GOOD CW low powered amp suggestions to replace 811H

Discussion in 'Amateur Radio Amplifiers' started by W9RAC, Nov 17, 2019.

ad: L-HROutlet
ad: l-rl
ad: Left-2
ad: abrind-2
ad: Left-3
ad: L-MFJ
ad: Subscribe
  1. KH6AQ

    KH6AQ Ham Member QRZ Page

    By the way, I run my AL-811 (572B tubes) at 600 watts on off keyed CW and 500 watts in digital modes. You could do this with three 572B tubes, and as G3YRO says, two 572B tubes will be fine at your 350 watt level.
    W9RAC likes this.
  2. W9RAC

    W9RAC Platinum Subscriber Platinum Subscriber QRZ Page

    Dave I think a great deal of the problem is the quality of the tubes. That amp has never had more that 28 watts or so run to it ever. Generally I run more 25ish or so. This is the 4th 811H I have owned. Never had a problem with one before but I never used one as a dedicated CW amp. I was told by Rob at the Ameritron factory the tube had a hole in it. He also said its not overly unusual to have a bad Chinese 811a tube right out of the box, and they are not good tubes. I had considered using a better quality tube which is where I am sure is the origin of the problem. After some deliberation I have moved on to a solid state amp, Acom 1200s. I did have the 811H checked out and retubed. Ill be selling it. Thanks for your comments sir. 73 Rich
  3. KD2ACO

    KD2ACO Platinum Subscriber Platinum Subscriber Life Member QRZ Page

    I think you're going to really like that Acom! Tell us how it works out (for those of us who like to live vicariously through other's equipment acquisitions). :)
    W9RAC likes this.
  4. W9RAC

    W9RAC Platinum Subscriber Platinum Subscriber QRZ Page

    I have a Acom A2100 and have used it 50% of the time SSB shared with a Alpha 8410. I have owned the Acom for a couple of years now. Great Amp. The company seems to make a great product. What sold me with Acom is DX Engineering is a service center for repair also and the experience I have had with the Acom I own now. Having never owned a solid state amp to date I hope the experience will be the same as moving into solid state rigs and computer hard drives. Both have been great. I'll post a few lines when I get and use it, Wednesday. 73 Rich
    KD2ACO likes this.
  5. K6BSU

    K6BSU Ham Member QRZ Page

    Manufacturers like to hide tubes way in the back, or generally cover them up. So how do you know if tube plates show any color when transmitting?

    I like to watch tubes, so I put them out front.

    Attached Files:

  6. W9RAC

    W9RAC Platinum Subscriber Platinum Subscriber QRZ Page

    Uhhhhhh my first impression of the Acom 1200s, its a 10! I feel like I have been transported into the 21st century. I have had time to make some CW contacts so far and it may be the death of all my tube amps if what I see now continues! 8 watts in, 320 out. Just right, 73 Rich
    Last edited: Nov 26, 2019
    KD2ACO likes this.
  7. KM3F

    KM3F Ham Member QRZ Page

    For a solid reliable amplifier at 400 watts, consider an AL 80B optioned for 400 watts on the power supply.
    It has that option supplied in the design.
    It hardly runs the 3-500 at it's plate rating.

Share This Page