> I have never heard anyone say that the AL82 was prone to
> failure, or that the components were delicate or hard to
> find. In my opinion an amp like this, bult like a battleship,
> if run even a little conservatively, will serve one for many
> more years, without failure than amps like the SB220, TL922,
> or the others, all of which are underdesigned with components
> stressed close to their limits.
There is a HUGE difference between the design of the AL-82 and
the SB-220, TL-922, L-4B, etc. The AL-82 was designed in a
regulatory environment with 1500 W PEP output (about 2300 W DC
input) while the SB-220, TL-922, L-4B, etc. were designed in
an era where the legal limit was 1000 W DC input. The older
amps weren't "under designed" - they were designed for the
rules in effect at the time with a reasonable safety factor as
shown by the amount of "abuse" they regularly survive.
The difference represents 50% more plate dissipation (heat),
significantly more stress on the band switch and plate choke,
greater energy stored in the filter capacitors, and higher
fault currents.
Any user who regularly pushes the older amplifiers to 1500 W
is courting catastrophic failure. Will some amps let the
user get away with abuse - yes. I'd stack the L4B up against
any of the "modern" amps (particularly with some modern fixes
like a faster T/R relay and low voltage PTT line) but 1500 W
is still pushing the limits for devices designed for operation
at 1000 W DC.
73,
... Joe, W4TV
> -----Original Message-----
> From: amps-bounces@contesting.com
> [mailto:amps-bounces@contesting.com] On Behalf Of Bill K2OWR
> Sent: Friday, January 29, 2010 2:19 PM
> To: Lee Buller
> Cc: amps@contesting.com
> Subject: Re: [Amps] Good amp to buy
>
>
> :::: Thanks for understanding Lee.
>
> I have never heard anyone say that the AL82 was prone to
> failure, or that
> the components were delicate or hard to find. In my opinion
> an amp like
> this, bult like a battleship, if run even a little
> conservatively, will
> serve one for many more years, without failure than amps like
> the SB220,
> TL922, or the others, all of which are underdesigned with components
> stressed close to their limits.
>
> BTW, none of those are made any longer, nor have they been
> for many years.
> My AL82 is 20 years old now and I expect will likely outlive me.
>
> Oh, and if you're a contester and can't fix your own amp,
> stick to the 811,
> or 572B type amps....all solid designs!
>
> BILL K2OWR.....I'm gonna pay for my words, I know:-(
>
>
>
> > Bill
> >
> > I too like the AL-82 and have not trouble with mine. But,
> I run mine
> > in
> > conservative mode and not full throttle. Nice amp, but
> like all amps they
> > need to be tuned properly. The QRO-2000 is a nice amp too,
> but I don't
> > think he makes many of them anymore.
> >
> > I do like the 3-500Z bottles for cost.
> >
> > Lee - K0WA
> >
> > In our day and age it seems that Common Sense is in short
> supply. If
> > you
> > don't have any Common Sense - get some Common Sense and use
> it. If you
> > can't find any Common Sense, ask for help from somebody who
> has some
> > Common Sense. Is Common Sense divine?
> >
> > Common Sense is the image of the Creator expressing
> revealed truth in
> > my
> > mind. - J. Wolf
> >
> >
> >
> >
> >> "... I'd like to weigh in on this.....
> > The Ameritron AL82 seems to me to be the most rugged and powerful
> > amplifier
> > in the twin 3-500Z class.
> > The power supply alone makes all the others seem puny and
> the output is
> > higher than all others in this class.
> > They can be had for as little as $1200 used and are truly a
> contesters
> > dream
> > amplifier.
> > _______________________________________________
> > Amps mailing list
> > Amps@contesting.com
> > http://lists.contesting.com/mailman/listinfo/amps
>
> _______________________________________________
> Amps mailing list
> Amps@contesting.com http://lists.contesting.com/mailman/listinfo/amps
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|