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Reviews Categories | Amplifiers: RF Power - HF & HF+6M | OM 2500 A Help


Reviews Summary for OM 2500 A
OM 2500 A Reviews: 9 Average rating: 5.0/5 MSRP: $4,000.00 EU
Description: HF auto tune amplifier
Product is in production.
More info: http://www.om-power.com/
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W5IP Rating: 5/5 May 2, 2016 14:54 Send this review to a friend
Powerful, smart amp  Time owned: 0 to 3 months
I considered several amplifiers before buying the OM2500A with the FU728F tube from Array Systems. Jay, David and Jim at Array Systems are great with their customers. I have had the amp over two months.

Like others, I was concerned about the cost of the final tubes in amps like the ACOM and Alpha. I wanted an easy legal limit so it would likely outlast me. I already have a Yaesu Quadra and had an aging Alpha 87A, since sold. I wanted quick auto-tuning. I wanted a hefty power supply. I looked pretty hard at a solid state amp that has strong features, but didn’t like some of the info I was getting on signal quality issues and it wasn’t available for delivery for some time anyway.

The OM2500A is delivered on a wooden pallet and is a pallet full of amplifier. It is shipped, transformers in place, ready to plug in to single phase 220 volts, but it better be a stiff circuit. After unpacking and a two-person lift to the operating table, it worked immediately on manual mode, but had difficulty reading the CAT commands from my FTDX9000D. I spoke with Jay at Array Systems who immediately corresponded with Tibi at the manufacturer. While they offered good and multiple recommendations, I found the problem to be in the setup of the radio. In the Yaesu radios, the CATTOT needs to be greater than 1000. Default is 10. When the radio was set right, the amp responded immediately at 19200 baud and now doesn’t miss a beat, tracking the radio precisely.

This is an extremely high-quality, well-built piece of gear and the cost reflects it. It is 92 pounds of instant QSY from 160-10. It does not, like the Quadra, cover 6 meters. It will handle 1500 watts of RTTY and the blower air is only warm. The signal reports have been outstanding.
The operator must pre-tune the band segments, but once done, the amp returns exactly right, immediately. The amp requires as little as 22 watts to drive 1500 and never more than 35.

The remote control unit does put the Operate/Standby switch close to hand and you can see the LED readout from a different view. There are other functions, but, I guess, as an old school type, I like seeing the amp. The fan creates a bit less noise than the 87A. Not silent or as quiet as the Quadra, but not bad and not audible over the PR781 microphone nearby.

Array Systems has announced a two-holer version of this amp, the OM4000A. The 2500A might do 3 KW. I would think, for the two-holer, a three-phase 220 volt circuitry would be wise, though I haven’t seen any info on it. Array Systems also has a new 3.5 KW auto-tuner, the DU3500AL from DU8HA. I bought one and it mates beautifully with the OM2500A-F, tuning everything in advance by tracking the CAT in the transceiver. I will review it separately.

In conclusion, a Japanese transceiver connected to a Texas distributor-provided Hungarian tuner and a Slovakian amp with a Chinese tube feeding a Missouri(PRO-96) antenna works quite well in New Mexico.
 
WA2TLY Rating: 5/5 Dec 31, 2015 09:03 Send this review to a friend
Very good power amp  Time owned: 0 to 3 months
I have been in ham radio a long time but out of it for 20+ years. This is the first power amp I have ever owned. I was originally intending to purchase the A2000 but Jay at Array Solutions directed me at the OM2500A. Jay and his crew handled all of the connection wiring for my ICOM7851. They also installed the 220V plug and wire as well as fully tested it before shipping. It arrived on a wooden pallet weighing over 100 lbs. Once opened everything inside appeared to be undamaged although the outer box was a little beat up. Two man carry up to the 2nd floor and into the shack. The manual gives the most minimal amount of information and should really be expanded and improved. I wasn't sure where some of the connecting wires went and had to call Jay who responded immediatly. The amp worked immediatly as expected and the auto tune feature worked although I am not sure how accurate it stores the tuning values because I frequently will fine tune it after a signifcant frequency change. I chose the chinese made FU tube at Jay's suggestion - a little less expensive and in active production. The fan noise is noticeable but not intolerable as I had the amp right next to me. When I raised it up some so that the fan was above my line of sight much less noticeable but not totally silent either. When I do something stupid the protection circuitry seems excellent. There is about a 3 minute warm up delay and I can put out 1.5kw cw key down signal all day with no effort- maybe 30 watts to drive it. I suspect it would handle 2 or 2.5 kw as well but no reason to run that kind of power. The front leds show power out and reflected power and grid current. If reflected power exceeds about 300 watts the amp will automatically shut down. I have used it on 40m thru 10m but not on 80 or 6 yet.
I cannot comment on longevity yet and I think I still have more to learn about how the amp operates- a better written and more thorough manual would have been helpful. Support from Jay and his crew at Array Solutions anytime I had a problem was quick and easy. I did buy the remote but I don't see much use for it the way I am operating.
I would actually like to give this amplifier a 4.9 due to the lack of a good manual otherwise seems very solidly built and excellent backup by Array Solutions.
Larry Plumb WA2TLY
 
