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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
AC4VM Rating: 2020-07-08
One of the Greatest Amps Ever Made! Time Owned: more than 12 months.
I have own my QRO HF-2500DX since new and have never had any problems with the amp. I have run 1.5 KW on all modes and it's always performed outstanding. Don't listen to the two reviews below mine because they must have bought used amps that had been abused. I can take any amplifier and run it beyond it's limits all the time and make it break. As far as ever repairing the amp if ever needed, they are several company that can do that. The amp has great schematics and very easy to follow if you know electrical theory, electronics and how to read a schematic. All the parts are available on the open market if you know where to look. Besides the cabinet and chassi Ray did not use preparatory parts. The bottom line is if you can find a QRO HF-2500DX that is a one owner and not been used by some abusive CB'er, humm, I mean Ham buy it. It's a TANK.
W5RG Rating: 2019-12-30
DON'T WASTE YOUR MONEY Time Owned: more than 12 months.
I have had the two model and the three model. the design of these amp are trouble and very had to follow schematics and were not up to date and forget finding anyone to work on them.. Yes he used very heavy duty parts and transformers and if your lucky it will last but if it breaks you are SOL! I had two and sold them both. I lost my rear on selling one..never again..Ameritron are better choices...
KA4KOE Rating: 2019-12-30
Do not recommend Time Owned: 6 to 12 months.
I traded this amp for something else at a loss. The design for screen voltage regulation is very poor with Vsg ~150V higher than the tubes' spec's. Ran hot. Design of the board layouts makes servicing difficult. If you buy NOS tubes be sure you getter them for 24 hours first; no Vsg, no Vp, no Vg....just heaters on, or you risk arcing of the finals. Outlets such as DX Engineering do NOT getter these tubes prior to sale. There are better solutions for legal limit power than this amp. Plus, the owner is in retirement so forget about service or even email advice.
W8QW Rating: 2019-12-29
Great Amplifier Time Owned: more than 12 months.
I bought this amp about 18 months ago from a guy who had tried to use it on 11 meters. The bandswitch, tube sockets and 2 of the PCB were trashed. Ray took the amp in, fixed it and upgraded it, all for a nominal price. It operates smooth and really provides a punch when pile-ups are overwhelming. I've owned quite a few amplifiers and this amp is by far the best. An excellent amp, and if you're a serious operator, well worth the dollars to own one. I only wish Ray were still in town and available. Rather, he's in Florida selling commercial real estate. Go figure.
KM1H Rating: 2019-11-05
Run at 1500W and be satisfied Time Owned: more than 12 months.
A fine amp at 1500W, just dont expect long tube life if pushed to its max capability as those 600W PD Russian surplus tubes are not designed for that, the 4CX800A designation is a fraud by the then US distributor.

The 30-40 year old replacements are drying up as well as developing internal gas and new Svetlana production are around $750 each.
W4BSS Rating: 2019-11-04
Beast of a Amp Time Owned: more than 12 months.
I've had my QRO for many years and I must say everything about this amp is heavy duty. Mine has the 3 Peter Dahl transformers. The Plate Transformer is massive resulting in a very deep well to drink from.

The following power measurements are taking from my calibrated commercial Agilent power meter into a 5 Kilowatt 50 ohm load: 14w in = 1500w+ out... 20w in = 2000+ out... 30w in = Coax smoking power. All jokes aside this is a great amp and the tubes can be replaced for a few $$$.
W9BHI Rating: 2018-02-17
Great build quality, very poorly designed Time Owned: more than 12 months.
I bought this amp used and it works ok but after snooping around inside, I found the screen voltage to be 140 volts higher than the tube max.
spec.(350)
The screen current meter has the wrong shunts for the scale.
The screen meter is off by 50ma. full scale and 25ma. at half scale.
The max screen current cutoff should be 80ma. max.
(two tubes)
I measured the trip current to be 115ma.
The tubes would be toast by the time the overcurrent would trip.
If you have to change tubes, you are on your own trying to figure out what the correct voltage of zener diode to use in the bias circuit to set the resting plate current.
Good luck on trying to contact QRO for a repair on this amp.
There are better amps out there for less money.
WT4P Rating: 2016-12-07
Power and reliability Time Owned: more than 12 months.
I aquired a pristine QRO DX2500HF two years ago. What a great amp. I use it almost everyday. 30w in gives 1500w+. This may be the last amplifier I buy.
NA1A Rating: 2015-06-19
Unbelievable! Time Owned: 0 to 3 months.
All I can say about this amp is OMG. For a legal limit plus desk top, this got to be on the very top of the list (and I've had plenty of different amps, you name it, I got it).
20W in 2500W out, grid barely wiggle, plenty of headroom. Clean as a whistle SSB modulation, extremely quiet and stable of an amp.
No software to fail, no EBS complexity, no gimmics nor trick. Just a plain old straight forward design, heavy duty commercial quality components, brutal power!
My Alphas now are up for grabs. Any takers?
W5VYY Rating: 2013-11-13
Failure after only 10 years Time Owned: more than 12 months.
I purchased my QRO HF-2500DX in April of 2003. I have used it twice a day on 1990 kHz for over 10 years. Then SURPRISE the screen grid circuit failed. Since I am now old and slow I decided to send it back to QRO.

I called Ray and of course he was so nice. Told me NOT to use Styrofoam peanuts to pack it as he hates the mess he has to clean up. Ray repaired the unit and replaced the meter lights that had not worked for years.

He even cleaned up the 10 years worth of dirt inside the amp. I had it back and on the air in about a week.

Now for the bad news.

1. When it came back it was tuned up on 20-Meters. I did not realize it would work UHF. First time the band switch had been off top band.

2. While it was gone I had to use my 800-watt Heathkit SB-1000 amplifier which is QRP on 1990. My top band buddies told me "Nice driver"

Read the quotes from the 1990 geniuses I talk to everyday on my QRZ.com web page. No mater how smart you are, you will be smarter.

Thanks Ray for the great service you provide. I hope I am good for another 10 years.

John W5VYY


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Earlier 5-star review posted by W5VYY on 2003-07-03

You will need help installing the 45 pound Peter Dahl power transformer and 17 pound filament/control transformer in this bad boy. You will then need help setting it up on your heavy duty desk. The amp is much larger than it appears in the photo's, you need a lot of desk space. Turn down the power on your exciter! 35 watts is all you need for 1500 watts out.
1. Excellent quality and workmanship.
2. Big dog band switch. No arcing no sparking.
3. Easy to tune using the screen grid current meter. No more tuning for maximum smoke.
4. Comes with extra case screws and fuses. Nice touch.
5. 4CX800's cost less than 3-500's.
6. Quiet blower fan.

The only negative thing I can think of is the two minute warm up time. Buy one and you'll love it.