That elusive DB just reared it head at Jamesburg. We discovered that our
dish has neither parabolas, or hyperbolas as part of normal Cassegrain
surfaces. Mike Brenner, our laser metrologist just determined that the
dish, built by Philco Ford in Late 60s, probably designed in early 60s was a
tweaked design that had reshaped both surfaces to gain only about 1 db more
in the 63 dbi gain dish.
I dont know why they went to all the trouble to do that to just get one more
DB to listen to Geosynchronous Satellites.
But a more interesting question, in light of the fact that this was WAY
before the HP 35 was around , (;>) in fact in the REAL olden days,
Engineers used slide rules, and surveyors used 8 place trig and Logarithm
tables. Logsin A minus Logtan B plus...oops...
Anyone here from that era who might know if such a dish required the
computation horsepower of a mainframe of the time, to design and build?
Say a bunch of Fortran Punch Cards and an IBM 360?
Sincerely, Pat Barthelow aa6eg@hotmail.com
http://www.jamesburgdish.org
Jamesburg Earth Station Recovery Team
>From: "Roger (K8RI)" <K8RI-on-TowerTalk@tm.net>
>To: <towertalk@contesting.com>
>Subject: Re: [TowerTalk] the elusive 1db
>Date: Tue, 15 May 2007 17:07:37 -0400
>
>
>
>
> >> A difference of only 1 db is all but unnoticeable.
> >
> >> Bill W6WRT
> >
> > I wish I had that 1dB when listening for BS7H on 20m from the east coast
>2
> > weeks ago....
>
>It'd be real handy when working Aurora on 6 when the signals don't even
>show
>above the band noise on a scope too <:-))
>
>73
>
>Roger (K8RI)
>
> >
> > John K5MO
> >
> > _______________________________________________
> >
> >
> >
> > _______________________________________________
> > TowerTalk mailing list
> > TowerTalk@contesting.com
> > http://lists.contesting.com/mailman/listinfo/towertalk
>
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