On Wed, 02 Aug 2006 16:50:39 GMT, "Frank's" wrote:

May I insert a few words about the Smith Chart?

During the period between 1958-59 I designed the entire antenna system and
matching harness for the World's first weather satellite, TIROS 1, which
was
launched April 1, 1960.

Four transmitters operating simultaneously on separate frequencies fed the
antenna that comprised four crossed monopoles radiating right circular
polarization from two transmitters and left circular polarization on the
other
two frequencies.

The point concering the Smith Chart is that the only tools I had for the
development of both the antenna system and the matching harness was the
Hewlett-Packard HP-805 slotted line for impedance measurements, the slide
rule
for calculations, and the paper Smith Chart to tell me where I was in the
desert. The resolution available with the Chart was sufficient to make the
system work successfully. Philip Smith was my hero.

Incidentally, the matching harness was fabricated entirely of
printed-circuit
stripline, and that was 47 years ago.

Very interesting Walt. Judging by the type of work you were involved in
you must be familiar with the classic text by: Matthaei, Young, and Jones.
I am not familiar with the HP-805, but probably because most of my
earlier lab work was concerned only with HF. I realize that slide rule,
pencil, and Smith Chart was the only way in those days. When I started
work any intense analysis was done in FORTRAN on main frame
computers. One of the hot topics I remember was mini-computers,
but never got to see one. I don't think they lasted long, since soon
after programmable desktops started to become available.

One thing I remember was a guy designing HF antenna tuners, and he
used the Smith Chart. What is interesting is that the charts were
very large, about 2 ft X 3 ft, and came in pads. Much greater
accuracy than the standard chart. I think they may have been published
by a company called K-electronics. I used to needle guys in the lab
by telling them that Smith was a ham.

I now have a nice high res pdf of the Smith Chart, but
usually use an electronic version from
the "Berne Institute of Engineering".

73,

Frank

Thanks for the nice response, Frank,

Walt