Check Out Winter Specials!

  • KPA500-F_KPA500 500w Amplifier, Assembled NOTE: Select 1 PWR Cable Below
  • Overview
  • PowerCombo
  • Specs
  • Accessories
  • Reviews
  • FAQ
  • Manuals
  • Price List/Order



500+ Watts in a compact package the size of the K3S.
The 500-watt solid-state amp that integrates so well with your station, you’ll think it's reading your mind.

Exactly the same size as the K3S transceiver, the KPA500 fills out our K3S-P3-KPA500 'K-Line'. The KPA500 features 160-6M coverage, instant RF-based band switching with any radio, alphanumeric status display, bright LED bar graphs, and a rugged, internal linear supply. The amp’s manual band switches may be used to directly change bands on the K3S. Also the K3S can even select per-band amplifier drive levels automatically when the amp is placed into operate mode, so you’ll rarely need to adjust power output.

But the KPA500 is not just limited to use with the K3S – it is fully compatible with most radios. (Only amplifier keying (PTT) and RF are required for operation including instant RF frequency sensing, fully automatic band switching.)

KPA500 Features:

  • 500W, Compact, Solid State FET amplifier for 160-6 m
  • Works and auto band selects with any radio that provides Key-Out and RF signals.
  • Exactly the same size as the K3S
  • 26 lbs, 12 kg
  • Internal low noise linear power supply: 100-120, 200-240 VAC, 50/60 Hz operation
  • Instant-on operation
  • Rugged, conservative design with smart soft and hard fault detection
  • Intelligently reduces power by 2.5 dB temporarily when presented with input overdrive or a high SWR, allowing you to quickly reduce your drive to compensate without dropping the amplifier off-line. The amp automatically recovers to full power once the soft fault condition is corrected.
  • Excessive overdrive or SWR events instantly place the amp safely into protective stand-by
  • Works with any radio that supplies PTT to Ground
  • Ultra high speed QSK. Silent, diode switched T/R
  • Super fast RF sensing band selection. Only PTT and RF required for fully automatic band changing operation.
  • Can receive band data information from most radios that supply it
  • Fully remote controllable
  • Six speed temperature sensing fan
  • Advanced integration with the K3S using the optional KPAK3AUX cable:
  • KPA500 band buttons drive the K3S band and drive level
  • Band data is sent from K3S to KPA500 before TX
  • PTT included in cable, external PTT cable not required
  • The K3S senses KPA500 operate/standby state and adjusts drive power between two memorized levels on each band.
  • Upgrading software in the KPA500, like our K3S and P3, takes just one click, thanks to our convenient KPA500 Utility PC application. T
  • Available as Factory Assembled, or as a Modular, No-Soldering Kit





KPA500 & KAT500 PowerCombo Package

Plays Well With Most Popular Rigs!

Add more punch to your signal with Elecraft's Power Combo and take your transceiver to a full 500 watts out.

In addition to the K3 and K3S, the DXpedition-proven KPA500 and KAT500 PowerCombo is available for most recent Icom, Yaesu, Kenwood and Flex transceivers. We've taken the guesswork out of operating by providing cabling and instructions for some of the most popular rigs in shacks today.


Models Supported

Users Built-in Frequency Counter 

Reads Transceiver Frequency


TS-590,TS-990,TS-2000, TS-570, TS-480

Older models

TS-830,TS-850,TS-870, TS-930,TS-950

Yes Custom Cable*

FT-891/991A series FT-857/897(D) series FTDX-1200, FT-450(D), FT-100(D) series

Older models

FT-950, FT-840, FT-900, FT-847

Yes Custom Cable*

IC-7610, IC-7300, IC-7600, IC-756 series

Other models

IC-706/7000 radios

Yes Yes

All 6xxx Series radios

Yes Yes



 App Notes for the PowerCombo 
K3 & K3S Icom 7300 Flex 6500
Flex 6300 Icom 756 Pro III Kenwood TS570
Kenwood TS590 Kenwood TS2000 Yaesu FT857/897
Yeasu FT990/991 Yaesu FT950 Yaesu FTdx1200
Yaesu FTdx3000 KAT500 Learn More

Don't see your radio?  Contact Us!





