The A600 v1.2 is an improved version of the original A600 design that was awarded 2nd place in the NXP Homebrew RF Design Challenge 2019.
Improvements include separate chokes for feeding DC to the power transistors drains, improved overall gain and gain flatness, improved input matching (under 1.5:1 across the whole frequency range) and readjusted the bias circuit for more accurate thermal tracking.
This is an Advanced level kit and assumes you have a good understanding of electronics. The PCB is supplied with the surface-mount components already installed, but some of the parts supplied in this kit will require assembly and soldering. You will also have to source a power supply and a large heatsink, drill and tap the heatsink (and included copper heat spreader) and build your choice of input-output switching circuitry. Recommendations are included in the provided Assembly Instructions.
The Sensor Port provides sensor outputs for measuring circuit parameters such as supply voltage, supply current, heatsink temperature, forward power and reflected power. They are all analog signals in the 0-5V range and can be easily interfaced with a microcontroller of your choice (eg: Arduino) to implement display or protection routines. The signals are described in the provided Assembly Instructions.
To use this amplifier on the air and meet legal requirements, it is recommended you use a bank of switchable Low Pass Filters and make sure you don’t overdrive it beyond the design output power.