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Reviews For: QRO HF2500DX

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

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Review Summary For : QRO HF2500DX
Reviews: 59MSRP: 4095.
Description:
Please go to http://www.qrotec.com/specs25.html
Product is not in production
More Info: http://www.qrotec.com/
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
00594.7
W5AAT Rating: 2013-05-03
I COULDN'T HELP MYSELF! Time Owned: more than 12 months.
If you already have one, why not get another one? A local friend of mine decided to get rid of his 2500 so I snagged it. I'm retired, so it was a simple matter to transfer this from the trunk of my car to the radio room while the XYL was dutifully at work. (Hey, ONE of us has to work, right?)
After my two young neighbors had wrestled it into place I turned it on. Yup. Just like it's brother sitting on the other side of the shack: 14w in = 1400w out. 20dB of gain. Just sitting there not even moving the screen current. Well this bad boy is only going to see duty on 40 and 75.
You know, maybe I should get another one. No. No reason to. The way these are built my grandson will probably be using them when he's my age.
73,
Todd / WA5XX

----------------------
Earlier 5-star review posted by W5AAT on 2012-07-08

Ray has put together a true "dreadnought" of the airwaves. It is big. It is bristling with firepower, ready to take on all comers on any band. In case you're waiting for the obvious, well here it is: YES! IT IS BUILT LIKE A BATTLESHIP! In fact, with it's haze grey cabinet and behemoth construction it belongs on a ship! This is one heavy dude and the performance is not for the faint of heart. I decided to buy one a few months ago after purchasing the 2000 from a friend of mine. I use that amp on 75m now. A great amp in it's own class. I called Ray and ordered the 2500. It arrived in 3 pkgs and approx 1/2 hour and a double hernia later I was ready to rock. 14w input on 20m resulted in approx 1300w output. I let it coast there for a few days. All I will say is that it is REAL easy to start knocking on that 2kw+ level if you don't keep an eye on things. It runs very cool and I may just sell my 2000 and buy another 2500. Well done,Ray. Very well done, indeed.
73, Todd / WA5XX
KY4RF Rating: 2012-11-16
great amp Time Owned: more than 12 months.
great amp,excellent preforemance and was quality built by ray.
WC3W Rating: 2012-09-20
This amp has been my best purchase ever since becoming a ham! Time Owned: 3 to 6 months.
Ray has put together a truly amazing amplifier. It is a thing of beauty, nice and big. I just got back into HF after a number of years. I live in a community in Jupiter, FL that does not allow things like antennas protruding from anywhere on the property. I have two antennas--a tarheel vertical and a carolina windom hung along the perimeter of my home. With Ray's amplifer "helping" me, i am working any DX I can hear even in pile ups. What an amazing piece of hardware! I love it! I had a number of questions early on and Ray was personally there on the telephone to answer the questions. Great customer service. I considered other amps but based on the review I was reading on eham--I decided to go for the "best". As previously reported, the amp arrives in 3 pkgs and in less than an hour (presuming you don't get a hernia lifting it), you should be ready to fire it up. Don't need much power input--used it first with an ICOM MKII with 15-20 watts in, then broke down and purchased a Yeasu FT DX5000---same power in--you can easily push the amp up to eh 2kw+ if you are not careful--will melt the paint off your house! The amp runs very cool. I can't say enough good things about my beast---luvin it! 73's WC3W (when I get my shack organized will have some pix up on qrz)
73, Todd / WA5XX
WA4FOM Rating: 2012-05-23
Anything else is a toy from a cereal box Time Owned: 0 to 3 months.

That's the conclusion I came to when I took the top cover
off to install the tubes and transformers. As the reviews
have intimated, this amplifier has a build quality that I
have yet to see matched. All of the components are very
conservatively rated and, understandably, make this thing
a hulking behemoth that weighs in close to 100 pounds.

