>Bill, N6CQ/3 (n6cq@paonline.com) writes:
>P.S.: A little off topic but can anyone explain why commercial mains
>standard freq is 60Hz here but 50Hz in many other countries? Does the
>freq have to do with avoiding flicker in lighting?
Well, it is because of that genius, Nikolai Tesla. Picking a frequency for
power transmission is difficult. Lower frequencies can transform more
efficiently (with low-quality Iron cores), and can be generated with
greater efficiency. But low frequencies cause lights to flicker perceptively.
So the trick is to pick a frequency high enough so lights don't flicker,
but low enough for good efficiency.
Tesla picked 60 Hz. Other parts of world use 50 Hz. A few places have 25 Hz
power, and there are a couple of really oddball frequencies in use in various
places.
Bill Coleman, AA4LR (bcoleman@hayes.com)
>From gt5830b@prism.gatech.edu (KUNKEE,DAVID BRYAN) Thu Sep 1 18:21:45 1994
From: gt5830b@prism.gatech.edu (KUNKEE,DAVID BRYAN) (KUNKEE,DAVID BRYAN)
Subject: September VHF/UHF SKEDS
Message-ID: <199409011721.NAA29538@acmex.gatech.edu>
Hello everyone,
Once again I am interested in setting up SKEDS during the September
VHF/UHF Contest. This year the Fourlanders will be operating from
Bald Knob (4229' AMSL) in FM07WW (VA). We will be using the call
AA4S (Ron Bailey) and will have all bands 6 thru 3456 (possibly higher).
I am especially interested in UHF and higher SKEDs, but I have a lot of
time on 6 and 2 to fill as well. Drop me a note if you'd like to
arrange something.
73 de Dave, K0DI
gt5830b@prism.gatech.edu
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