Hi Rob: The point of my post was not to dispute your points. Sorry if that
seemed to be the case.
If the goal is to put 1.5 KW key down for 30 minutes into a dummy load to prove
how robust one's amplifier is, the performance of the AL-82 might prove
problematic. Might. For someone who wants legal limit output, under the
conditions I, and many others, operate under, the AL-82 has done everything
needed, and has been reliable doing it. If I ever melt the bandswitch, blow up
the transformer, or melt the tubes, I might revisit my strategy.
I chase every DXpedition that comes on, on every band and every mode we hear
them on. After years of having no time to chase DX, now I chase Challenge
credits making up for lost time. Sometimes I change bands 10 to 20 times a
day. Day in and day out, the AL-82 makes legal limit power, without a problem.
I could spend 2 to 4 times the money and get an amp that would do 30 minutes
at 1.5 KW key down without any worry. Heck, my Alpha 77DX will do that. I
hardly ever use it, only acquiring it to help a friend out and because it was
like new. No, it is not for sale, before anyone asks :-)
I guess this is like cars. It is a matter of personal preference and
philosophy. I had an MB S-500, purchased while we were working. My wife
totaled it recently. I replaced it with a Toyota Camry. You know, the Camry
is just as utilitarian as the MB.
In summary, it is not necessary to spend more than a used AL-82 costs if all
you want to do is make legal limit power to chase DX on the band. If someone
has the resources and wants to go more heavy duty, that is their perogative.
Not wishing to beat a dead horse, I will QRT and go back into my usual lurking
mode now.
73 Charlie N8RR
> Date: Mon, 6 Feb 2012 18:45:10 -0600
> From: ranchorobbo@gmail.com
> To: amps@contesting.com
> Subject: Re: [Amps] Different amp recommendations
>
> Not looking for an argument, but nothing you have written has
> unsubstantiated what I posted. As I wrote earlier, the factor is
> transmit time. someone wrote that Ameritron says 1.5 KW with that amp
> for 30 minutes. I guess the blower on high speed is not one of those
> quiet jobs.
>
> I would be delighted to be proven wrong. Run an AL-82 into a DL @ 1.5
> KW dead key for 30 minutes. do it on 1.8 MHz. Let us know how it
> does. You have to have an exciter that can do the drive power for
> that time too. Maybe one of the 200 W SSB rigs, but I'd put extra
> fans on the heat sink. Rig with pair 6146 or 4D32 will work okay for
> the driver. Don't use one of those Cantenna DLs--you'll need a 1 KW
> or more Bird or a few 200 W. Carborundum resistors paralleled with a
> fan on them.
>
> 73
>
> Rob
> K5UJ
>
>
>
> On Mon, Feb 6, 2012 at 3:35 PM, Charlie Young <weeksmgr@hotmail.com> wrote:
> > I have two AL-82 amplifiers, plus an Alpha 77DX, an AL-1500 and an
> > assortment of other amplifiers. The one I use 90% of the time is the
> > AL-82, precisely because it takes a licking and keeps on ticking. It is
> > the Ford or Chevy pickup truck of legal limit amplifiers.
> >
> > I can change bands with it in 10 or 15 seconds, and don't have to baby it
> > during tuneup. It has no trouble producing legal limit output on any
> > band. One of the AL-82 amplifiers is on standby when I am in the shack,
> > which being retired is nearly all the time. I run 1500 watts output with it
> > on RTTY. I am not a contester any longer but am a serious DX'er. My RTTY
> > transmissions are short DX pileup calls, not 10 minute ragchews, which may
> > be why the equipment has not failed. Maybe if I were a RTTY contester or
> > ragchewer, the results would be different.
> >
> > Certainly these AL series amps are not built like Alpha amps but they make
> > RF power at the legal limit for far less cost. I push the heck out of this
> > one and don't worry about it. If we do ever lose a tube (it has not
> > happened yet), it won't break the bank. These Chinese graphite tubes seem
> > to be pretty rugged. I can fix anything that would go wrong and can get
> > the parts from Ameritron.
> >
> > At $1500 to $1800 on the used market for an AL-82, it is a pretty cost
> > effective way to make legal limit power, in my experience.
> >
> > Why do I have two? They came together in an estate sale. One of my friends
> > is using my spare AL-82 while the pin diodes are replaced in his Alpha 87.
> >
> > Others may have different experiences. Your mileage may vary.
> >
> > 73 Charlie N8RR
> >
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