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Take a look at our February Specials

  • Overview
  • Specs
  • Cables
  • FAQ
  • Reviews
  • Manuals & Downloads
  • Price List/Order



At Elecraft, we know how rewarding low-power operation can be; that's why we offer a range of QRP transceivers optimized for portable and emergency communications. But there are times when higher power is needed to get the job done, and this is where the KXPA100 comes in. Whether you're using it with a KX3 or other low-power rig, this versatile, 100-W amplifier can automatically and silently boost your signal to overcome difficult band conditions. 

If you also have the KXAT100 module installed, you'll have the advantages of a wide-range automatic antenna tuner (ATU). The KXAT100 provides automatic retuning, instant recall of tuning element settings, and dual antenna jacks.

When used with the KX3 and its amplifier control cable, the ATU's TUNE switch, ANT switch, and menu functions can all be controlled directly from the KX3. In any setting--fixed, mobile, or field--we hope you find the rugged, compact KXPA100 a valuable addition to your station.





    • 100 watts at 13.8 V, 1.8 to 29.7 MHz and 80 watts 50-54 MHz PEP CW/SSB/DATA; ± 1 dB
    • 13.8 VDC powered; 20 A typical current drain  (11 V with lower output. 15 V max)
    • 7 lbs with KXAT100 installed.  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 (KXAT100 ATU option)
    • Second antenna jack provided with KXAT100 ATU option; controlled by KX3 or the KX2
    • Fast, bright LED bar graphs for power and status; KXAT100 ATU option adds SWR bar graph
    • Seamless integration with the Elecraft KX3 and KX2 transceivers
    • Works well with any low-power transceiver, requiring only RF and PA KEY inputs
    • RF-based frequency counter automatically switches bands with any rig
    • Support band-data input for the K3/10, KX3, Yaesu FT-817, Icom IC-703, and other rigs
    • Dual APP power connectors to connect the KX2/KX3 directly to the back of the KXPA100 amp for ease of placement on the operating position.
    • KXPA100's PC port allows use of remote-control and logging applications with the KX3 without software configuration changes
    • KXAT100 ATU settings saved per band, per band segment, and per antenna for instant recall



    • KXPACBL adapter connects KX3 to the KXPA100 with a single cable for keying, band data, and control
    • KXAT100 internal ATU option matches 10:1 SWR (5:1 typical on 160 m and 6 m); uses Elecraft's fast matching algorithm
    • KX2ACBL provides the connections from a KX2 - be sure to order the KXPACBL cable kit to complete the interface





    Q: What is required to connect the KXPA100 to a KX3?

    A: When you purchase the KXPACBL cable set, you'll be able to obtain full optimized operation.  Features include:  Power up/down of the KXPA100 when the KX3 is powered up, ability of the KX3 to be turned up to 100 watts, and control of the KXPA100's autotuner.  In other words, you'll have a complete 100 watt, high performance transceiver.

    Q: Can I hook up the PX3 and KXPA100 to the KX3 at the same time?

    A: Yes, you can.  The wiring diagrams are found in the PX3 Owners Manual.  When they are connected, you'll create a complete, 100 watt, high performance transceiver with panadapter. 

    Q: I already have a KX3 with its internal 20 watt tuner, do I need to purchase the KXAT100, 100 watt tuner for the KXPA100 I want to purchase?

    A: Yes, the 100 watt tuner, while it fits into the same cabinet as the KXPA100 amp, it is in the signal chain between the 100 watt amp and the antennas.  When you use the KXPA100 and its internal tuner system together, the KX3's internal autotuner will be BYPassed.  This is done automatically when the KXPA100 is connected to the KX3.  Instructions are found in the KXPA100 Owners Manual.

    Q: Can the KXPA100 be used with other QRP rigs?

    A: Yes, you can connect any QRP radio to the KXPA100.  All it will take is 5.0 watts input to the KXPA100 for 100 watts output.

    Q: What cables come in the box with the KXPA100?

    A: You'll receive a power cable with fuses installed in line.  This cable will have ring terminals for connection to a suitable power supply and will have Anderson Power Pole connections on the other end for connection to the KXPA100. 

    There will also be an RCA-to-RCA cable to connect up to non-Elecraft QRP radios for keying the amp.



    KXPA100 AMP w/KXAT100 ATU for KX2, KX3 or QRP Rigs (incl. DC power cable) Quantity Price
    KXPA100-AT-K KXPA100-AT 100W Ext Amp with KXAT100 100W ATU, Kit $1,679.95
    KXPA100-AT-F KXPA100-AT 100W Ext Amp with KXAT100 100W ATU, Factory Assemble, $35 Special Discount $1,664.95 $1,699.95
    KXUSB KXUSB USB Cable (N/C With KXPA100 Purchase) $0.00
    KXSER SWAP No charge for exchanging KXUSB for a KXSER $0.00

    KXPA100 Amp for KX2, KX3 or QRP Rigs (incl. DC power cable) Quantity Price
    KXPA100-K KXPA100 100 W External Amplifier-Modular Kit (incl. DC power cable) $1,359.95
    KXPA100-F KXPA100 100 W External Amplifier-Assembled (incl. DC power cable), $30 Special Discount $1,349.95 $1,379.95
    KXUSB KXUSB USB Cable (N/C With KXPA100 Purchase) $0.00
    KXSER SWAP No charge for exchanging KXUSB for a KXSER $0.00

    KXPA100 Option (For KXPA100 Owners) Quantity Price
    KXAT100-K KXAT100 Internal 100W ATU (Kit) $439.95

    KXPA100 Cables Quantity Price
    KXPACBL KXPACBL, KXPA100 Integrated Cable $59.95
    KX2ACBL KX2ACBL, KX2 Accessory Cable $9.95
    KXFT817CBL KXPA100 Interface Cable $49.95
    KXUSBa KXUSB-a Extra Cable - USB RS232 to 3.5mm Cable $39.95
    KXSER-a KXSER-a Additional RS232 communication cable with 9-pin connector $39.95

    Books Quantity Price
    E740241 The Elecraft KX-Line book by Fred Cady $45.00
    E740306 The KX2 Companion Guide to the KXPA100 and KXAT100 by Fred Cady $25.00

    Elecraft Wear Quantity Price
    KHAT Elecraft Logo Hat $24.00
    MWT-Shirt Make Waves T-Shirt SLight Gray $22.00
    MWT-Shirt Make Waves T-Shirt MLight Gray $22.00
    MWT-Shirt Make Waves T-Shirt LLight Gray $22.00
    MWT-Shirt Make Waves T-Shirt XLLight Gray $22.00
    MWT-Shirt Make Waves T-Shirt XXLLight Gray $22.00
    MWT-Shirt Make Waves T-Shirt XXXLLight Gray $22.00
    T-Shirt Elecraft Logo T-Shirt S--Light Gray $22.00
    T-Shirt Elecraft Logo T-Shirt M--Light Gray $22.00
    T-Shirt Elecraft Logo T-Shirt L--Light Gray $22.00
    T-Shirt Elecraft Logo T-Shirt XL--Light Gray $22.00
    T-Shirt Elecraft Logo T-Shirt XXL--Light Gray $22.00
    T-Shirt Elecraft Logo T-Shirt XXXL--Light Gray $22.00

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