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Alpha 9500 vs. Acom 2000A

Discussion in 'General Technical Questions and Answers' started by KD1MA, Mar 4, 2010.

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  1. KD1MA

    KD1MA Ham Member QRZ Page

    These two amps seem to be of comparable quality. The price on the Alpha is about 40% more than the Acom. I am told that service for the Acom amps is done in MA which for me is only a 70 mile drive versus an expensive shipment to CO although I have no input on turn around time for either amp. The Acom also has a 4 year guarantee. I am not sure about the Alpha guarantee as my computer does not want me to connect to the RFConcepts site for some reason.

    Has anyone had experience with both amps and can give me a solid comparison report keeping the price differential in mind?


    Bob KD1MA
  2. K6AER

    K6AER Ham Member QRZ Page

    Buy American

    The ACOM 2000 is basically an upgraded copy of the Alpha 87A but with tetrodes. Alpha had ACOM building their manual tune amplifier in 1991 using a pair of 4CX800A7’s. Then ACOM looked at building the Alpha 87A. Build quality suffered with the 91B and Alpha brought the production back to the US. Because of the Alpha 87A product, ACOM was able to design their current 2000A which copied the basic design of the 87A. You will note the similarities in layout.

    Alpha has stopped using the 4CX800A7 tubes in their manual tune amplifiers with the Alpha 8100. This was due to tube scarcity. In 2009 Alpha started to producing the 8410 manual tune amplifier which uses a pair of massive 4CX1000A’s. ACOM, which still uses the 4CX800A7, has put on a good face saying there is no problems getting the tubes but that just is not the case. TenTec, Alpha and other have stopped using the tube along with most other manufactures. I have no idea where Brian at QRO is getting tubes. All the tubes that are available are NOS (New Old Stock) from the 1990’s and are floating around in various locations in Russia someplace.

    The Alpha 9500 uses the 3CX1500B/8877 triode and is very linear. These tubes are made by no less than 5 manufactures and will be around long after amateur radio has left the planet. No problem with tube availability.

    I have watched the Alpha 9500 amplifier putting out 3000 watts plus sending CQ Dayton into a dummy load at the ham convention for three days straight. The amplifier design, quality control and component selection is very high with no compromises. In addition Alpha still supports older designs going back to 1977. When running the amplifier at 1500 watts you have a lot of head room. The amplifier uses a 3.5 KVA transformer with a full wave bridge.

    On item always to consider is where the factory service is located. Alpha is in the US. ACOM has a service location in Massachusetts, but the manufacturing is in Bulgaria.

    It should be noted that only the Alpha 9500 is type accepted (Parts 97.317) by the FCC for 12 and 10 meter operation. None of the other amplifier manufactures have FCC type acceptance for operation above 21.450 MHz. What has been done is the past is to make modifications available for the ham to do and place ten meter operation into the design and that is fine if you feel competent modifying you new amplifier. That is no longer allowed by the FCC. 1500 watt amplifiers must now have a gain of less than 15dB at legal output and they must have zero gain from 26-28 MHz.

    Both amplifiers have a 4 year warranty. The Alpha uses the original factory tube warranty which is 1 year. I don’t know what the tube warranty is for the ACOM tubes.

    When receiving an amplifier quote also get a quote for spare matched tubes (same manafacturing date) ask what the amplifier manufacture will sell you a spare set of tubes for. I would make that a condition of the sale.

    With a single tube that problem goes away.
  3. WB2WIK

    WB2WIK Premium Subscriber QRZ Page

    Great writeup, Mike.

    I think THL has a high-powered solid state amp that is certified for operation on 12 & 10 meters also (I believe it uses a frequency counter to shut it down between 26 and 27.9999 MHz, and internal attenuation to limit the gain).

    But it's an interesting point if the 9500 is the only high powered tube amp on the planet to be so certified; I didn't know that!


    Steve WB2WIK/6
  4. K7FE

    K7FE QRZ Lifetime Member #1 Life Member Platinum Subscriber QRZ Page

  5. KD1MA

    KD1MA Ham Member QRZ Page

    My Trend Micro Security Software, for whatever reason, has that site blocked as one that has passed on viruses in the past. I was able to overide the block and get in.

    The price is actually less for the 9500 than I had thought. I was under the impression that it was closer to $9,500. It is listed as being much closer to the Acom price. Additionally, the 9500 uses the same tube as my AL1500 although Alpha uses the Chinese version and not the original Eimac super tube and then calls it an "inexpensive" tube. lol However my AL1500 has been running with no more problems than 2 blown fuses and the same tube for the past 16 years!

    I guess I will add the Alpha 9500 to my wish list.
  6. WB2WIK

    WB2WIK Premium Subscriber QRZ Page

    I'd go with the "Buy American" theme if possible. Alpha's been around a very long time and has been very loyal to the amateur community. They allow generous trade-ins (on older model Alpha amplifiers), and seemingly can service and support anything they ever built -- remarkable. The only other company I can think of (who's been in business more than twenty years) in that category is Ten Tec.
  7. W9GB

    W9GB Ham Member QRZ Page

    Steve Farkas, WA2NFR president of Alpha/RF Concepts posted a letter in late 2009 about price reductions on Alpha products.

    The list price for the Alpha 9500 is $7,950 plus shipping and handling

    The availability and cost of replacement tubes should be one criteria on your list.
    HOWEVER -- If properly operated and cared for the ceramic RF tubes should last your lifetime!

    Alpha has their pricing for the tubes used in their amplfiiers.

    4CX800/GU74b Russian (Alpha tested) used in Alpha 91b, 99 and 8100 - $ 350
    3CX800A7/YC-238 Eimac - used in Alpha 86, 87A, 89 - $ 875
    3CX1500A7 / 8877 Eimac - used in Alpha 77, 77D, 77Dx, 77Sx, 9500 - $ 1,395
    3CX400A7/8874 - used in Alpha 374, 374A, 76, and 78 - $ 450

  8. K6AER

    K6AER Ham Member QRZ Page

    You are right again.


    You are correct. The THP series amplifiers have a microprocessotr that reads the frequency to prevent 11 meter operation.

    The new requlations under part 97.317 requires no gain from 26-28 MHz. This will be problematic for older designs. In the past manafacures have left out the ten meter connection and required the licensed owner to complete the ten meter input curcuit or add the completion of the ten meter low pass filter. The new ALS1300 does that. Under the new rules that is no longer permissable. All that is required for the new ALS-1300 to pass ten - twelve meters is a jumper on the low pass filter board. I did not include solid state amplifiers in my reply for the origional post did not go there.

    Let's have lunch in Denver next week.
  9. WB2WIK

    WB2WIK Premium Subscriber QRZ Page

    It was great to meet you for lunch a few weeks ago, Mike!

    I don't know about "next week," but I'm sure I'll be in Denver sometime later this year and I have your phone number stored in my cell phone now, so I know how to reach you if I don't catch you on the air.


    Steve WB2WIK/6
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