides.
Snap knob and switch handle back in place.
Note that all four wires curve over edge of PCB and through slot in panel attached to cover, then through knuckle.
Snap cover on, then replace screw.

Black - Power return, negative side for batteries.
White - Power high, +18 V (2 x 9V batteries) works well.
Consumes 3.4 mA in 'OFF' state, 14 mA 'ON'

Red & Red - Isolated output contacts:
240 VAC / 10 Amp
120 VAC / 20 Amp
24 VAC / 10 Amp

MS401 Figures