TM-9-2350-275-BD Battlefield Damage Assessment and Repair for M113 Family Download
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TM 9-2350-275-BD APPENDIX B FIELD EXPEDIENT TEST EQUIPMENT (CONT) 2. Making an Ohmmeter (continuity tester). An ohmmeter can be made from a flashlight bulb, flashlight battery, and three pieces of wire. When the free ends of the wires are touched to a circuit where continuity (or a short) exists, the bulb will glow. If a two-cell flashlight bulb is used with only one battery, the bulb will glow with one-half its normal brilliance. 3. Making an RF Transmitter Output Tester. This device is used to determine if the radio is sending a signal to the antenna. a. An RF transmitter output tester can be made from a neon light bulb and a piece of CG-1773 RF cable. Solder the bulb to the cable as shown in the illustration. Connect the cable to the ANT connection on the f rent of the radio. When the radio is keyed, the bulb will glow if RF power is present at the antenna connection (this does not verify transmitter frequency accuracy). b. Another way to check for transmitter output is to hold a common (wood) lead pencil tip l/4-inch to l/8-inch from the ANT connection. If RF power is present, a yellowish-white arc will jump from the connector to the pencil tip when the radio is keyed. B-8