HR2.0 - RF-Kit RF2K-S Amp - Ham Radio Amplifier, Legal Limit, Hamvention 2022

I'm probably doing homebrew if I go solid state.

The mercury will fit my needs, but I'd like more headroom. As an AM operator dissipation is king.

I'm looking at doing a pair of 1.8k devices and a dupkexer for output filtering. Wrapped with predistortion.

Or the rf kit.

The wallet hasn't been pulled out yet. I have enough amplification now that buying a new amp is secondary.

--Shane
WP2ASS / ex KD6VXI

 

Suggest for AM to use a class D transmitter f.. like the K7DYY, super senior. I like it a lot. Near legal limit ... super compact...

 

I have many class E rf decks and a home dew PWM of my own design, but based upon some of WA1QIX and other people's earlier stuff.

I've also got a positive peak stretcher that allows for 100 pct symettey to 420 percent positive peaks (sounds great if the other guy has a sync detector, otherwise....... Not so much).

All of that equipment is in storage stateside now. So looking to get something to kick my Kenwood TS850 closer to legal limit.

I can hear the east coast gangsters down here, but 25 watts ain't gonna get me heard. At all. Ever. Not even with a tailwind!

--Shane
WP2ASS / ex KD6VXI

 

Sorry for the typos. This new Galaxy phone keyboard isn't very intuitive.

--Shane
WP2ASS / ex KD6VXI

 

Don’t worry. You’re Q5 copy here ! latest

So .. the prices:

Mercury 3 Assembled. $2800 (single LDMOS, near legal limit @1200W PEP max)

Mercury AT $800 (for antenna tuning as in the RF Kits RF2KS)

Ameritron QSK5 $600 (for full break in CW as in the RF Kits RF2KS)

Shipping fees $100

State Sales tax (7%) $300

Grand Total cost $4600 !!

Comparatively, the RF2KS seems like a bargain of the day at just $4999 with dual devices, much more output ! Even with the new price of $5500, it seems to be good bargain.

 

1500 watts is 2S units louder than a 100 watt rig through
any antenna

 

65 Postings(comments) on a simple video made during the HAMVENTION 2022 at Dayton... woowww. !!!

As you may know, the HAMVENTION took place in Friedrichshafen Germany last week. where Reinhard once again showed and demonstrated his RF2K-S similar to Dayton's. Reading all the comments and especially negative comments from people who don't even own this amplifier, it irritates me immensely. I've seen comments regarding Dutycyclce, the type of LDMOS being used or even OEM comparisons. So for some of these I can only say do me a favor and get a life or try another hobby... because when it comes to price, efficiency, Duty cycle, IMD (no one seems to care), noise, quality , Service, etc... Here comes my 2 EURO CENTS !!!

I've been indebted to tube amps and SS amps for nearly 2 decades. After owning Ameritron 811, ACOM 2000A, OM Power 2000A+ over 1 decade of owning SPE amps (1k- 1.3K FA-AT(V1) - 1.5K FA (V1) - 1.5K FA(V2)) can i say what a great product that SPE made at the time. But I also know that technology is changing. In 2019 I came across Reinhard and RF-KIT amplifier at the HAMVENTION in Friedrichshafen.
After consultation with Reinhard and my friends back in the lab in the Netherlands, I was sold.
At that time (2019) I owned 2x SPE Expert 1.5k FAs and already had an oscillating and noise problem with my version 2 model which SPE in Rome solved in the first week of ownership. So all the more reason to investigate what else is on the market....
Not much later, the RF2K+ (now obsolete) model was purchased and put to the test. One word BRILLIANT...!!!

The RF-KIT amplifier was and is to date the quietest High power amplifier on the market. I was so impressed with the silence and temperature handling at Full Duty cycle (never higher than 55C/131F) that I sometimes thought;
"... Am I really transmitting...".
Other aspects were of course plenty of headroom as this RF2K+ came with 2x BLF189XRA (each rated for 1.7KW) which gives a very clean signal. Following clean signal/IMD, people nowadays don't seem to care as long as they're heard, whether they're splattering all over the band, a real shame in my opinion. When the RF-KIT RF2K+ came on the market (RF2K-S is its successor) it came more like a KIT. The amp had an Arduino built in, fans had to be installed, coax jumpers had to be cut to length and re-soldered, and a Rasberry PI 3+ had to be bought and installed within the amp. So in addition to all the trimmer adjustments, it would take you at least 3+ hours to build and set up the amp. Oh yes.... this "+" model came with mechanical relay switching.

