We can build this unit for you, load the latest firmware and test it. Just add this option.

The Elecraft KXPA100 amplifier is a 100W power amplifier suitable for use with most QRP radios. It has been designed with the KX3 in mind but any radio with 5W output can be used

KXPA100-K is the kit version without ATU and comes supplied as a modular kit (no soldering required).

Features

• OutPut: 100 W on 160-6 m with 5 W input typical
• power: 13.8 VDC; 20 A typical current drain (11 V with lower output. 15V max)
• Weight: 7 lbs with optional KXAT100 installed.
• Dimensions: 10" x 5.125" x 4.25"
• Compact unit ideal for both desktop and mobile use
• Solid-state diode T/R switching — fast, silent T/R and QSK
• Large convection-cooled heat sink for reliable and quiet operation
• Modern design with rugged MOSFET output stage
• Internal wide-range automatic antenna tuner option (KXAT100 ATU option)
• Second antenna jack provided with KXAT100 ATU option; controlled by KX3's ANT switch
• Fast, bright LED bar graphs for power and status; KXAT100 ATU option adds SWR bar graph
• Seamless integration with the Elecraft KX3 transceiver (requires KXPACBL)
• Works well with any low-power transceiver, requiring only RF and PA KEY inputs
• RF-based frequency counter automatically switches bands with any rig
• Optional band-data input support the K3/10, KX3, Yaesu FT-817, Icom IC-703, and other rigs
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• Dual APP power connectors for additional friction-fit if needed (mobile); optional daisy-chaining of 13.8 V to power rig
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• Optional KXPACBL adapter connects KX3 to the KXPA100 with a single cable for keying, band data, and control
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• KXPA100's PC port allows use of remote-control and logging applications with the KX3 without software configuration changes
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• KXAT100 internal ATU option matches 10:1 SWR (5:1 typical on 160 m and 6 m); uses Elecraft's fast matching algorithm
• KXAT100 ATU settings saved per band, per band segment, and per antenna for instant recall
• IMPORTANT: If you are using a KX3 with your KXPA100, you must load the latest KX3 firmware (MCU 1.76 or newer) before use.

Depending upon what radio you are using, decides what additional leads you need.

• KX3 - You will need the KXPACBL
• KX2 - You will need the the KXPACBL plus the KX2ACBL
• FT-817 - You will need KXFT817CBL

*Please note that picture shows KXPA100 with optional KXAT100 installed