RadioShack 21-533 - Manual

5 1. Turn off your radio. Then disconnect the antenna from the radio and plug it into ANTENNA on the back of the meter. 2. Plug the coaxial cable into the radio’s antenna jack and into TRANSMITTER on the back of the meter. CALIBRATING THE METER/MEASURING SWR 1. Set CALIBRATION/FS/SWR on the front of...

8 Interpreting SWR Readings An ideal SWR reading is 1.0, but this reading is usually possi-ble only under laboratory conditions or with a dummy load. Ac-tual antenna installations have higher readings. The in-formation below will help you interpret the readings you get. SWR Efficiency Interpretation...

9 IMPROVING SWR There are several ways to improve the SWR of your radio/an-tenna combination. Try these first. • Be sure you are using the type of cable recommended for your equipment. If the manufacturer recommends a 50-ohm cable, do not substitute another type that has a dif-ferent impedance. • Co...

10 MEASURING FIELD STRENGTH Your meter can measure the low levels of radio frequency (RF)generated by a radio transmitter. You can use these measure-ments to map the transmitting direction and coverage patternof your antenna, or to compare your radio and antenna’s effi-ciency before and after an adj...

11 PREPARING THE ANTENNA SITE Before you use the meter to measure field strength, you shouldmark the site around the antenna in a pattern that will help youmake the measurement. An easy way to do this is to map the area around your antennausing a template like this one. Antenna Location 21-533.fm Pa...

17 USING FIELD STRENGTH READINGS TO TUNE YOUR RADIO AND ANTENNA You can use field strength measurements to monitor the effec-tiveness of changes you make to your radio and antenna while you make them. Changes you might make include: • Installing a new antenna or antenna cable • Adjusting the length ...

18 Then, while the helper holds down the transmit key, walkaround and adjust the meter’s knob until the meter’s nee-dle moves to 3 on the FIELD STRENGTH scale. Notes: • If you use a CB that has sideband modes (SSB), do not select any of these modes. (Use only AM for fieldstrength measurements). • If...

19 CARE AND MAINTENANCE Your RadioShack CB/Ham Field-Strength SWR Meter is anexample of superior design and craftsmanship. The followingsuggestions will help you care for your meter so you can en-joy it for years. Keep the meter dry. If it gets wet, wipe it dry im-mediately. Liquids can contain mine...

21 SCHEMATIC DIAGRAM (illus - show schematic diagram of meter) 21-533.fm Page 21 Thursday, August 5, 1999 3:47 PM

22 SPECIFICATIONS Measurable RF Power ..................................... 1–1000 WattsSWR ................................................................................ 1–3Impedance .............................................................. 50 OhmsFrequency Range ...............................

23 Limited Ninety-Day Warranty This product is warranted by RadioShack against manufacturing defects in ma-terial and workmanship under normal use for ninety (90) days from the date ofpurchase from RadioShack company-owned stores and authorized Ra-dioShack franchisees and dealers. EXCEPT AS PROVIDED...

RadioShack A Division of Tandy Corporation Fort Worth, Texas 76102 811081260A 3A8 Printed in China (continued) This warranty does not cover: (a) damage or failure caused by or at- tributable to acts of God, abuse, accident, misuse, improper or abnormal usage,failure to follow instructions, improper ...