Acom or Ameritron...??

Discussion in 'Amateur Radio Amplifiers' started by W3AMM, Jan 3, 2017.

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  1. K0OKS

    K0OKS Premium Subscriber QRZ Page

    The other advantage to used gear is that there is no warranty to worry about voiding! If something breaks you can fix it right away (assuming it's not a blown transformer or something else requiring parts). Of course that can also be a detriment...

    A new piece of gear that fails is the worst because you have to send it off to be fixed (for shipping $$) and wait forever.

    I do wonder how repairable the Elecrafts are. I am the kind of guy that likes to take things apart and fix them when they break. I try to eschew gear with tiny surface mount components, and custom ICs or custom code in a microcontroler vs. easy to source analog ICs and passives. I went that route with my 7300. It works great, but I always felt the spirit of Amatuer Radio was hacking and repairing things, or even better, home brewing stuff. I just got into the hobby, but I grew up with the handbook as my electronics guide.
     
  2. KD2ACO

    KD2ACO Platinum Subscriber Platinum Subscriber Life Member QRZ Page

    Joe, you and I think alike! :D
     
  3. N7ZDR

    N7ZDR Ham Member QRZ Page

    I would recommend to stay away from the 811 or H models as there will be nothing but troubles and you will regret it. I had (sold it) a Acom 1000 and was very happy with it. It will run 1 kw easy and the tuning is about the fastest on the market for manual tune amps.
    Just think of a Acom 1000 as a Alpha version of the AL-80B. I was sold on the quality of the Acom brand so I bought a Acom 1500, this is now my 1st go to amp. Again-- the quality is 1st class and tuning is quick and easy (any band =10 seconds).

    I also have the OM2500-- I haven't had this very long so cant comment much, but I will say that the quality is every bit as good as either the Alpha or Acom. However the ease of tuning is not quite as easy as the Acom.

    If you limit your self to 500 watts output-- as time goes by you will long for more power!

    Cheers,
    Larry
     
  4. K3RU

    K3RU Ham Member QRZ Page

    My AL1500 is currently on my test bench waiting to be worked on. I'm having motivational issues with digging into it. I still like the amp and when I repair it I will most definitely put it back in service, but will have to decide where to put it as the space where it was sitting on my operating table is now occupied by a new ICOM IC-7600 purchased for well under $2600 thanks to ICOM's "instant rebate" program. For years I was fixated on someday owning a IC-7700 but have grown out of it for many reasons, mainly the cost. The IC-7600 which probably will be discontinued to make room for the upcoming IC-7610 is in my opinion too good to pass by, as I am not interested in the touch-screen on the IC-7610, even though the IC-7610 will probably be an excellent radio. I am very impressed with the IC-7600 so far and am quite happy with it, despite the Sherwood ranking which many see as a shortcoming.

    The AL-80B I purchased really as a "fill-in" for my ailing AL-1500 is a nice amplifier I must say. Now that the AL-80B is working properly - I'm keeping my fingers crossed - I actually prefer it to the AL-1500. The bandswitch is much easier to turn, and the overall look and feel seems "right". At a "mere" 44 pounds the AL-80B is much easier to move around compared to the some 77 pound AL-1500. What really sold me on the AL-80B was the 3-500ZG tube. I work 99% CW and like the 800watts the AL-80B makes. At around $200 a pop currently, a 3-500ZG is "affordable" to replace. I just hope my amp's 3-500ZG never arc's as they sometimes do.

    My biggest gripe - and fear - of these amps, especially the AL-1500 is that in my opinion they are not that easy to troubleshoot, especially if you suspect a defective tube. The warranty on my 8877 expired over 7 years ago. I don't have a known good spare $1500 8877 sitting around to just "drop-in" as a troubleshooting step. After eliminating the obvious, you are left wondering about the tube. Not willing to drop $1500 for a "genuine EIMAC 8877", or try to find a "good" used tube, I parted with some $800 for a new CHINESE "Taylor" 8877. The warranty clock is ticking on the CHINESE 8877, so will have to get it into my AL-1500 soon. If I "throw enough parts" at the AL-1500, maybe I can fix it!

