| W2NER |
Rating:  |
2023-08-28 | |
| Better than expected! |
Time Owned: 0 to 3 months. |
I have had many many amplifiers and my goto amp was a Acom 2000A which I sold recently. I have been a Acom guy for years. If you thing is tube amps, Acom is the one to go to. I'm getting old and I wanted to get something that would be easy to move around in the event my wife had to. At one time I had a Elecraft KPA500 which was bulletproof and was a great amp. So, I gave a KPA1500 a try, and I'm glad I did. It's wonderful, and the auto tuner is fantastic bar none! I have been so impressed by the workmanship I have gone all Elecraft! I purchased a KPA1500 a few weeks ago and it's been flawless. I can run it with 20w and see, 1300 watts with no problem. So, if you can swing the cost, get it, you wont be sorry. Yes they had some issues with the firmware early on but, that's been all ironed out. A++++. Sorry Acom, I've been converted, hihi! Oh, I have seen many say the fans are noisy, well I can agree with that to a point. But, I fixed that by replacing the fans and changing the mounting system. The mounting is done with rubber standoff's now, like many fans are done. Between the fan replacement and mounting system change, you can hardly hear them. Now if your into contesting and the fans run at high speed to cool the very high temps, yes, you're going to hear them. No getting around that, but, it is a massive improvement now with my mods.
As far as the power supply making any noise, that has to be an anomaly because you do not know it's even powered on in my shack. If you do a lot of digital work and push the amp it limits, you have to keep an eye on your temps. I don't do much digital work at all so, no data on performance with this mod.
Mod installation:
I don’t have instructions but I have some pics. It’s not that hard, the hardest thing was drilling out the holes where the pressed in nuts are. Getting them out is easy, put one of the fan screws back in part way and tap it with a hammer, come right off. Then after all of them re out, you need to drill out the holes large enough for the rubber fan mounts (not to big, step one size at a time till the rubber mount goes in snug). I think mine ended up being a .197 dia drill but, I’m not positive. Mount all the rubber mounts on the fans, then install the fans on the 1500. You have to cut and splice in each fan, you can trace each wire back to where it’s soldered on the power supply but, for ease of installation, I decided not to do that. Below are the parts and legal stuff.
I take no responsibility for any damage you or this modification may cause.
Fans
https://www.ebay.com/itm/303103688139
Mounts
https://www.amazon.com/gp/product/B01M4LVBY2/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
install Videos
https://www.youtube.com/watch?v=wykqVTTvrUI
https://www.youtube.com/shorts/DNwfdbBOW1c |
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| NR9V |
Rating: |
2023-08-07 | |
| Great amp but not perfect |
Time Owned: 6 to 12 months. |
Great amp, very nice front-panel layout & UI, easy to set up, small footprint. I ended up trading 'down' to an SPE Expert 1.5K-FA however which I like better yet cost ~$1500 less. Both work flawlessly with my TS-890.
The SPE is lighter, quieter, less fan noise and supports 2 ins 4 outs and SO2R. I used to have the 1K-FA about 5 years ago which was not as nice, the 1.5K-FA is a definite step up.
I should also note a small issue - the KPA power supply makes a quiet buzzing noise when the amp is off which is annoying and requires both the amp and the power supply to be separately turned on & off if you don't want a constant quiet buzz in the shack. |
|
| N4APG |
Rating: |
2023-06-04 | |
| Excellent Performance on MARS/GOV Frequencies |
Time Owned: 3 to 6 months. |
I am very pleased with my new Elecraft KPA1500 amplifier. The amp has abundant overhead, even on MARS/Government frequencies. Once trained to the frequency of use, the tuner is extremely fast and capable. This amp can easily meet government standards for ALE operation and tuning.
The connection to my Yaesu FTDX101MP is straightforward with the Elecraft interface cable.
