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Reviews For: RF-KIT RF2K-S

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

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Review Summary For : RF-KIT RF2K-S
Reviews: 19MSRP: $5000
The RF2K-S distributed is a fully solid state software defined amplifier running a pair of BLF-189XRB LDMOS finals. Features coverage of 6 to 160 meter operation, frequency sensed tuning, built-in ATU, PI-4 computer control for easy feature updates either via WiFi or Ethernet internet connections, Universal/CAT/UDP control from your rig or PC for amplifier control, four switchable antenna outputs with memories so you can have it switch to the proper antenna depending on the operational band, plus many other features.
Product is in production
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# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
NT8F Rating: 2023-09-16
Great piece of German Engineering. Time Owned: more than 12 months.
I’ve been using this amp for over a year now and really love the SS LDMOS it provides. Of all the amps I have had (Ameritron, QRO, OM, Elecraft and Acom} this one is at the top. It is the quietest amp and its size makes it easy to place where it needs to be in the shack. It loafs along 1K but will do 1.5K with ease. It has outstanding protection features that will keep the amp safe even when operator errors would cause other amps to have issues. The feature that I really like that I have found unique to the RF2K-S is its display. I will show the last peak power reading, reflected and SWR of your last transmission until you make your next transmission.
Customer support is outstanding and user input is welcome and taken into consideration for future update releases.
KB6HRT Rating: 2023-09-16
WINNER Time Owned: 0 to 3 months.
This baby has everything, what a dream 1500 watts + works in my setup, using a TS990s to drive it 30w drive
1200/1300w output on noise in the shack, takes about 5 sec to come on and load, am glad I weight to buy a good SS amp!.........73s..........kb6hrt..........WINNER
W9AC Rating: 2023-05-17
Solid Build Quality Time Owned: 3 to 6 months.
Time owned: 5 months.

My primary mode of operation is CW. The RF2K-S was designed with fast QSK operation in mind and to that design objective, it clearly delivers.

Compared with several other solid-state amps I've owned, the RF2K-S is significantly quieter: quiet QSK system and quiet high-volume, low-velocity cooling.

RF2K-S amp control in my shack is via WiFi over a TCI server connection. Set the TCI address in the radio control and VNC connection programs, and rig-to-amp tracking is fully automatic.
K9UR Rating: 2023-01-15
Superb amp for CW contesting. 1.5KW+ . QSK . ATU works well. Time Owned: 3 to 6 months.
Update: Ordered Second amp. Delivered 13 weeks from date of order. Second one working like a champ. One loose connector inside when it arrived, from shipping vibration. tightened SMA connector and all perfect.

This is hands down the best featured amp for a CW contester out there. Full break-in with PIN diodes. Whisper silent fans for cooling. Easy remote desktop control, UDP or CAT or TCP (wifi) even RF sense control, 4 antenna ports, antenna tuner built in. So good.

The Mercury Lux is left in the dust with this one...and the loud KPA1500 and Power Genius XL can't compete on price or silent operation.

Considered several LDMOS amplifiers including the new Mercury III and the Lux as well as Flex Power Genius, the Elecraft KPA1500 and the lower power Palstar LA1K. Have had ALS600 ameritron amps with QSK upgrades previously. 20 years, those were rock solid. Wanted full breakin with PIN diode switching, built in ATU, Super wisper quiet cooling Ability to run on 120V or 240V. Small size. Fully remote and radio controllable. Legal limit + ...

One word: Super. So good that ordered a second amplifier for my "studio b" location. How's that for satisfied customer and these aren't cheap. But it truly simplifies the shack.

No more watt meter (built in) no more tuner (built in) no more patch cables (integrated) no more need for extra computer (built in) and can be totally remote too!

I hear they use one of these in the Yukon at VY1AAA contest station! I can now understand why.

This amp is sensational. It's totally integrated with my Icom 7610 and is like having a legal limit radio. Simple as that. The tuner works into 3:1 VSWR very reliably. The amplifier can do 1900-2000w PEP output (CW) on 240VAC and at legal limit running contest mode you can hardly hear the fan noise.