Frequency Range All Amateur Bands from 1.8 to 29.7 MHz and 50 to 54 MHz
Supply Voltage and Current 100 to 125 VAC or 200 to 250 VAC, 50/60 Hz, approx. 1000 VA
Weight 26 lbs (11.8 kilograms)
Size Enclosure only, 4.0 x 10.8 x 10.0 in., HWD (10.2 x 27.4 x 25.4 cm). With projections, 4.4 x 10.8 x 11.8 in. (11.2 x 28.4 x 30.0 cm).  When installing, allow an additional 2” (5.1 cm) behind the fan and above the top cover for unrestricted air flow.
Power Output 500 watts PEP CW/SSB/Data
Duty Cycle at 500 Watts 10 minutes key down / 5 minutes standby
Drive Power 30 to 40 watts for 500 watts output
Input VSWR Less than 1.5:1
ALC Out Negative-going, adjustable
Metering Power Output, SWR (bargraph and on the LCD display), supply voltage and current, temperature, frequency band
PA Current 20 A maximum
PA Voltage 60 VDC, nominal
Heat Sink Temperature 90°C, maximum
Key In +5V maximum, open circuit on receive, closed to ground on transmit (1 mA max.)
Efficiency Approximately 50%





  • KPAK3AUX: Connects the KPA500 to K3/K3S that enables all of the features of the K-Line.  This turns your K-Line into a complete, fully integrated 500 watt transceiver.
  • E980190:  DB15 Y- Cable - allows you to connect additional antenna switches and controllers to the K-Line system.

    Amplifiers Cables for Non-Elecraft Transceivers



    Q: What do I need to operate KPA500 with a K3 or K3S?

    A: When you order the KPA500, please be sure to order the KPAK3AUX cable kit.  This provides Enhanced Mode operation with the K3/K3S radios.  Enhanced Mode provides 2 power level settings on a per-band basis.  This allows the operator to have 2 RF output settings depending on whether the KPA500 is in Operate mode or in Standby mode.  Once set up, the operator does not have remember to turn down drive power from the K3/K3S when switching the KPA500 into Operate mode.  This means fast search and pounce operation.

    Q: I have 120 volts in the shack right now but plan to add 220 volts very soon.  How hard is it to change the KPA500 to another input voltage?

    A: The KPA500 can be switched between 120 volts and 220/240 volts AC without opening the cabinet.  The fuse block system also functions as the voltage changeover system.  All you have to do is to remove the fuse block, change the fuses to the proper amperage and then turn the fuse block over and reinsert it.

    Q: Will the KPA500 work with my KX3 and KXPA100?

    A: Yes, it can.  You can drive the KPA500 to full output with the KX3/KXPA100 combo. All the cables you'll need are in the KPA500 box assuming you're using the KXPACBL cable kit between the KX3 and KXPA100.

    Q: Is it possible to use a KX3 or KX2 directly with the KPA500?

    A: Yes, the KX3 and KX2 will drive the KPA500 to 220 watts (KX3 @ 15 watts) or 180 watts (KX2).  Please contact for details and cabling requirements.

    Q: What cables come in the box with the KPA500?

    A: You will receive an AC cable that you specify when you order.   There is a USB-to-RS232 cable that will allow you to connect the KPA500 Utility, running on your computer, to the KPA500.   Lastly, there is an RCA plug-to-RCA plug cable provided that will connect many non-Elecraft radios for keying.