When initially assembling the HF-2500DX, it would be best
to do so at the amplifier's final resting place, as moving
it after assembly will likely result in strained human body
parts, even in the best case scenario. The plate transformer
is nearly the size of a basketball, and is HEAVY. Fortunately,
it has a nifty nylon rope handle that makes the entire hefting
procedure more pleasurable than getting your fingers crushed
under the lower edges, never mind looking really stupid, unable
to get your hands out of the chassis. Has that ever happened
to me? Nope, nope nope. That's my story and I'm sticking to it.

Be gentle lining up and inserting those coyote-ugly Russian
military tubes. Before replacing the top cover, take a good
look at the build quality. Ooh. Aah. The band switch is a thing
of wondrous beauty; turning it is a bit of a chore, but you
are rewarded with a reassuring *CLANK* that fills the shack.
It's better than hearing that "frying bacon" sound associated
with cheap switches. I loved the point-to-point wiring between
the circuit boards; pretty much the only internal plug / jack
combinations I recall seeing were for the transformers. No more
flaky connections surfacing 12.835 years from now during that big
Sweepstakes pileup, often accompanied by arcs and sparks and
balls of fire, black and nasty.

I don't think this thing will even work wired into a 120 VAC
outlet. Do yourself a favor and wire up a dedicated 240 VAC
line to this little lady. As with most amplifiers, you'll need
to go to Home Cheapo and get an appropriate plug (I like the
NEMA 6-20P myself) and attach it to the end of the power cord.
Also, be sure to put a decent wattmeter in the line, as the
amp does not have one built in. No biggie.

Tuning the HF-2500DX departs from the traditional tune "for
maximum smoke" or "until you feel your eyeballs start to cook
from the inside out". The goal is to adjust the amp for
proper resonance and a nominal value for grid current, all the
while watching that output power. Make no mistake: if you let
this beast off the chain, it will do over 2000 watts, so do
be careful. Do your bretheren a favor and tune the amplifier
into a dummy load. When I say dummy load, I mean something that
can handle a full 1500 watts. If you're using one of the "paint
cans" be sure to keep an eye on it until you master the tuneup
procedure. Otherwise, you're going to be cleaning up a lot of
boiling transformer oil, or buying a lot of new dummy loads.
If something between the amplifier and the ionosphere (including
the antenna itself) is not properly rated for this level of cold,
unrelenting, merciless, raw, naked POWER, you're going to find
out in short order. Snap. Crackle. Pop. Phew. Stinky.

Bottom line: Read the manual. Heed the warnings. Plan ahead.
You spent good money for a big signal; don't go all cheesy on
the other stuff in the transmit chain.

Though this is a manual tune amplifier, those Viktor Von
Frankenstein (not "FRON-KON-STEEN") man-sized vernier pointer
knobs make returning the amplifier settings to values you have
recorded very easy, often requiring no additional "touch-up"
tuning. Just keep an eye on the grid current on those pretty
oversized meters. If it exceeds safe levels, it will trigger
a general fault, easily cleared by one button. No decoding a
"ZLX29B" microprocessor fault from a display that looks like the
Warp Control Matter-Antimatter Integrator Engineering console
from Star Trek.

All in all, I like having the peace of mind that this kind of
quality gives me. I've owned a number of amplifiers, including the
brand synonymous with the first letter of the Greek alphabet and,
as the headline said, they are toys compared to this one.

Buy it. You'll swear by it, not at it.
K5BJM Rating: 2012-02-13
Godzilla of Amps!!!!!!! Time Owned: 0 to 3 months.
This Amp is built with quality and pride! This Amp is designed with simplicity and strait forward power and dependability in mind. The quality of this Amp is better than ANY Amp made today, in the US or outside the US. I have used and seen many Amps. I have not seen this much quality in Amps costing 3 times as much. If you can find one of these Amps, New or Used, do not pass it up! This Amp lafts at legal limit with 25 to 30 watts drive. 10 watts in gives you 600 to 700 watts out. This is the best Amp made today. You will be able to buy this Amp WHEN I DIE. It will probably bring twice the price I paid for it brand new.
K4YAB Rating: 2012-01-18
Tough Time Owned: 0 to 3 months.
Extremely heavy duty,top quality parts.
The power Transformer is hugh..I,ll never destroy it.
What can I say...Ray a great product,American made and Best price around.
KG4WEL Rating: 2012-01-16
Spot perfect workmanship Time Owned: 0 to 3 months.
This amplifier is the pinnacle of function and workmanship. I have never seen a more perfect production. The amp performs beyond its modest advertised specifications and loafs at legal limit with no more than 30 watts drive.