W7ZR Rating: 5/5 May 3, 2015 15:33 Send this review to a friend
Like A Rock  Time owned: 0 to 3 months
I don’t like to review a product before I have used it for at least a few months. Therefore, this will be a “preliminary” report. I have had the OM2500A for one month now. I have operated two contests with the amp with zero problems. So here goes:

The Good: Like I wrote, no problems. 25-30w drive produces full legal output after a little mod that is reversible. However, stock is just fine. Automatic band switching works well. The tuning for the new band does not change instantly but requires a dit or a cough. Once the used band segments are memorized there is very little to do. Hookup is straight forward but more on that below. Delivery from Array Solutions was fantastic. Arrived in 2 days via common carrier from Texas to remote Arizona. Delivered on a pallet and into my garage and from there a hand truck got it into the shack for unpacking. I did have my Wheaties that morning so hefting it onto the operating desk was not a problem with the nice handles on the side of cabinet.

The Not So Good: Documentation is skimpy and in places confusing. No schematics. Lots of documentation for most brand of transceiver but not Kenwood. I have a 990 but no problem. Noise…everyone seems to be concerned about the noise. It really is not so bad. My OM sits 3 feet from my op chair. The rig does keep my shack toasty but won’t be so bad in the winter. In my opinion the remote is a waste of time and money. I can’t imagine not having the amp close by for tuning or better monitoring. The remote monitors output power with a bar graph and some LEDs for fault monitoring. The ACOM 2000A remote is more functional. I really do not see how you can run this amp remote. But I could be proven wrong. Waiting on some comments on that.

Wishes: USB port to computer. Better soundproofing starting with tube fan. Better documentation. More functional remote.

Overall: Would I do it again? Absolutely. I will attempt to update this after some more time. Thanks again to Array Solutions.
 
N2YPD Rating: 5/5 Feb 28, 2015 02:44 Send this review to a friend
BEST AMP I'VE EVER OWNED  Time owned: 0 to 3 months
It is very heavy but with reasons. I have many amps in my shack,(ALPHA 9500, QROHF 2500DX, COMMANDER 2500DX, KENWOOD TL 922, ICOM IC-PW1, TOKYO HY-POWER HL-1.5, HEATHKIT SB220, QRO HF 2000) but no other amp like this one, it is expencive but i am glad i spent my money on it It is very easy to use, The build quality is second to none, only the best materials are used and the finish is fantastic. Another big plus is even after hours of use the OM2500A stays cool . It is automatic in the truest since of the word. QSY is nearly instant. Full power + . I have to monitor output constantly to stay under the 1500 watts limit. I give The OM2500A a 5.5 rating for being built like a tank, Easy operation, and with good operation practice it will last a lifetime.. All I can say is the Amp works exactly like it should. The amp has been flawless in it's performance. Yes, this is a big investment but you get what you pay for and the OM2500A This Is a Real Gem of and amplifier. absolutely brilliant. have no regrets buying this amp and can highly recommend it to anyone looking for a top tier contesting amplifier.
 
M0ZMX Rating: 5/5 Feb 27, 2015 13:10 Send this review to a friend
Effortless power  Time owned: 0 to 3 months
I saw this amplifier at a very good friends shack, I was blown away by its effortless power, no clunk, no hum, no pitch change, this amplifier just delivers without issue. It Follows the radio, shares its rs-232 without issue. I have this amplifier connected with a K3 and a steppIR and all works seamlessly. If it wasn't for the power meter bouncing one could be forgiven for thinking that it just wasn't working, it's really that effortless. I have the 3500A remote unit as the 2500A remote just went over scale,, running on a single phase doesn't stop this amp producing in excess of 2500W.
The amp requires but a sniff of rf and the stepper motors tune the amp in a second. It makes my previous automatic amp (Expert 1k-fa) seem silly by comparison, a heavy and substantial piece of kit, you know when you carry this puppy to the shack!!!
The build quality is exceptional, a real 'Belt and Braces unit'

I purchased this through Vine Antennas and it arrived promptly in perfect condition. great amp, great supplier.



Would I buy again ? "Without a doubt"

