© 1996 Tandy Corporation.
All Rights Reserved.
RadioShack is a trademark used by Tandy Corporation.
Cat. No. 20-006A
Telescoping Antenna for Portable Scanners
and Walkie Talkies
You can use this telescoping antenna for either receiving or transmitting. You can
use it as a
receiving
antenna from 25 MHz through the 1296 MHz Ham Band, and
you can use it as a
1
/
4
wavelength
transmitting
antenna from 130 MHz through 535
MHz.
USING THE ANTENNA FOR TRANSMITTING
For transmitting, you must set the antenna length as close as possible to the trans-
mitting frequency’s
1
/
4
wavelength. This ensures the best possible transmission by
using the proper standing wave ratio (SWR).
Cautions:
• When you use the antenna to transmit, you must always collapse the section
located just above the loading coil. If you do not, you might damage the
antenna and/or your radio.
• When you use the antenna to transmit, you must calculate the
1
/
4
wavelength
and adjust the antenna length accordingly. If you do not do this, you can dam-
age your transmitting equipment due to an improper standing wave ratio
(SWR).
Use this formula to calculate the proper length for a
1
/
4
wavelength transmitting an-
tenna:
2834
Freq. in MHz
=
Antenna Length in Inches
Example: 2834
147 (MHz) =19.3 Inches
20-006.fm Page 1 Tuesday, August 3, 1999 2:25 PM