In my opinion the advantage of this amplifier is its clean signal, the over sized power supply is stiff and a classic full-wave supply, a class act. I previously was using a HK SB-220, which is a nice amp but if I pushed it to 800w or more watts it would began to produce harmonics because of the weak PS flat-topping. I have checked the signal on this amp and it is linear and clean, no more complaints from my neighbors 2kz off at nearly twice the output, so great!

Tips: If you get a HF2500 start slow, READ the tuning instructions carefully and check the chart included with the amp for a general benchmark for tuning on each band. USE THE ALC, this amp has automatic protection but if you over-drive it slightly detuned for a period of time you can feel the heat, USE THE ALC.

This amplifier requires very little drive, I keep my drive limited to about 30 watts.

Thats it, if you have a opportunity to get this QRO amp do it, you will be very happy!

73, Scott KG4WEL

N5TF Rating: 2011-12-26
Outstanding AMP! Time Owned: 6 to 12 months.
If you ever want a amp which provides brute force with minimum drive, easy to operate, easy to work on in the rare occasion that you need to, this is the amp...The tubes are cheap compared to others in this power range and readily available. I have owned many amps and this is by far the best amp I have ever owned. Bought mine second hand and it is a real pleasure to have this much head room in an amp. Get one, buy yourself a spare tube for around $100 bucks and you will be set for a very long time. The 4CX800A tubes also known as GU74B are tough and very forgiving..and did I mention cheap, you can buy them used on EBAY for around $100 including shipping from Russia. Ray provides great customer service if needed..This is a great American Made Product..Buy one today, you won't be sorry!
WQ4E Rating: 2011-11-08
great amp and service Time Owned: more than 12 months.
i have had the 2500dx amps over 10 years now.i have 2 and i love them.i have never had any problems and ray is always ready to help.one of the best and easy to talk to.a 5 plus.bob/wq4e
NY4DX Rating: 2011-10-27
Still the Best Time Owned: more than 12 months.
I've owned this amp for a few years now and can report only one equipment problem.

The timing IC for the warm up in rush circuit went bad. Talk to Ray and he had a new one to me in two days at no cost. Replacement was simple.

Other than that the amp has worked perfectly..max legal limit on all bands with minimal drive power...clean and solid output.

The only improvements that could be made:

1. The 2 minute warm up time is a pain especially chasing DX. I am planning to purchase the QRO HF-2000 in addition to this unit so I will not have a warm up time concern in the future...I will keep this brute ready for the Dxpeditions pile up busting.

2. The fan is very noisy...I wish there was another type muffin fan that could work and move the air volume needed. If you dont use headphones it may be annoying to some...consider using a pair of Bose noise Cancelling headphones during prolong operation.

If you use headphones to solve this problem, then you have to deal with the numbskulls that can't tune their equipment...antennas or amps except on top of the DXpedition frequency.

Please you do not have to hit the tune button on your radios if you can't hear the station...go off frequency and do this ....then come back on top of the DX station and ask "Who is the DX? then ask..."What frequency are they listening? Why all of us who have been listening to them for hours...trying to work them on a 20-50 khz spread split will gladly respond to your requests for the DX information...that you would have if you only listened instead of jumping on top of the frequency. (lol)

Nice thing about this amp if you preset the amp for each band you can get away without tuning this beast within the entire sub band (ssb or cw) portions. The amp works plain and simple.

Have a good quality watt meter to make sure you dont exceed the legal limit. If you use a tuner, make sure it could handle extra overdrive of the input power...you may arc your tuners or fry your baluns if you are not careful.

This is a solid piece of equipment not anything made by MFJ.

Other than that...you would have to pry this amp from my cold dead fingers before I part with it!