A true 5 out of 5
 
KW4CQ Rating: 5/5 Feb 26, 2015 11:30 Send this review to a friend
Beautifully crafted amplifier  Time owned: 0 to 3 months
I contacted Array Solutions in Texas and ordered one of the OM2500A HF linear amplifiers manufactured by OM Power, headquartered in Slovakia. They have been manufacturing top of the line amps for over ten years and are suppliers to many of DXpeditions. The amplifier arrived in perfect condition three days later by truck freight mounted on a wood pallet. While I have only had the amp on the air two days now, some of my preliminary thoughts might be of interest to other's contemplating a similar purchase. In three months I will post a more to-the-point technical review of my experience with this beautiful piece of gear. The OM2500A comes double boxed and at 90 plus pounds requires two people to lift it onto my operating desk. It came wired for 240VAC service with a 3-prong NEMA plug attached to the power cord. I am using the amp with my Yaesu FTDX-5000. To get up and running with the amp you will need just one RS-232 serial cable from the back of the transceiver to the amp. This cable carries your radio's band switching data for the amp. Just go into your radio's menu and set the parameters given in the amp's user manual and your all set to fly. I gave the amp a legal limit shake down cruise using CW on all bands 10-160m and what a nice experience that was. In the Auto tune mode the amp senses the precise frequency of your transceiver and within a second or two tunes itself to that frequency ready for action. Alternatively, you can manually tune the amp by switching operation to the MAN mode on the front panel. 1500 watts is acheived with 50 watts drive from my Yaesu. The amp easily delivered 3 KW CW carrier into my dummy load. The Gu84B ceramic tetrode tube seems to be bullet proof and should last a very long time.
That'a all for now. More in 90 days.
 
M5LRO Rating: 5/5 Feb 26, 2014 00:11 Send this review to a friend
Supreme Build Quality that matches performance  Time owned: 3 to 6 months
Here is a product that does not come along all too often. The OM Power 2500A. This is a fully automated tube amplifier that works with most radios offering auto tune and instantaneous band changing capability.

I use this with my Hexbeam for 20-10 and a doublet for the low bands, when on the hex I can band swap ad lib and it just works, it will tune from 80m to 10 mtrs in a flash and your good to go. Makes assisted S & P a breeze, jumping from one band to another a peace of cake. Just click on the cluster with the mouse and the whole station just does a qsy, tunes and you then hit the key, what could be more simple.

The RF deck uses a very rugged and high gain Tetrode offering well in excess of its specified power output courtesy of the massive power supply built into the cabinet which in itself utilises two transformers. The unit is ideally fed with 2 separate phases but will function happily off one phase provided the cables are large enough to carry the current demand.

I have held back writing a review of this product for a while because of teething problems I had regarding communications with the RS232. I use the amplifier with a K3 and that caused some issues regarding coms but Tibi, the owner of OM Power, worked tirelessly on my behalf to improve the product and a new firmware chip to make it right.
Not once from the outset have I had an issue with the amplifier from a Power delivery aspect, in every possible way the PA is stunning, very good figures on the scope and NO RFI issues at all, even testing at high power.

This is quite simply a stunning product made by caring, courteous people, who really do consider the customer as king. Thank-you to Tibi and the guys at OM, I have a power house in the shack which I will never need to replace.

Do I recommend it, OH YES, and what's more with agents like Innovantennas in the UK and Array Solutions in the US, you know OM Power are well represented too.
 
PY2ADR Rating: 5/5 Feb 20, 2012 01:55 Send this review to a friend
Awesome  Time owned: 0 to 3 months
Fired up mine yesterday with my K3. Work´s just great and really automatic. Few issues in how to connect my P3 together. Anyway: strong, beatiful, well finished and of course lot´s of power. 2 kw easy on any band. Completely satisfied so far. 73´s PY2ADR / ZY2C / PR2X
 
NP2G Rating: 5/5 Jun 7, 2011 19:55 Send this review to a friend
Great Amp.  Time owned: 6 to 12 months
OM 2500 A
I was looking to replace my Alpha 87-A which has given me many pleasurable years of unflinching service and will probably give it’s new owner the same.

After looking carefully at the field of contenders I found what I was looking for in the OM-2500-A . Simply put this OM-2500-A amplifier is my old Alpha on steroids.

Look at photos of any serious contest station and most likely an OM or 2 or 3 will pop up.

Yes it will produce 3KW + and Yes it will do this all day long. Since it has a robust 4.5KW power supply there is loads of overhead available.

The GU-84-B tube with 2500 watt plate dissipation is a reasonably cost efficient, watt producing, valve. Being a tetrode it exhibits the nice gain characters of this species.

Another benefit, when it eventually comes time to re tube, there is only one tube to purchase .

EBC or Electronic Bias Control is fully functional with this amplifier. It allows for a nice watt saving shut off of between words or between CW characters without distortion.

Integration with the OM Auto amplifier is very easy. It will accept various rig’s CAT control via the RS 232 through put connections.

The addition of rotary knob adjustment’s (Tune /Load) vs. (Up / Down) selection switches are just a nice tactile advantage.

And the amp does work in Manual. The tuning procedure is straight forward and easily duplicated.

Metering is great. The simple addition, along with the normal (2)LED display, of the second Grid display meter ,is far superior to just having a LED light “ALMOST” or Red LED when it is over powered.
Why not display the real values rather than light and guess.

My intentions have always been to have amplifier that will last through the challenges of time. I believe that the OM-2500-A is the answer.

Would I recommend for anyone to purchase the OM-2500-A? Absolutely.

Is there a OM-3500-A in my plans? I guess you will just have to wait for the contest photos to come out.
Ed Baker NP2G
 


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