[Amps] Alpha 87A Problem

Bob Wilson, N6TV n6tv at arrl.net
Mon May 27 21:30:25 EDT 2019


Did you try disabling AlphaMax by manually tuning the amp with the buttons
and saving the solution for each band segment?

Maybe the frequency counter was damaged, perhaps by nearby lightening?

Or is the AlphaRemote software trying to tell the amp what to do?

73,
Bob, N6TV

On Mon, May 27, 2019, 6:10 PM Michael Tope <W4EF at dellroy.com> wrote:

> My Alpha 87A had been working  pretty faithfully up until the end of
> March / early April. I haven't used it since then until this weekend.
> Normally I operate remotely, but this weekend I had to come up to my
> remote site for something else, so I decided to play a little bit in the
> CQ WPX CW contest. I noticed right away that the tuning on the 87A
> seemed squirrely on 40 meters (the amp kept re-tuning even thought I
> wasn't changing frequency and VSWR appeared stable). When I moved higher
> in the band to call CQ it seemed to settle down and was delivering a
> steady 1300 watts.
>
> This morning I tried operating 20 meters. At first when I was calling
> people low in the band, the amp seemed okay, but when I went higher in
> the band, it started acting up where it kept hunting for a new tuning
> solution and in some cases it would fault. After a little fiddling, I
> noticed that the frequency readout on the Alpha Remote software was
> jumping all over the place (in some cases up to 16.3 MHz!!). In one
> case, because of the faulty tuning, I noticed that the grid current
> reading was really high, but the grid trip circuit didn't protect the amp.
>
> Any ideas where to start? Seems like it might be a microprocessor
> problem. When it is stable, the amp is making plenty of power (1300 to
> 1500 watts).
>
> Reducing drive, doesn't seem to help, so I don't think it is an RF in
> the shack problem. I would put it on a dummy load, but my Cantenna is 60
> miles away at my home QTH (next trip up I will bring it).
>
> 73, Mike W4EF...................
> _______________________________________________
> Amps mailing list
> Amps at contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>


More information about the Amps mailing list