Tech Forum
Why is this?
Kevin Harris
St. Louis, MO
Actually, 29 MHz is assigned to
Amateur Radio. If your equipment
was actually operating on that
frequency, it was probably
manufactured in China or SE Asia
and would be considered illegal
to operate.
Probably it was a typing error;
49 MHz is considered a walkie-talkie
and/or RC frequency of cars, boats,
or planes.
Since the power output of RC
transmitters assigned to that
frequency are quite low, probably the
car's shield has a lot to play in the
attenuation of your signal.
I would suggest obtaining a
quarter wave mag mount antenna
(234/49) feet or about five feet long
placed on top of your car. Connecting
the opposite end of the coax to your
RC transmitter should improve the
field strength greatly.
Theodore Turk
Euclid, OH
C om plete M achining C enter
Precision Laser, W aterjet,and Plasm a C uttings
www .iitm etalfab.com
[#08051 - August 2005]
I do telephone interviews (and
have permission of the other party
to record them). I need a phone
patch circuit for a cell phone to get
audio out at standard audio mixer
levels that I can record via a
laptop/computer sound card or
cassette.
Clyde
via Internet
#1 There are several commercially-available devices that allow audio
connection in to and out of cellular
phones. For example, JK Audio
makes a "Cell Tap" www.jkaudio
.com/ celltap.htm
There are also many DIY "phone
tap" circuits and projects published
on the internet. Many of these can be
found in amateur-radio ("ham")
contexts.
Circle #107 on the Reader Service Card.
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NUTS & VOLTS
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Richard Crowley
Hillsboro OR
#2 Clyde can do what he wants
with a RadioShack product. Catalog
#17-855 is a Wireless Phone
Recording Controller for $24.99 The
unit has the 2.5 mm plug to the cell
phone/wireless phone and a 1/8 plug
to go into a recorder. There is a jack
for a headset to monitor and talk with
on top. Runs on two AAA batteries.
Rod Hogg
Scott City, KS
JOB OPPORTUNITY
Nuts & Volts is looking for a senior editor
to work out of their southern CA office.
Must be an active hobbyist, have expertise
in current electronic and robotics
technologies, and excellent writing skills.
Send complete resume with current
compensation to publisher@nutsvolts
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phone calls please.
92
Circle #115 on the Reader Service Card.
SEPTEMBER 2005
