This is a homebrew amplifier for 160 through 10m bands.
The amp works well on 30m and higher frequency bands. While operating FT8 on lower frequency bands, T2 and T3 are heating up and causing efficiency, and hence output power, to drop. I need to investigate this.
Low Pass Filters must be added in order to comply with FCC requirements. Suitable Low Pass Filters include https://www.w6pql.com/a_1.5kw_lpf_for_160-6m.htm.
The heatsink is a Communications Concepts, Inc., Model 55HS.
Ground the Bias Control, pin 1 on J3, to enable the amp by applying bias to the MRF101s. With gate bias voltage initially set to zero volts, R7 and R8 are adjusted for 100mA quiescent drain current on the MRF101AN and MRF101BN, respectively.