Cobra 25 Plus

1.	Remove the covers from the unit and locate crystal X1 (10.240 MHZ), just left of coil L6. Tum the unit over and locate the pins of X1 on the circuit board side. Carefully cut the dog leg trace as close to the illustration as possible.
2.	Still looking at the diagram, solder the small 100 pf capacitor to the circuit points shown. If the points are not clear, the capacitor should be from the junction of FT-1 and L5, to the junction of R28 (1K) and TR-10.
3.	Solder the expanders White wire to the cut trace away from the xtal (X1). Solder the expanders Green wire to the cut trace (xtal side). If interference from normal channels is present, a 22 pf capacitor may have to be soldered in series with the Green wire.
4.	Solder the expanders Red wire to the switched side of the volume control (+13.8 VDC).
5.	Solder the expanders Black wire to cdrcuit board ground.
6.	Solder a short ground wire from the top of X1 xtal to the corner of coil L6. This seems to provide a shielding effect to reduce interference on the extra channels.

* Tum the unit on and check all channels for transmit Adjust the VCO coil slightly to bring in any missing channels if necessary. Flip the switch to the extra channel side and tune the selector to channel 40. Adjust coil L2 for maximum receive. Tune the selector to channel 10, and tune L4, and L5 for maximum receive. Notice that coil L4 will tune at maximum on the normal channels, and at a deferent position (counter clockwise) on the extra channels. By flipping the switch back and forth, and tuning coil L4. A compromise tuning position can be achieved. Try to keep the Green and White wires slightly apart when routing them since feedback between them can cause strong station interference from the nominal channels. Tune coil L12 for transmit.