This is not an inexpensive amplifier, but worth every penny if you need an amp for MARS and Amateur Radio use. Elecraft has gone beyond in making this amp useful in MARS. |
|
| W2LEW |
Rating: |
2023-04-02 | |
| Very Pleased |
Time Owned: 0 to 3 months. |
| Well I have owned my KPA 1500 s/n 01257 for just about one Month, and I am here to share my opinion. The KPA replaced an Acom 2100 Tuber which has been 100% reliable. I decided to go 100% Solid State with the Elecraft. I have the KPA 1500 coupled to a Kenwood TS 890 via a Serial Cable to enable auto band switching which it does very well. I usually keep my power levels at a KW or less, but it's nice to have the Horsepower if needed. I believe the KPA is running dual BLF188XR finals which have plenty of headroom in the RF department. Even at sub Kilowatt levels the Fan kicks in shortly at stage 1 and is somewhat noisy, but at stage 4 it is deafening. The built in auto tuner works so well and fast that I sold my HF Auto as it was no longer needed. I noticed that most competitive Legal Limit amps are foreign built and I wanted a USA manufactured one to avoid shipping over the Pond if repairs or parts are needed. It was a big $$ investment, but I'm happy with the product. |
|
| K3MD |
Rating: |
2022-11-18 | |
| Great when working |
Time Owned: more than 12 months. |
After delaying purchasing one of these amplifiers 4 plus years, I found one for a very good price used. The seller had had the unit updated and tested before selling it. The unit puts out 1500 W effortlessly. I interfaced my unit with an IC-7610, and the amplifier tracks the exciter flawlessly. This is remarkable given my lack of IT skills. The fan is a bit noisy, but at least it prevents the power out from destroying the transistors on board. The built-in antenna tuner is totally remarkable... it will match 3/1 very easily. I have never seen an automatic antenna tuner with such an extensive matching range. It performs well in the CWT... the CQWW SSB is this weekend... we will see (unless it gets totally wiped out by the solar flare). This unit is a joy to operate, after using manually-tuned full-power linears for 50 years. On DXpeditions I used an Ameritron 500W transistor amp with an external manual tuner. No need for that... the KPA1500 tunes your 80/40 antenna very easily. I plan on sending in another review after pounding the unit in many HF/VHF contests later. At least I have no need to pay $750 to $1500 for a new old stock Eimac 4CX1000A tube for my Alpha 8410 linear. Good Eimac pulls are $900 at RF parts... I got my good pulls for $150 a few years ago.
I had a single final failure after about 5 months. It took 3 months to get repaired. The repaired unit worked, but the ci-v did not work. Reset my IC-7610 in the chance that it was at fault. Excited with 100w, both finals blew. Lost temper, sent it back. It was repaired on warranty, but only the RF unit was sent back. I guess this is my fault for describing the problem in a detailed letter included with the unit rather than going thru product service. Got power supply back, so far it has been working FB. I still keep my no-problem used KPA500 and Alpha 8410 for backup. I do not like losing a final in mid-contest, which often happens. Like losing your hospital's CT scanner and having to send cases out. |
|
| AA6VB |
Rating: |
2022-11-17 | |
| An Excellent Amplifier Despite Some Shortcomings. |
Time Owned: 6 to 12 months. |
When my main amplifier needed repair I finally put my KPA1500 into service. The raft of DXpeditions presented an excellent opportunity to run the KPA through its paces. Performance has been outstanding.
A simple 1/8” (3 mm) mono or stereo cable connection was all that was necessary to allow the amplifier to track band changes on my Icom exciter. Operation is smooth and seamless. It’s like having a 1.5 KW Transceiver.
The menu system is clear and very easy to navigate. You can access certain menus items (e.g. fan settings) even when the amp is transmitting. The build quality, fit and finish and ergonomics are all excellent. The RF deck is small and separate from the power supply so it takes up less space on the operating desk than many other amplifiers.
I have only used it a few weeks but it has been flawless on CW and SSB up to the legal limit and FT8 up to 800 watts (don’t feel the need to run more power even when conditions aren’t great).
Elecraft uses two BLF188XR LDMOS transistors each capable of between 1200 and 1400 watts (depending on frequency) at 50 volts so running the amp at 1500 watts leaves plenty of headroom. The use of two devices is, in my opinion, an advantage over some other amplifiers.
The amplifier remembers the antennas “per band”. The tuner, after being properly configured, remembers the tune required for each band segment and automatically switches to that match (without retuning).
In the interest of providing a meaningful review for those who are trying to choose between one amplifier or another I feel compelled to share the following comments:
The fans can be loud at setting “3” and above and positively deafening at the highest setting - “5”. The fan noise is much higher than any other solid state or tube amplifier I’ve ever owned and it’s not a close contest. Don’t take my word for it. Just listen to the YouTube videos posted by WX0V. I use a RadioSport Headset which is pretty effective at eliminating most ambient noise but the fan noise still comes through at the higher settings.
I also wish Elecraft had seen fit to (a) allow two inputs (like SPE, Flex, and Icom); and, (b) provide at least 3 and preferably 4 outputs. Sure, one could use outboard coaxial switches for the inputs and outputs but these external devices should not be required on a high end amplifier. In my opinion this is a major shortcoming of the amplifier and my reason (along with the fan noise) for rating the amplifier a “4” instead of a “5”. Otherwise, it’s a fabulous amplifier.
