Manager


Manager - NA4M
Manager Notes

Reviews For: Elecraft KPA-500

Category: Amplifiers: RF Power - HF & HF+6M

eMail Subscription

Registered users are allowed to subscribe to specific review topics and receive eMail notifications when new reviews are posted.
Review Summary For : Elecraft KPA-500
Reviews: 124MSRP: 1999.95 Kit Form
Description:
KPA-500 Solid State Amplifier 160-10M Plus 6M, Auto Band
Switching via RF sense or cable connection.
Product is in production
More Info: http://www.elecraft.com/
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
251244.9
K3SUI Rating: 2020-07-13
ONE OF THOSE THINGS THAT ARE WORTH THE MONEY Time Owned: more than 12 months.
I bought one of these several years ago and from getting it out of the box until I sold it, it was one of the best amps I have ever used in my 58 years of ham radio. Put out more than the 500 advertised ... no ALC is necessary. Only problem I had was with the KAT500. KAT would tune OK at low power but trip amp when high power was brought on-line. If I liked it so much why did I sell it ? To buy the KPA1500 amp. I kept my KPA500 for a year but could not watch it gathering dust. Great amp ... worth the money. 5 stars
G3RCE Rating: 2020-07-13
Very robust and reliable Time Owned: more than 12 months.
The combination of KPA500 and KAT500 is excellent.
I had a TR problem which was quickly identified by Elecraft Support at no cost to me.
With Elecraft you can't go wrong ????
K2HAT Rating: 2020-06-06
Great little amp, owned for almost 7 years. Time Owned: more than 12 months.
Awesome amp, especially when paired with the optional
KAT500 Automatic antenna tuner.

Have had this for getting close to 7 years now.

November 2013.

120 volts, no problem with using a normal outlet.

73 K2HAT Lee
WN4BXW Rating: 2020-06-06
Excellent Amp Time Owned: more than 12 months.
I use this amp most of the time . No tuning and Instant on Running FT8. have owned it fro 5 Years, never a problem !

AC4R
W4HWD Rating: 2020-03-28
Nice! Time Owned: 0 to 3 months.
This amplifier is just what I need to get that little extra to make myself heard during these rough band conditions. I bought it as the PowerCombo, along with the matching KAT500 tuner. Super compact, this amplifier will go where a tube amp (or the big clunky ALS-600 for that matter) won’t fit. Setup was simple and I was on the air 10 minutes after I put it on the desk. Output is an easy 500w PEP on SSB, CW and FT8. The fan never comes on using SSB, only intermittently on CW, and only just a little more often using FT8. When the fan does turn on it’s not at all loud. My amp is running on a dedicated 240v outlet and at high power voltage never sags below 64v. All parameters can be monitored easily and the computer interface (only connected when needed to change parameters or update firmware) sets up quick and smooth. This amp plays so smoothly and quietly with my Icom 718 that it’s like it’s not there - until stations on the 75 and 40m nets give me flattering signal reports! Very worth it.

Edited to add this: resistor R9 in the TR switch failed about 6 months in. I shipped the amp back to Elecraft and they repaired it under warranty - and it's been running flawlessly ever since. I firmly believe that the ALC overshoot from my Icom 718 is what damaged and eventually killed R9 - but now that I've replaced the 718 with an Elecraft K3s I have experienced *zero* problems and everything is silky smooth. Just be aware if you are driving this amplifier with any non-Elecraft rig that has known transmit overshoot problems be prepared to send your amp back for repair at some point - unless you possess the tools and skills to work on surface-mount components, in which case you can replace R9 yourself.
W2XS Rating: 2020-01-04
Seamless integration with the K3 Time Owned: 6 to 12 months.
I've had the KPA500/KAT500 for 1 year now. I use it with my K3 which is from 2007. Over the years, I have kept the K3 up-to-date with new synthesizers, a new DSP board, etc. (even a new K3S trim ring around the main tuning knob!).

With a 135-foot CF doublet, I can QSY instantly anywhere from 160m to 6m. The tuner remembers the settings, and the rig is ready to go at full power in a second or two. The full break-in QSK on CW is a joy to use. I had a small RF issue on 20m but some clamp-on ferrites on the coax cable between the amp and the rig, along with some improved grounding connections, tamed things down nicely.

The peak of cycle 25 will be here in July 2025 - not that far away! I am hoping that the high bands open up once again. In the meantime, I'll operate on the low bands with a 500 watt transceiver.
K6BRN Rating: 2019-12-30
Great combo with any radio Time Owned: more than 12 months.
I purchased the KPA-500 amp/KAT-500 tuner kits several years ago. Assembly was easy - just a LOT of screws in the KAT-500, whose assembly time took more time than the KPA-500 kit. Both kits are modular and simply plug, screw and bolt togerther with very little fuss. Both worked right off the bat and the wattmeters were right on as well, without adjustment.

