Processors are cheap and reliable. I can remember when I had to content with
reliability issue in 1980 when at Turret Equipment Corp I have designed the
First Key Telephone System using solid state switching and processors.
At the time everybody said it will never work as the processors are not
reliable enough ... Today we can not even imagine _any_ communication
system without at least one processor.
There are 4 processors/microcontrollers in our Amplifier. The SAM (System
Ambient Monitor)processor is a $2 PIC that provides more intelligence that
some people on this list have. It monitors temperature, air flow and
humidity in 28 places in the amplifier/PS/Antenna Tuner assembly.
The second processor (PC for Power Controll) is a Motorola power house you
can get for $6. It controls the automatic load tuner, the SWR and FORWARD
Power Samplers and the filament and anode voltages in real time. Together
with SAM, HF arching is totally impossible
The third one, DC - Display Control- is an 8751 ($3) controlling the
Analog/Digital and/or CRT displays.
The forth is a Rabbit Semiconductor 3000 ($12) as a System Control,
Communication and Supervision.
The CCS processor allow multiple Amplifiers to be networked and controlled
from a remote location :) - besides other nice features like signal
distortion monitoring/comparison through FFT (Fast Furier Transform) on the
input/output signals .
And all of this for less that $50 and some time in programming it. Don't you
think is worth it ? The customers are not stupid when they ask for it :)
One might ask why four if one should suffice. The answer is that the system
is modular every module having it's own controller. This makes the Amp easy
to configure and/or add new features.
My car has 8 processors. Why is it that my amplifier should not have four ?
Darwin has shown that evolution means growing intelligence. Why should it be
different for any equipment we build, including amplifiers? You want to
progress, to evolve your designs, don't you ? And progress in our Amps
means, processors, logic, ram, flash and so on.
About noise. Only CHEAP Fans make noise. FANS DO NOT MAKE NOISE! AIR
MUVEMENT DOES :)
About surface machining to 100A. The process is called molecular bonding and
it actually embeds the transistor in the cooper heat spreader. It is not my
fault you
have not heard about it inspite the fact that Motorola has pioneered it 30
years ago :)
Wake up. 30 years ago one Bill OR has designed one AMP and you are still
copying it! No wonder the Japanese (and others) have taken our markets :(
Start thinking independently, make some waves, produce something new ...
30 years wasted ... oh...
Alex
> -----Original Message-----
> From: Tom Rauch [mailto:w8ji@contesting.com]
> Sent: Tuesday, July 23, 2002 6:07 AM
> To: dhearn@ix.netcom.com; alex
> Cc: amps@contesting.com
> Subject: RE: [Amps] Muffin Fans and hot exhaust/2
>
>
> > In 2xMR154 module, I use two 48V/145CFM Fans from Mechatronics. They
> > are PWM controlled by the microcontroller and mounted on the top of
> > the finned part of the heat sink. A third fan 100CFM is right on the
> > top of the output transformer and it is controlled by the same
> > controller as the first two.
>
> Three fans and a microprocessor to cool one heatsink and one
> transformer. Talk about exaggeration!
>
> > This arrangement keeps the die at only 120C forever when running full
> > 1500W.
>
> So would a single fan with no CPU.
>
> > About noise. The more noise your fan is doing the better you are off
> > as it is an indication of air movement . If you want a quiet Fan you
> > will have to reduce the amount of heat generate and implicitly your
> > output power. Certain Thermodynamics laws can not be circumscribed :)
> > FANS DO NOT PRODUCE NOISE! AIR MOVEMENT DOES!
>
> In fact most noise is caused by bearings in the fan, turbulence in
> the impeller, and at times from turbulence in the device the air is
> forced through. Some fans and blowers have poor balance, but that
> mostly causes a low rumble.
>
> There can be a tremendous difference in noise at the same airflow.
> One example is the Ten Tec 811A amplifier, where they unwisely
> stuffed the muffin fan against large objects. This increases noise
> drastically and reduces airflow significantly. A fan or blower will
> generally become noisier when airflow is restricted.
>
> 73, Tom W8JI
> W8JI@contesting.com
>
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