[BC] Re: Design Engineer TE-1 & VP50

[Thomas G. Osenkowsky]

>In a message dated 5/18/05 12:05:10 PM Central Daylight Time,
>broadcast-request at radiolists.net writes:
>He's also the same guy who gave us the TE-1 FM exciter and
>the VP-100, so I'll make no further comment and let that speak for itself.

We all have favorite things to complain about from the past. I have
one 1969 phasor design which predicted an operating impedance
for one of three towers (day mode) of -50.1+j235.5 A moment
method calculation based on measured self and mutual impedances
derives the correct value of -2000+j1220.

A well known classic text on directional antennas contains calculation
errors for vertical form factors and operating impedances. Many AM DA
designs are inefficient and difficult to maintain. In the early days of jet
aircraft many were lost due to poor design and improper construction
techniques.

We may feel that more could have been done to produce greater accuracy,
better designs and increased reliability. Hindsight is 20/20. We all can sit
back in our comfortable chairs and criticize, say "should have" or "could
have" and the like. Let's bear in mind that we have become so used to
computer modeling, CAD, modern instrumentation and devices and
techniques that the engineers who we criticize today could not have
dreamed of in their day. Math calculations were performed by hand, or
slide rules. It takes a computer less than a second to perform a complete
set of VF factors whereas in the 1940's it took hours by hand. No Moment
Method, circuit analysis and matrix calculations. Schelkunoff modernized
impedance calculations far above sinusoidal methodology. Computer
modeling has allowed us to predict faults, operating parameters and
conditions with great accuracy.

Many of the early designers are long past. Before casting stones upon
them let's just step back and wonder who may be doing the same to us
in fifty years. Bear in mind this is coming from someone who has dealt
with the arrays and equipment mentioned herein.

Tom Osenkowsky, CPBE