Several years later, they both continue to work without drama or excess noise. The KPA-500 does emit a soft pinging sound -sometimes- as it heats up and cools down, likely from the big (bell-like) belleville washers holding the toroidal power transformer in place. But it's not an issue at all.

Running the amp off of 120 VAC has not been an issue either - I can easily get full output+ from the amp but usually operate in the 300-500W range on FT8 - a pretty demanding mode.

Since I'm lazy and like to spend my free time on specific projects, I ordered a set of interconnect cables between the KPA-500/KAT-500 and FT-991 and FTDX-3000, including Yaesu CAT control for band changes and had them shipped to QTH#2. Phil Parrish - W4AIN provided the cable sets and did a very professional job. Thanks Phil!

Overall, the KPA-500/KAT-500 combo is simply excellent, tolerates high duty cycle modes just fine and takes very little bench space.

I recommend it without reservation. And Phil as well!

Brian - K6BRN

W1UT Rating: 2019-12-29
Perfect Kit for Those Who Like Building Time Owned: 0 to 3 months.
I rarely, if ever, post a review of a product but this time I felt it would help someone looking to buy the KPA-500 as a kit. I purchased the combo kit which included the KPA-500 and the KAT-500 tuner. I first build the tuner which was a joy to build. The instructions are clear and easy to follow. Just make sure you have a static ground strap and an anti-static mat when assembling either the tuner or the amp. I did not have the anti-static mat so I made sure all of the pre-assembled electronic components always stayed on the provided ESD bags that the parts came in. I took my time to build both the amp and the tuner. The amp took quite a bit longer, but no more than a day of careful assembly to build. Both the amp and the tuner worked perfectly when first powered up. The amp replaces an old SB-200 tube amp and the tuner replaces an old MFJ tuner. Needless to say the space savings on my desk is significant.

I give the amp kit a great rating for the quality of the parts, the wonderful manual and of course the service Elecraft provides. Yes the amp and the tuner is expensive, but you will get a top quality product.
WA4JUK Rating: 2019-10-31
A terrific amplifier for solid operation. Time Owned: more than 12 months.
I have the KPA-500 matched up to an Elecraft K3S transceiver using all Elecraft cables. I also operate at and recommend 220 power. It is as smooth as silk. I really cannot find any problems with it. It will not allow you to make a mistake. I have worked thousands of stations on all bands. I can only speak for CW and SSB operation. I am totally satisfied with it.
K1BUK Rating: 2019-09-22
Good but problems Time Owned: more than 12 months.
I have a love/hate relationship with the KPA-500. I’m happy to report that I’m currently in the love mode. I ordered this amplifier in early 2017, when I wanted a power bump on 160 meters, especially. I drive the amp with a Kenwood TS590SG.

I ordered the amp factory built because I didn’t need another construction project. There was a minor manufacturing defect discovered about a month after I received the unit. One of the LEDs on the SWR indicator was flaky and would flicker and turn off when it should be on. I contacted customer service at Elecraft and was told that I could fix it myself or send the unit back to the factory. Since it was factory built, I sent it back—its first trip back across the continent. I was instructed to take out the power transformer to reduce shipping weight.

I got the unit back a few weeks later working perfectly, except that the creaking problem noted by many in their eham.net reviews had raised its ugly head. “Creak, Creak, Creak,” said the amp after running it on CW about 300-400 watts or on FT8 at any power. At that time I was running about 250 watts on 160 meters FT8, primarily, but it would creak at any power level and any mode. Craig, W6WL, told me that the problem was the Z bracket. He sent me a replacement Z bracket at zero cost, and I installed it per instructions provided. The creaks went away. Maybe it helped to torque down the screws quite tight.

Then, in early April 2018 I experienced an amplifier failure. The amplifier turned itself off while transmitting FT8 mode at 250W on the 160-meter band. The SWR indicator showed 1.2 at the time. The symptoms were that in standby mode (Yellow LED indicator ON), the signal from antenna made it to receiver, but in operate mode (Green LED ON) the received signal was attenuated by more than 25 dB. And, driving the amplifier with normal levels (15 W typical) did not give any RF output power. Took out the power transformer again and shipped the unit across the continent. The problem was a failed 10 Ohm resistor in the T/R switch. Elecraft acknowledged receipt of the unit on April 13 and service was complete on April 25. This was a reasonable turnaround time. The only downside of this repair was that the creak came back with the repaired unit. At this writing the amplifier still creaks but it’s not as loud as in the past.

I am disappointed that a factory built amplifier would have so many problems. I think that the weakest points with the KPA-500 were quality control and thermal design. Were I buy another amp I would check other brands before spending the money. I am very pleased with the performance of the KPA-500, however. It moves from band to band seamlessly, interfaces cleanly with the Kenwood transceiver and provides that extra punch on SSB or CW. It is a very attractive unit in many ways and I’m pleased that so many others have rated it highly. Customer service has been quick and helpful.

I'd like to give it a 5 but for me the KPA-500 is a 3.