Icom IC-718 Instruction Manual - Page 31

5 RECEIVE AND TRANSMIT ï Optional AH-4 AUTOMATIC ANTENNA TUNER operation The AH-4 matches the IC-718 to a long wire antenna more than 7 m/23 ft long (3.5 MHz and above). • See p. 14 for connection. • See the AH-4 instruction manual for AH-4 installa- tion and antenna connection details. TUNER OPERATION Tuning is required for each frequency. Be sure to re-tune the antenna before transmitting when you change the frequency-even slightly. AH-4 setting example: For mobile operation Optional AH-2b antenna element For outdoor operation Long wire AH-4 IC-718 MODE FILTER TS PWR AF SQL RIT SHIFT MIC PHONES LOCK ˛ V/M1 A=B2 A/B3 MW4 M=C5L M V6 SP7L SCN8 VOX9 .NR ANF0 FE-INNPT NB COMP SET P.AMP ATT TUNER CH DN UP∫ R WARNING: HIGH VOLTAGE! NEVER touch the antenna element while tuning or transmitting. • Tuner type setting (p.46) q Push [PWR] for 1 sec. to turn power OFF. w While pushing and holding [SET], push [PWR] to turn power ON. e Push [UP Y] or [Z DN] one or more times to select [TUNER]. r Rotate the main dial to select "4". • AH-4 AUTOMATIC ANTENNA TUNER is selected. y Push [PWR] for 1 sec. to turn power OFF. u Push [PWR] to turn power ON again. • MANUAL TUNING q Set the desired frequency in an HF band. • The IC-718 will not transmit outside of the ham bands, the AH-4 tuner will tune all frequencies 3.5 to 30 MHz. w Push and hold [TUNER] for 1 sec. • " " blinks and "CW" appears while tuning. Y ∫ NEVER operate the AH-4 without an antenna wire. The tuner and transceiver will be damaged. NEVER operate the AH-4 when it is ungrounded. Transmitting before tuning may damage the transceiver. Note that the AH-4 cannot tune when using a 1⁄2 λ long wire or multiple of the operating frequency. Y [TUNER] e" " lights constantly when tuning is complete. • When the connected wire cannot be tuned, the " " goes out, the AH-4 is bypassed and the antenna wire is connected to the antenna connector on the transceiver directly. r To bypass the AH-4 manually, push [TUNER]. Tuning indicator; Blinks: Tuning now Appears: Tune is completed Disappears: Tune is not completed CONVENIENT • PTT tune function The AH-4 is always tuned when the PTT is pushed after the frequency is changed (more than 1%). This function removes the "push and hold [TUNER]" operation and activates first transmission on the new frequency. This function is turned ON in initial set mode (p. 46). 29