    KPA500/KAT500 Power Combo (Choose One Power Cable at No Charge) Quantity Price
    PWRCOMBO-F KPA500 & KAT500 Power Combo, Assembled NOTE: Select 1 PWR Cable Below $2,849.90 $2,924.90
    PWRCOMBO-K KPA500 & KAT500 Power Combo, Kit NOTE: Select 1 PWR Cable Below $2,609.90 $2,684.90
    PWR-VKZL Australian Power Cord W/ Fuses $0.00
    PWR-US240 US 240V Power Cord Exchange $0.00
    PWR-EU2P IEC-European (Schuko) Power Cord w/fuses $0.00
    PWR-US IEC 120V U.S Power Cord w/fuses $0.00

    Our Amps Play Well With Others PowerCombo & Cable Packages Quantity Price
    KENPWRCMB-F PowerCombo Factory Assembled, Includes Kenwood cable, CBL-KENKEY $2,889.85 $2,964.85
    KENPWRCMB-K PowerCombo Kit, Includes Kenwood cable, CBL-KENKEY $2,649.85 $2,724.85
    KEN480PWRCMB-F PowerCombo Factory Assembled, Includes Kenwood cable CBL-KENKEY480 $2,889.85 $2,964.85
    KEN480PWRCMB-K PowerCombo Kit, Includes Kenwood cable CBL-KENKEY480 $2,649.85 $2,724.85
    IC7XPWRCMB-F PowerCombo, Factory Assembled, Includes Icom cable $2,889.85 $2,964.85
    IC7XPWRCMB-K PowerCombo, Kit, Includes Icom cable ICOMKEY706 $2,649.85 $2,724.85
    ICPWRCMB-F PowerCombo Factory Assembled, includes Icom cable CBL-ICOMKEY $2,889.85 $2,964.85
    ICPWRCMB-K PowerCombo Kit, includes Icom cable CBL-ICOMKEY $2,649.00 $2,724.00
    FLXPWRCMB-F PowerCombo Factory Assembled, includes FLEX cable CBL-FLEXKEY $2,889.85 $2,964.85
    FLXPWRCMB-K PowerCombo Kit, includes FLEX cable CBL-FLEXKEY $2,649.85 $2,724.85
    YAEPWRCMB-F PowerCombo Factory Assem., includes Yaesu cable CBL-YAESUKEY $2,889.85 $2,964.85
    YAEPWRCMB-K PowerCombo Kit, includes Yaesu cable CBL-YAESUKEY $2,649.85 $2,724.85

    KPA500 (Choose One Power Cable at No Charge) Quantity Price
    KPA500-K KPA500 500w Amplifier, Kit NOTE: Select 1 PWR Cable Below $2,074.95 $2,099.95
    KPA500-F KPA500 500w Amplifier, Assembled NOTE: Select 1 PWR Cable Below $2,274.95 $2,299.95
    PWR-US IEC 120V U.S Power Cord w/fuses $0.00
    PWR-EU2P IEC-European (Schuko) Power Cord w/fuses $0.00
    PWR-US240 US 240V Power Cord Exchange $0.00
    PWR-VKZL Australian Power Cord W/ Fuses $0.00

    Cables & Power Cords Quantity Price
    PWR-USa Extra IEC 120V U.S Power Cord w/fuses $19.95
    PWR-US240a Extra US 240V Power Cord $19.95
    PWR-EU2Pa Extra IEC-European (Schuko) Power Cord w/fuses $19.95
    PWR-VKZLa Extra IEC-Australian Power Cord w/Fuses $19.95
    KPAK3AUX AUX Cable Set Optional KPA500 or KPA1500 to K3S/K3 $35.95
    KUSB KUSB Serial Adapter Cable $42.95
    KXUSBa Extra Cable - USB RS232 to 3.5mm Cable $39.95
    CBL- KENKEY CBL-KENKEY Kenwood Keying Cable $49.99
    CBL- KENKEY480 CBL-KENKEY480 Cable for Kenwood $49.99
    CBL- YAESUKEY CBL-YAESUKEY Yaesu Keying Cable $49.99
    CBL36UHF 36" Coax Cable with PL-259s $26.95
    CBL - FLEXKEY CBL-FLEXKEY Flex Keying Cable $49.95
    E980190 DB15 Y-Cable $15.95
    E850463 KAT500 to K3S/K3 Enhanced Mode Cable $29.95

    Books Quantity Price
    E740244 KPA500/KAT500 book from Fred Cady $39.00

    Compatible Products