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ARRL Products:
Space/Satellites(More)
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The ARRL Satellite Handbook -- First Edition. Explore, track and operate ham radio satellites!
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Feedback - October, 2003 QST
In "The Doctor is IN" (Aug 2003, p 53), we
should have pointed out that the formula for the LC constant should be used
with L in µH and C in µF (not H and F) in addition to f in MHz.--tnx Robert
Crupi, NA6H
In "Hands-On Radio" (Mar 2003, p 64), the
first sentence of the caption for Figure 1 should read "The common collector
circuit," not "...common emitter..." It is, of course, an emitter-follower circuit
and we labeled it incorrectly.--tnx Galen Tustison, W4WET
In "Solid-State Those Panel Lamps" (Sep 2003,
pp 38-39), we neglected to talk about reverse voltage protection for the LEDs
when operating from an ac source. The diode will be subject to about 9 V peak,
when operated from a 6.3 Vrms ac source. LEDs will normally have a
PIV rating of anywhere from 5-10 V and a back protection diode placed in series
with the LED will ensure against premature failure. Another LED, back to back,
in series with the first, will also work and both will then light on ac. Of
course, if you are running these on dc, there's no problem.--tnx Roger
Wagner, K6LMN
Page last modified: 01:18 PM, 29 Aug 2003 ET
Page author: qst@arrl.org
Copyright © 2003, American Radio Relay League, Inc. All Rights Reserved.
