TM-9-2350-273-BD M60 M48 Battle Damage Assessment and Repair Download
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TM 9-2350-273-BD COMMUMCATIONS SYSTEM Procedural Steps (Cont'd) h. Turn the POWER SWITCH (23) and the DIAL LIGHT SWITCH (26) to the on (up) position. At this time the FREQENCY DIAL VIEWING WINDOW (5) and the INDICATOR METER (12) will light. After the tubes are heated, a rushing noise will be heard in the earphones. Adjust the VOLUME CONTROL KNOB (16). for the desired volume level. Check the power supply in the receive mode by noting the reading on the INDICATOR METER (12) and turning the VOLTAGE CHECK/OPERATE SWITCH (28) clockwise to the 6,3B and the 150B positions. The needle on the INDICATOR METER (12) should be in the shaded portion of the scale for all three readings. If not in the shaded portion, check the power supply for bad fuses and replace any bad ones. CAUTION The receiver and transmitter are tuned simultaneously. Do not operate the transmitter without using an antenna or dummy load. Transmitting into an antenna base without connecting an antenna may damage the transmitter portion of the radio. j = Check the power supply in the transmit mode by placing the VOLTAGE CHECK/OPERATE SWITCH (28) to the 1,2B position on the transmitter circuits portion of the scale (approximately the 7 o’clock position). The INDICATOR METER (12) should read in the shaded portion of the scale. If not in the shaded portion, check the power supply for bad fuses and replace any bad ones. k. Place the VOLTAGE CHECK/OPERATE SWITCH (28) in the 150B position by rotating the switch clockwise. Momentarily place the chest plate switch and the CVC helmet or H-189 switch in the transmit position. Note the reading on the INDIATOR METER (12~ it should be in the shaded portion of the scale. Release the switches. 1. Place the VOLTAGE CHECK/OPERATE SWITCH (28) alternately in the 250B and 600B positions by rotating the switch clockwise. To obtain an indication, it is necessary to momentarily depress the switches to transmit. Both the readings should be in the shaded portion of the scale. . Place the VOLTAGE CHECK/OPERATE SWITCH (28) in the operate # 1 (PAbOTA 1) position. n. Place the PRESET CHANNEL/CONTINUOUS TUNE SELECTOR SWITCH (18) in either the I or II position. Position I will be used if the desired operating frequency is between 20 and 35.75 MHZ and position II will be selected if the desired operating frequency will be between 35.8 to 51.5 MHZ. Band selections are also shown by the BAND INDICATOR (13) lights. 11-35