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5. SWR CAL CONTROL In order for you to ächieve maximum radiated po-
wer and the longest range, it is important that your antenna be in good
condition, properły adjusted and matched to your trans ceiver. The built-in
SWR (standing wave ratio) meter lets you easüy measure your antenna con
dition. To operate- this function, connect your antenna to the transceiver
antenna output connector. Select a channel near the middle p f the band
such as 21 or the channel you plan to use most frequently. Turn the power
on and set the meter function switch to the CAL position. Press and hold
the microphone push-to-talk button and using the SWR CAL control,
adjust the meter to read the CAL position indicate'd on the meter face.
Then, without releasing the microphone button, switch the meter func -
tion switch to the SWR position and read the SWR indicated. The lower
the fifgure, the better, with 1 being ideal. Generally speaking, readings up to
3 are acceptable, but over 3 indicates that you are losing radiated power and
antenna adjustment may be advisable.
6. S-RF/SWR/CAL SWITCH. When in the S-RF position, the meter swings
proportionally to the strength of the received sighal. When transmitting, the
meter indicates relative RF output power.
When in the “CAL” position, the SWR meter can be calibrated by adjusting
the “SWR CAL” con tro l to the. “CAL” mark on the meter'face.
____
When in the “SWR” position, the standing wave ratio is measured.
7. MODE (CW/FM/AM/USB/LSB) SWITCH. This switch is used to select CW,
FM, AM, LSB or USB mode of operation. Unless the station with which
communication is desired is equipped with SSB, the AM or FM mode is
normally used. The mode selector switch changes the mode of operation of
both transmitter and receiver simultaneously. Turn to “Receiving SSB
signais” for a further explanation of single sideband.
8. VOICE LOCK. Allows variation of the receiver operating frequencies above
and below the assigned frequency. Although this control is intended
primarily to .tune in SSB/CW signais, it may be used to optimize AM/FM
signais as described in the Operating Procedure paragraphs. Coarse operates
both TX/RX but Fine only in RX.
9. CHANNEL SELECTOR. This switch selects any one of the forty Citizens
Band channels desired. The selected channel appears on the LED readout
directly above the Channel Selector knob.
10. CHANNEL 9 SWITCH. Channel 9 has been reserved emergenpycommunica
tions involving the immédiate safety of life of individuals or immédiate
protection of properly. Channel 9 may also be used to render assistance to a
motórist.
11. OFF-NB/ANL SWITCH. In the NB/ANL position, the RF noise blanker is
activated and automatic noise limiter in the audio circuits is also activated.
The RF noise blanker is.very effective for répétitive impulse noise such as
ignition interférence..
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Summary of Contents for 148GTL-DX
Page 32: ...со SO AOJ VR2 BLOCK DI AGRAM ...
Page 33: ...SCHEMATIC DIAGRAM ...
Page 41: ...Parts Layout Top View Î37 2SB525C 1 4 1 5 ...
Page 42: ...PARTS LAYOUT Top View ...
Page 43: ...ADDED PARTS MAIN PCB Bottom View PC 879AB ...
Page 44: ...COPPER PATTERN SWR PCB CH SW PCB LED PCB CD ...
Page 48: ...го w INTERNAL DIAGRAM IC s MB87I9 ...
Page 49: ...INTERNAL DIAGRAM IC s го А ...
Page 50: ...INTERNAL DIAGRAM IC s S 0 4 2 P 25 ...
Page 58: ...со го BLOCK DI AGRAM ...
Page 59: ...PB OIO SCHEMATIC DIAGRAM ...
Page 60: ...WiRING DIAGRAM 3 5 3 6 P C 881 P C 8 8 0 ...
Page 66: ...COPPER PATTERN MAIN PCB ...
Page 68: ...P B O I O ADDED PARTS MAIN PCB H fs il 8 46 ...
Page 70: ...COPPER PATTERN SUB ASSY PCB s ...
Page 71: ...PARTS LAYOUT MIC JACK 49 ...
Page 74: ...INTERNAL DIAGRAM IC s MC14008B 1 4 Cou l 13 S 4 13 S 3 11 S2 10 S 1 16 15 14 13 12 11 10 9 52 ...
Page 75: ...сл С О INTERNAL DIAGRAM IC s OSC out Г 2 out FS PO PI P2 P3 PA P5 P6 P7 P8 MC145106 ...
Page 76: ...INTERNAL DIAGRAM IC s 14 0UT4 13 I N 4 12 lN 4 11 VEE 10 IN 3 9 I N 3 8 0UT3 TA75902P 54 ...