TM-9-2350-273-BD M60 M48 Battle Damage Assessment and Repair Download
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TM 9-2350-273-BD COMMUNICATIONS SYSTEM Procedural Steps (Cont'd) t. Set the PRESET CHANNEL/CONTINUOUS TUNE SELECTOR SWITCH (18) to the preset #1 position. u. Set the PRESET CHANNEL BAND SELECTOR (11) to correspond with the desired band. Frequencies between 20.0 and 35.75 MHZ are set on Band I (switch up); frequencies between 35.8 and 51.5 HMZ are set on Band 11 (switch down). Band selections are indicated by the BAND INDICATOR lights (13). v. Open the PRESET LOCKING SCREW ACCESS COVER (19) on the front panel and loosen the PRESET LOCKING SCREW (6) marked "1“ by turning the locking screw counterclockwsie until the slot is at right angles with the red circle. To release the preset locking screw, use the special key (not shown) attached to the case of the radio. w. Turn the FREQUENCY TUNING CONTROL KNOB (27) to the desired frequency by aligning the desired frequency with the indicator line within the FREQUENCY DIAL VIEWING WINDOW (5). While holding the FREQUENCY TUNING CONTROL KNOB (27) turn the PRESET LOCKING SCREW (6) clockwise with the special key until it is aligned with the red circle. x. Loosen the ANTENNA LOADING CONTROL LOCKING NUT (8) two or three turns counterclockwise. . Put the chest plate switch in the transmit position and hold. Turn the ANTENNA LOADING CONTROL KNOB (9) for maximum deflection on the INDICATOR METER (12) and maximum brilliance on the RF INDICATOR LAMP (7). NOTE Several peaks will be noted on the indicator meter while loading the antenna. Tune to the maximum peak and to the maximum brilliance on the indicator lamp. For a more sensitive meter to help chooose between peaks, turn the VOLTAGE CHECK/OPERATE SWITCH (28) to the operate #2 (PAbOTA 2) position. After determining the most advantageous loading position, return the VOLTAGE CHECK/OPERATE SWITCH (28) to the operate #1 (PAbOTA 1) position. Release the chest plate switch. z. While holding the ANTENNA LOADING CONTROL KNOB (9), tighten the ANTENNA LOADING CONTROL LOCKING NUT (8). Check this step by depressing the chest plate switch to the transmit position. If the indication on the INDICATOR METER (12) is not the same as noted in step (y), loosen the ANTENNA LOADING CONTROL LOCKING NUT (8) and repeat step (y). If proper loading has been accomplished release the chest plate switch and proceed. 11-37