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Re: [Amps] Amplifier Lifetime

To: Mike Dishop <n8wff@yahoo.com>, amps@contesting.com
Subject: Re: [Amps] Amplifier Lifetime
From: MU 4CX250B <4cx250b@miamioh.edu>
Date: Sat, 7 Oct 2017 13:03:54 -0600
List-post: <mailto:amps@contesting.com>
Good comments, Mike. Re early 9500 issues, i’d add blower problems to the
list. The original blowers had sleeve bearing motors, with the bearings
poorly supported by the mounting flange. The newer blowers seem fine, and
the retrofit repairs to the original blowers (Changing the mounting bracket
and swapping ball bearings for sleeve bearings) also worked well. I know
that some other small components were changed, as well, but your point
about reliability and quality construction is well-made. The 9500 is a
lovely amplifier.
73,
Jim w8zr
Sent from my iPhone

On Oct 7, 2017, at 9:59 AM, Mike Dishop via Amps <amps@contesting.com>
wrote:

Manfred has proven what a rotten businessman I am. I have to admit I'm
beaten.  He stated that companies design the product to fail soon after you
buy it and to be obsolete.

I, on the other hand, design every piece of communications equipment to
last as long as possible, and to be as robust as possible, and use it as if
my life depended on it.  When you are offshore, taking on water, and
listing to one side is NO TIME to have to reboot your radio or fix it!


Secondly, I design every circuit with the questions of how can it fail, and
what happens when it does?  I then extend that question to be How can I
make this failure fail safe so that things are not destroyed or anyone
injured?  An example of the solution might be two sets of resistors in
series paralleled with another set in series, so that if one resistor fails
open or closed there is still a path to complete the circuit, and because
of latitudes with designs and wattage ratings, maybe even to function
properly.  Of course this takes up more real estate, costs more money and
is more complicated to assemble.

Given the comments here about the 87A and the number of people still using
them I have to say that Alpha must have done a pretty good job.  Carrying
on the brand's tradition for quality and longevity is something I intend to
uphold.  Which brings me to something else I'd like to address. There was
concern expressed about the early 9500 reliability, and how reliable
today's current production is.  I believe it is fair to say that Alpha had
addressed these issues before I had arrived.  The biggest source of
problems as I understand it was the band pots, and these have all been
replaced with hall effect sensors.  I'll also state that a resistor is not
always a resistor, or more clearly all resistors are not created equal.
We've had to change to brands and special resistors that don't fail in the
application.  One of them is rather pricey at 25 dollars each in hundred
piece minimums.  It isn't a flange resistor either, just a very innocent
looking leaded part that you would never know.  There is a WEALTH of
insider information that nobody knows about until you buy the company that
is the result of 30 years of building a product and learning what works and
what doesn't, and this isn't electrical engineering but material science.
All of this gets forwarded into the next go around of products.  Sometimes
in a transition of ownership some of this information gets buried, and I
believe this is some of what caused the early 9500 problems.  However, that
was over ten years ago.  Those issues were solved years ago.  If an amp
comes in for service, we check it for every update and if it isn't done we
contact the owners and advise them of that so when it does leave Alpha it
doesn't come back with a problem.  Since I've taken over, the parts bins
are overflowing with all the costly and special parts needed to build the
best vacuum tube amp possible, and that is what you get when you purchase a
new one.  Clearly I'm doing something right because we have 100%
satisfaction on the new sales and none of the repairs have been coming
back.  The only down side to all of this is it costs serious money to do
something the right way, and we HAVE to charge for it, no matter how much
we all hate it.  I believe that in any market there is always a small
percentage of people who just want to buy something that works and have the
security that it will work when you need it.  That's what I'm providing you
with Alpha and that is what you are paying for. We've been here nearly 50
years. I'm 54 years old. I intend to be around running Alpha another twenty
years if I live that long. That makes me one of the young players in this
field which means you don't have to worry about support in the future.
There has been a lot of speculation about solid state replacing vacuum
tubes.  I think both technologies have their advantages and disadvantages
as well as their time and place.  I think it speaks volumes that a solid
state manufacturer and pioneer of that technology makes that statement.
LDMOS isn't everything it is hyped up to be. It can be successfully uses in
a BROADCAST environment where all parameters like exciter level and
impedances are controlled.   Amateur radio is an environment where nothing
is controlled, especially some of the operators.
73,
Mike N8WFF

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