But after getting this RF2K+ and still owning my version 2 SPE 1.5K-FA, the decision was made quickly, especially after multiple A/B comparisons on performance, noise, duty cycle, etc...
At that time, Reinhard introduced an upgrade for the RF2K+ owner, as he had just started the rollout of his new RF2K-S. This upgrade for the "+" model included a PCB on the hardware controller board that allows RF2K+ owners to take advantage of future firmware upgrades similar to the RF2K-S model. Since I had already bought a new RF2K-S version, I decided to sell my RF2K+, not go for the upgrad board and just buy a second RF2K-S amplifier. The differences between the + and the S versions are Mechanical relay vs PIN Diode / Arduino vs CPU embedded / Rasbery PI3+ vs Rasberry PI 4 / BLF 189XRA (older RF2K+ can BLF 188) vs BLF 189XRB and no longer solder coax jumpers, Install fans and more which reduce the built-off with at least 2 hours.

Conclusion and yes you can say I'm biased (trust me I'm not). This RF2K-S amplifier is a truly advanced and quietest High power amplifier on the market. No other amplifier, including the KPA-1500 or even the PGXL, can't handle the temperature as RF-KIT seems to have solved. The heat dispensation of the RF-KIT is not only transferred by 5 Fans or the BIG Aluminum block, but also by the 1/2 Inch thick copper plate between the ALU block and the PA pallet board. Also in price and being FCC approved for over 1+ years, this RF2K-S is about 30% cheaper than its competitors and completely built, sealed and delivered in the USA. Also the service and support by Reinhard himself or John from Island Amplifier in the US is beyond anything you can dream of. Nowadays and practical examples of what is happening at SPE Europe, that the lead time of repairing LDMOS or any other problem can be between 3 -6+ months. Also if you want to request the status or something else then EMAIL is the only way to communicate. With RF-KIT just a simple phone call/skype, even after office hours, and they will support and assist you in any way they can. Well done RF-KIT and team !!

So if you are doubting, if you are not believing all what has been mentioned. No worries, just dream on ... and do what ever you think is good for you ;-)

I have no commercial interest witin RF-KIT Company, but credits to thosewho deserve it !

73 Roberto"Bob" PB5X
www.pb5x.com
PB5X Roberto - Hamradio Station from the Netherlands

PS: More info on amplifier & Clean signal
RF-KIT RF2K-S - PB5X Roberto
RF-KIT RF2K+ - PB5X Roberto
SPE Expert - PB5X Roberto
How clean is your signal... ? - PB5X Roberto

 

Check your antenna . Flat SWR should not cause any problems...

 

Great INFO
Thanks

 

Not seeing how SWR has to do with taking out his neighbors.

My 160 dipole has horrid swr on many bands, but I don't have any issues with neighbors, even running it on the other bands.


--Shane
WP2ASS / ex KD6VXI

 

2 S units is big sometimes, many people have S9 noise at their QTH and you have to be 10 over 9 for them to just hear you!

 

Not everyone needs or wants (all that much) full QSK. I used to operate a lot of CW but found it more distracting than useful. And I'd rather have an external tuner anyway. But the point is valid - for someone who wants those things.

 

Yes and no. There are theoretical S units and then real world ones. While we've all read that one S unit is 3 db, most rigs seem calibrated with an S unit being a good deal less than a 3 db difference. Then there's the fact that 2 S units, theoretical or actual, can be the difference between making a contact or not, or between armchair copy and barely able to pull you out of the noise.

 

Its a freeking Hobby,what we talk about isnt that important to anybody. On the ragged edge S1 or no needle movement 1500 watts can make a difference if the audio
was setup right.
100-1500 watts is 2S units on a calibrated meter, thats a fact. You can have your own opinions but not facts.
I think the Legal Limit and over amp crowd are using them as a crutch or a pacifier. Yes, I have a few amps that work quite well, I even turn them on once in a while.

 

"It's a freaking hobby?" Wow. Over-react much?

Most modern rigs from the factory do not have S meters calibrated at the "book" standard. And yes I should have said 6 db that "we've all read." Most seem to actually be closer to 3db thus my typo. But maybe yours is 6db. Or 60 db. I don't really care. The point is that an amp often makes much more difference than one would think based just on db calculations. I've used them off and on for some 40 years and that's been my experience - not opinion, experience. Yours may, of course, differ.