Wait time as of August 2022 is 12 to 13 weeks...WELL worth the wait. Price is now $5500 shipped all-in.

I priced the mercury 3 first.

Amp: $2800
Shipping: $100
Tuner: $800
QSK box : $500
Shipping for tuner and QSK box: $50
Sales tax: $250
Total cost: $4500 and still only 1.2KW

For a few more bucks, I went with the RF2KS which is well integrated, and has dual LDMOS devices giving true full legal limit (and then some).

I looked at Elecraft KPA1500 but it sounded like a hoover vacuum cleaner when I saw at Dayton. I also checked Power Genius XL but he cost is too much. I also looked at older amplifier like the Icom PW-1 using older technology -- also good but only 1KW.

You can see performance in QSK here:

Running from 240V in my shack, the amp temp never rose above 43C; Contesting CW at legal limit.

So far, so good. This review will be updated as time passes and as the second amp arrives and I give them both hard workout !

W1SWL Rating: 2022-11-27
The Check "All Boxes" Amplifier Time Owned: 0 to 3 months.
The RF-Kit RF2K-S is NOT a kit. It comes fully assembled and ready to run. For me it checked all the boxes... So let's run down the list...

Very Fast RF Sensing for High Speed CW & QSK - YES
1500W full legal limit - YES
Excellent Signal Quality -55 dB output Predistortion - YES
Ability to Control/Monitor Amp via PC/MAC/Tablet/Cell Phone (Windows, Linux, Apple IOS, Android) for remote operation - YES
Ethernet cable /WiFi wireless - YES
One Enclosure 7.5" x 12.2" x 16.7" - 35 Pounds - YES
QST Magazine Review - YES (Nov. 2022)
Sleep Mode for Low Power Consumption - YES
Built in Antenna Tuner (ATU) for up to 3:1 SWR Match - YES
Memory Banks for ATU settings - YES (3 Banks)
Supports 16 External Antennas via Antenna Switches - YES
ATU Follows Real Time Transceiver Freq. - YES (CAT & UDP)
4 SO-239 Antenna Ports - YES
Automatic Antenna Selection based on Band - YES
Great Support - YES (and groups.IO forum)
CAT connectivity via USB - YES
CAT connectivity through IP (UDP) Lan or WiFI - YES
TCI interface for SunSDR - YES
UDP Control - YES
NodeRed Support - YES
Online Firmware Updates - YES
New Features/Functionality via Updates - YES
Quite Operation - YES (Very)
Customizable Color Display - YES (Bar Graph or Analog Cross Needle & Contest mode)
7 Inch Color Touch Screen Display - YES
Power Meter 1W through 3KW
External Power ON by applying +12V Thus Remote Operation - YES
Antenna Tuner usable stand alone - YES
90 to 290 Volt AC Single Phase - YES (power limited below 240V)
Product Warranty - YES (includes shipping)
Future Proofing Board Upgrades Available - YES (Historically)

Am I happy with it - YES

N4EFS Rating: 2022-10-13
I Like It! Time Owned: 0 to 3 months.
I received the RF2K-S six weeks ago.

So far, the RF2K-S has performed flawlessly on all covered bands using CW, SSB, and FT8 modes.

Initial setup was easy. Any questions I had were answered quickly.

The ATU works well. The only small issue was on 12m where it was necessary to manually adjust L & C to obtain the best match.

The amp follows frequency changes quickly using RF sensing, or UDP, or serial CAT / Icom CI-V (via FTDI USB cable).

There is not much to add beyond what others have posted. It seems to be a good quality and robust amplifier, and has been a pleasure to use.

Technical support is unusually responsive. The company owner, Reinhard (DH3NAB), can be contacted personally at any time by phone, Skype, or email.