    If I decide to let the AL-1500 go, which is a distinct possibility, there will be either a new ACOM or ELECRAFT solid state amp in my future.
     
    Last edited: Jan 4, 2017
  5. G3YRO

    G3YRO Ham Member QRZ Page

    One of the reasons so many people go for a Valve amplifier is the fact that it will match a range of impedances, so if you have an antenna that is more or less resonant, you won't need a high power ATU (as you would probably need for a transistor amp)

    I would also recommend buying a Used amp, rather than brand new. The money you would save means that even if you had to replace Valves, you will still be better off! (but best to go and see any equipment working, to see how it performs)

    My attitude with radio equipment has always been the same as Cars . . . given that I have a certain limited amount of money to spend, I'd rather have a really good Used model, than an average New one !

    This is especially true with Valve Amplifiers, as technology hasn't really changed at all. If anything, the older Amps are usually better engineered than the newer ones!

    I've just bought a Kenwood TL-922 . . . and really pleased with it.

    Roger G3YRO
     
  6. W1QJ

    W1QJ Ham Member QRZ Page

    I would like to hear specific beefs ( problems) you have had with your AL-1500 if you don't mind.
     
  7. W1QJ

    W1QJ Ham Member QRZ Page

    Just read this, I guess that makes my question moot. If you want to unload the 1500 " as is" let me know. I find them extremely easy to fix, that's why I own them. I'll even buy it without a tube, you can sell a good tube separate for more money.
     
  8. W3AMM

    W3AMM Ham Member QRZ Page

    Thanks for the suggestion, i looked at it online and that amp just may be the ticket since it is some what set up for my kenwood it may be a good choice. Thank you so much....
    When i make a decision about my final out come i will post the results.
    Thanks to all that have replied...i had a good feeling i would get some honest opinions about what im looking for the kpa500 seams quite nice
    73s Doug.KC3GJY
     
  9. K3RU

    K3RU Ham Member QRZ Page

    W1QJ: You and I had a series of email exchanges discussing my AL1500. I got an OO report informing me of 60hz HUM on my signal. I verified that as being true and replaced the .01 filament choke caps, did filament xmfr tests as per your suggestions, and lots of other things with the amp on my operating table. Went as far as I could with it without a spare tube to install. Now it's down on the test bench probably "laughing" at me. I do have a spare tube now on hand and hope to get into the amp soon.

    There is some 2VAC 60hz stray voltage sitting on the AL1500 coax input jack. When driven by a TS940S the drive rf is modulated by this 60hz and the amplified output signal does indeed have 60hz modulation, looking like about a 50% modulated AM signal. This occurs with two separate TS940S exciters. The two exciters RF output are perfectly clean when fed through the amp, but get the 60hz superimposed on them when driving the amp. Considering how simple the AL1500 input circuit is, I'm suspecting the 8877 tube. You suggested the filament xmfr had leakage. I unbolted and insulated it and retested as per your instructions, with no change in the amp output signal. Had a conversation with a DX Engineering tech and was told they had an AL1500 in for repair with such a problem, and ended up sending it off to Ameritron for repair. The tech thought the problem was in the input matching circuit, which is buried behind the front panel. We shall see.

    You didn't believe there was 60hz hum on the amps output and wanted to hear it for yourself. We were supposed to meet on 40m CW some evening but that never happened. Remember?
     
    Last edited: Jan 4, 2017
  10. WB5THT

    WB5THT Premium Subscriber QRZ Page

    I have an Acom 1000 and I'm 100% pleased with it; I wanted a tube amp to help mitigate my stupidity. It's happy with any SWR under 3:1.
     
    AC9VT likes this.

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