A600 HF/VHF 600W Linear Amplifier Kit

(2 customer reviews)


  • Over 600W from 1.8MHz to 54MHz, 450W at 70MHz
  • 24dB typical gain, needs less than 5W drive
  • High efficiency, typical draw 20A @ 44V.
  • Onboard sensors for supply voltage, current draw, heatsink temperature, forward and reflected RF power, drive RF power
  • Connectors for a separate Low Pass Filter bank
  • Compact size, PCB is just 190x100mm
  • Can be set up to take up to 100W drive
  • NXP Homebrew RF Design Challenge award winner

All details are described in the included documentation. This is a kit and requires assembly, heatsink is not included. See details on older versions here and here.

Currently not in stock. Orders will be shipped the first week of September.

SKU: A600KITv30 Category:


The v3.0 is the latest evolution of the A600 design that was awarded 2nd place in the NXP Homebrew RF Design Challenge 2019.

As v2.0 already offered excellent RF performance, v2.1 and later versions add more ruggedness:

    • Wider DC tracks, upgraded T5 and doubled feedback resistors minimize heating even under long transmit cycles at full power (digital modes, contesting etc.)
    • Input TVS diodes adds another layer of protection against accidental excessive drive
    • Larger L1 reduces EMI from the board and improves filtering at high currents

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 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, input drive 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.

Additional information

Weight 0.45 kg
Customs code


Power devices

not included, 2x MRF300

2 reviews for A600 HF/VHF 600W Linear Amplifier Kit

  1. Raoul (verified owner)

    first “light” test today. 25watt through a 10 db attenuator, read 350w on my MN2000 Drake . 50 ohm high power dummy load . 🙂 73 Raoul

  2. SP9FKP

    On schematic is error. R9 is wrong connected, must be connected to gate of Q2.

    • Razvan

      Fixed, thank you!

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  • Output power (P1dB): over 600W from 1.8MHz to 54MHz, 450W @ 72MHz
  • Gain: 24dB typical, drops to 22dB on 50MHz and 20dB at 72Mhz
  • Supply: 44V @ 20A typical, 48V/25A recommended
  • Connectors: SMA for RF signals, screw terminals for PSU, 2.54mm spaced header for sensor port
  • Size: 190x100mm
  • Heatsink: not included, 0.1C/W or better recommended

Kit contents

  • 190*100mm PCB board with installed SMD parts
  • All required additional parts in separate bags
  • RF transformers & inductors in separate bags (require winding)
  • Assembly instructions
  • Optional: pair of MRF300AN & MRF300BN LDMOS RF power transistors (make sure you select when ordering)