The product warranty provides for shipping in both directions should it be necessary to return the unit for repair.
K8AC Rating: 2022-10-09
They're not all perfect Time Owned: 0 to 3 months.
This is a factual review reflecting my recent experience with a new RFK2-S amplifier after a 12 week wait between order and delivery. This isn’t my first amplifier - I’ve owned 17 over the past 54 years. When I unpacked the amplifier, one of the long screws securing the fan fell out. Of the four screws that should be holding the cabinet shell to the unit, the two on one side had never been installed. While testing the unit to make sure it could achieve rated output on all bands, output on 40M would not exceed 1,200 watts (other bands OK). During a Snipe video session with an RF-Kit representative, he had me test the output on 30M (30 and 40 share an LPF section) and at a low power level there was a brief flash and the muffled sound of a component failing.

Inspection of the LPF board revealed a surface mount capacitor had blown and scorched the board. The rep decided to send me a new LPF board from Germany and I had it in just four days. The new board was an improved design with larger surface mount capacitors. I began testing with the new board on 160M and before reaching rated output, again there was a flash and the sound of a component failing. Inspection of the board showed another surface mount capacitor had failed and scorched the board.

At that point, I had had enough of quality problems and requested a refund. Through all of this, the RF-Kit rep was courteous and helpful and his support efforts were far above what you could expect from most other manufacturers. Before ordering the amplifier, I read through all the posts on the forum for the amplifier and found no reports of problems and no negative opinions. When I encountered the loose/missing screw problem, I posted an item on the group about that. After a few days, my post disappeared from the forum.

So, that’s my experience. Ignoring the quality problems, the amp is a nice package, it’s light weight and the cooling fans are probably the quietest you’ll ever run across. It makes full output with between 25 and 45 watts input. The display is bright and readable. The manual is very detailed, but lacks high level descriptions of how to operate the device. If you have good technical skills and are comfortable replacing boards in a device, then this may be a good amp for you. Otherwise, you may be shipping your new amp off to California for repairs. Am I the only owner of this amp to experience quality problems? Maybe, but you won’t know for sure by reading their forum.

NY9H Rating: 2022-10-08
do yourself a favor : READ THE QST REVIEW Time Owned: more than 12 months.
WHILE MY AMP IS THE OLDER VERSION, I am reluctant to update it to the S version. The company already provided boards to upgrade the amp to run current & future software !!!! So the only thing lacking is pin diode switching... and my cw does not need that.

Ran with my K3 till I got K4, integrates well with both.

Love the 4 antenna memory tuner...

I still have my ACOM2000A ( 15 years old) which I also enjoy. However to get the REAL story, do get ahold of the NOV review in QST magazine...low distortion--very quiet...
bill ny9h/3
VY1JA Rating: 2022-09-04
Excellent Amp and Stellar Support Time Owned: 3 to 6 months.
The RF-Kit RF2k-S (2k for this review) only available now fully assembled, is the best radio purchase I have ever made not just for the quality of the amp itself, but also for the sales support given by John at Island Amplifier.
The 2k is much more than an amplifier with a lot of headroom, It has built in automatic band antenna selection and memory antenna tuning. It can do these functions via Yaesu format BCH Antenna port, rig serial port, via built in frequency sensing or in our remote use, listens for frequency data on the LAN sent from N1MM. What ever you could want it is already built in. It takes less than 20 W to drive this amp to the full legal limit in Canada.
On the Sales and support side, John at Island Amplifier is very fast to respond and willing to do all he can to accommodate, both during and after the sale. His help has been super in getting the amp to do what we want it to do for our contest station at VY1AAA/VY1JA. So far the 2k has proven to be far and away a better amp and having better support than the Alpha 9500 it replaced
If you have any questions, feel free to contact me by mycall at arrl dot net.
N9WW Rating: 2022-09-03
Great Amp! Time Owned: more than 12 months.
I've had my RF-Kit for 2yrs. Paid $3200 delivered in kit form and it's been fantastic. It's quiet, robust and dependable. Reinhard has done a fantastic job. As far as the tuner in the RF-Kit amp, I never needed to use it because I have antennas that are resonant unlike some other hams that don't understand antenna theory. That said, I also have the Mercury IIIS. Another great amp. I will never part with either. It's great to see LDMOS amps making progress in the ham community.

73, Jim N9WW