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[AMPS] Big Bang Problem

To: <amps@contesting.com>
Subject: [AMPS] Big Bang Problem
From: ki7rw@arrl.net (Lee Roberts)
Date: Sun, 05 Mar 2000 13:36:22 -0700
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Based on this criteria, what amps are recommended? And can any of those 
handle 100% duty cycle (such as for RTTY) for at least 30 minutes?

At 11:28 AM 3/5/00 -0800, you wrote:

You hit the nail on the head, Phil. Excellent summary.
- -------------------------------------------------------

Allow me to suggest several factors that have exacerbated
the "big bang" problem over the years.

!. The scaling down problem. Sacrificing fair to good layouts
    for a more compact product with less robust components.

2. Going from 5 bands to 8 or 9 in a very small box is a tremendous
     feat in itself. This presents a very large invitation to disaster.
     Components and their layout become many times more critical.
     Going from 5 band Pi networks to 8-9 band Pi-L networks,
     usually in the same space or less has created a great dumbing
      down of design. One cannot blame manufacturers for this entirely.
    The "modern" ham is demanding a legal-limit, all-band amp that
    can be carried home under one arm, and God help the manufacturer
    who provides a blower that is any louder than a field mouse
    urinating on a cotton boll.

3. Ever-rising requirements for higher plate voltages in the newer
     generation tubes now on the market, while still maintaining
     cabinet size where 2000-2500 volts previously resided. Going
     from 3000volts to 5000-6000 volts Ep  is not a linear increase in
     design criteria; it is exponential.

4. Starting with Drake et al, producing exciters with power over-shoot
     at key-up, combined with QSK, VOX and the popularity of the
     digital modes have created new means to punish amplifiers at
     each mash of the key.

5. Although most hams may be willing to pay $40,000 for a new Ford
     truck, they began to balk in the mid '80's about paying for tank
coils
     wound with big tubing, vacuum variable capacitors, power supplies
     with one oil filter capacitor,  tuned filter chokes, and 20 amp band
     switches.

The amp problem is not unique in the U.S. market place. One law of
economics that still remains in place is that you usually get what you
pay for.

(((73)))
Phil, K5PC

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