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Reviews For: Mercury IIIS HF/6m amplifier

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

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Review Summary For : Mercury IIIS HF/6m amplifier
Reviews: 71MSRP: $2500/kit $2800/assembled
This solid state HF amplifier uses a single LDMOS for
fully automatic operation from 160m to 6M making 1200W with
input power between 50 and 90W depending on your ALC
setting. Protected against antenna SWR over 2 to 1 and
also against excessive input power. Builtin power supply
for 120 or 240 VAC without changing taps in the
transformer, just changing the power cable plug.
Fans work silent and color front panel display. Output to
three antennas selectable in the display with operator
Available as either a kit or starting in early 2022 factory assembled.
Product is in production
More Info:
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
N4TD Rating: 2022-04-08
Excellent Amplifier Time Owned: 6 to 12 months.
This amplifier gets two thumbs up. I have used it a lot on all bands and modes. On digital modes I usually operate with 500-700 Watts out with no issues. The Mercury IIIS looks great, operates perfectly, and has an excellent user interface.
AA4SS Rating: 2022-03-29
WOW !!!! Time Owned: 6 to 12 months.
All I can say is, I am so glad I got this Amp. I concur with all the other reviews so I'll not repeat them. You'll be happy when you get it.
W9KK Rating: 2022-03-14
FANTASTIC Time Owned: 0 to 3 months.
Several of my friends bought the Mercury 3 S, and they all raved about It. I finally bought one, and all I can say Is FANTASTIC! The AMP works on 110 or 220, just change the plug, same wattage, no re-duction. 5 stars all the way, nothing that I don't like, best bang for the buck! Auto Tuner coming In April!
KN1B Rating: 2022-03-07
AWESOME!!!! Time Owned: 0 to 3 months.
All I can say is I agree with everything positive posted. So worth the wait. No issues with assembly. Followed instruction to the "T". Powered up, tested, and operates just as it it should. Highly recommend the Mercury IIIs!
W4AEG Rating: 2022-02-06
Incredible amp and support Time Owned: 6 to 12 months.
I the dummy assembled it wrong. Sent it back to Kenny and he fixed no charge and refused to charge for repair and even for shipping back. Incredible service. Best amp on the market and service.
K0AID Rating: 2022-02-05
Exactly what I wanted in the shack Time Owned: 3 to 6 months.
This amp changes everything about operating an amplifier. Low noise, small space, automatic tuning, incredible self-protection, good looks and excellent support are the starters.

The amp was easy to build, took about 3 hours. Had a slight problem. Emailed KM3KM on a Sunday evening and had an email answer back that night and the small part I needed in the mail by Tuesday. Problem solved. But then KM3KM followed up with a phone call to me that Tuesday afternoon to make certain all was good. It was good, has been good and I think I'm going to enjoy owning this Mercury IIIS amplifier for a very long time.
K4ROX Rating: 2022-02-05
Best money spent in ham radio Time Owned: 0 to 3 months.
Now spoiled after bouncing from tubes. The design, quality build of the parts, and support are exceptional. Easy, fun build. Two months and several hundred QSO's later, I declare this amp a winner.
W8KMA Rating: 2022-01-21
Perfect!!! Time Owned: 0 to 3 months.
This amp is a winner!!! You put it together, it works and you enjoy it. Isn't America great!! If everything you buy works like this, life would be a much warmer fuzzy feeling!!
Seriously, the folks that designed this have all the bases covered!! I run 1100 watts most times and driving with 30. The high speed fan never comes on and it runs about 40c most the time if you chew a long time. Sounds like a computer running. Very quiet!! I happen to be running this on 120v with no problems. I plan to switch to 220 by only changing the cord. The power supply auto switches the voltage input. And that is just the tip of the iceberg!! The only thing that would be cool is if the amp read your transceiver power output in standby. But is that really necessary??.... The rest is smooth sailing!! Well worth the $$$$ if it goes 20 years like my old Ten Tec..HiHi!!!
W9BHI Rating: 2021-10-28
Best value for your money! Time Owned: 0 to 3 months.
I bought this amp from a fellow ham who decided he needed a new 432 Mhz amp more than this one.
He built it about 4 months ago.
I had to get a new .TFT file to replace the former owners call on the display and Kenny responded within a few hours and emailed me the new file.
How's that for service?
I use this amp everyday with my Anan 7000DLE and it works flawlessly.
It is super quiet, even with the fan on maximum speed.
I have it set to around 900 watts output on all bands except six meters.
The wait time for a new kit is around 4 months but if you want the best amp for your money, get one on order now.
AE5X Rating: 2021-10-22
Fantastic value Time Owned: 3 to 6 months.
As others have mentioned, the amp arrives in much less time than initially stated. Mine took about 2-1/2 months to arrive and 5 hours to assemble.

I bought this amp to replace my KPA-500 because I wanted more output from my IC-705 (10W rig) than the Elecraft could deliver. I use the Mercury on CW, phone and digital modes and power it with a dedicated 240VAC line. Here is the output with 10 watts drive:

10m - 240W
12m - 250W
15m - 250W
17m - 300W
20m - 400W
40m - 620W
80m - 670W
160 - 450W