The HF50-12F MOSFET (Q35 and Q40) finals are no longer available.
ACTION: We have switched to a new final, the 2SC2290. This can be installed in place of the old finals provided you do the following:
- 1. Be sure to replace both finals with the 2SC2290. Do not use one old final and one new final.
- 2. Replace R355 and R356 with a 120 ohm 2W resistor.
- 3. The hole in the PCB may need to be enlarged slightly to accommodate the new transistor.
See image for the location of R355 and R356.
Cobra part numbers:
- 2SC2290: 010-119
- 120 ohm 2W resistor: 010-094
ADJUSTMENTS: Check bias and transmit power.