For anyone using one radio and only two antennas, or for someone who doesn’t mind extra devices (antenna and rig switches) in the shack this is a truly great amplifier (if fan noise is not a concern). The amplifier should meet or exceed expectations.
73,
Bob/AA6VB |
|
| AE6PP |
Rating: |
2022-06-09 | |
| Excellent |
Time Owned: more than 12 months. |
| How to describe my KPA1500 Amplifier? I would like to say: BEST EVER. I have been QRV since 1960 as OH1VR and owned few home made, Dentron, Kenwood, Acom etc. amp's. My KPA1500 arrived to Finland over a year ago and since it has used mainly remote. The tuner of the amplifier is incredible. For remote user the amplifier is easy and secure. I'm not a technical guy - I love to operate and finally I have something that runs smoothly with my Elecraft twins. Yes, one problem: the price. The government of Finland wanted me to pay extra 24 % as VAT. |
|
| KP4AA |
Rating: |
2022-02-11 | |
| Best Amplifier I’ve owned to date. |
Time Owned: more than 12 months. |
I bought my KPA1500 over a year ago as the second owner. My previous amp was the KPA500/ KAT500 which I bought new in around 2015 and never had any issues with.
The KPA1500 has been through numerous 48 hour contests and hasn’t hiccuped. I keep the RF deck and Power Supply right next to each other and intentionally have the fans set to level 1 for everyday operating and level 2 during contests via the menu options. Why even allow the amp to get warm enough for the fans to kick in? Heat is the enemy! I do not find the fan noise objectionable whatsoever but I also use headphones when operating.
I have no complaints at all about this amp. One thing I have found is that the protection circuitry is extremely good at finding intermittent antenna, cable and connector problems that I was unaware I even had. Every single time I’ve noticed intermittent high SWR (yellow or red) on the amp or it intermittently faulted out it wound up being either an elevated vertical radial on the ground or shorting out to a fence in the wind or a poorly installed connector or a bad cable. I wouldn’t have noticed many of these quick intermittent problems with a tube amp. The auto tuner is also very easy to train and is as good at matching as any auto tuner I have used.
I have the amp mated with the Elecraft K3S, Array Solutions remote antenna switching and the OM Band pass filters. All instantly switch during a band change. There is no option for operator error at KP4AA and it’s nice to chase new mults on other bands with a single push of a button and not worry about blowing something up. I will never get rid of my KPA1500 and I will never go back to a tube amp.
If I could add one improvement it would be to have the power supply on/off switch moved to the front of the power supply from the rear. It’s very important for me to isolate the power supply from the mains here on the island where voltage spikes often occur. Turning it off from the front instead of reaching behind the power supply would be nice. |
|
| AE5GG |
Rating: |
2022-01-26 | |
| Glad I bought it! |
Time Owned: more than 12 months. |
I purchased this amp in November 2020 and it arrived some time in December as I recall.
For Icom users, your CI-V setting of "auto" needs to change to "19,200" baud rate if you want the amp to change bands whenever the radio changes (*I use the IC-7851 so that setting for sure has to change.)
Other than that, it's easy to operate, I love that I can fire it up and not have to wait for the 3 minute warm up of my tube amp. It's very nice looking, doesn't take up much room.
I am keeping my Alpha 9500 as a backup - she's been a great amp and I would never let her go. Why do I keep it? I think tube amps are much more "fault tolerant" against the occasional operator errors than the solid state amps. That said, the trade off is that you can turn on the Elecraft KPA 1500 and you're ready to go. Also, if you're a MARS operator - no need for mods, as it supports all HF frequencies from 160m to 6m except the obvious 11m CB band.
All that said, am I glad I purchased it? After thoroughly researching it against several other solid state / tubeless amps for Amateur and MARS use, yes. The Elecraft 1500 remains the best among the rest. |
|
| NX7U |
Rating: |
2021-11-04 | |
| Flawless, no-brainer choice |
Time Owned: 6 to 12 months. |
Absolutely perfect.
I'm using it with a K3 so integration/interconnection is super-simple. I get 1500W output with around 30W drive. Much easier to use and move around than my old BTI LK-2000...plus it does 6 meters.
The protection circuits work (thank goodness), and the built-in tuner is a very nice feature that by itself is easily worth 1/3 of the price.
I've never gotten the heat sink temp over 70°C, even trying...and it's rated to 110°C. Thermals are not an issue.
It will dent your wallet, but you'll dent the pileups. |
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