ADJUSTMENT PROCEDURE
5-4
December 1997
Part No. 001-7500-001
VHF ADJUSTMENTS
Figure 5-3 VHF Adjustment Points
5.3 PLL ADJUSTMENT (VHF MODELS)
1. Connect a DC voltmeter probe to check point CP1
as shown in Figure 5-3 (access it by removing the
rubber option cover if applicable). Select the chan-
nel on the high end of the band (150.000 or 174.000
MHz). With the computer setup, this is done by
pressing the
↑ ↓
arrow keys to highlight “Memory
CH” and then pressing the adjust keys (
←
/
→,
PgUp/PgDn, or spacebar/backspace) to select the
channel.
2. Key the transmitter and adjust L11 (see Figure 5-3)
for a meter reading of 3.0 volt (LB) or 4.3 V (HB).
NOTE: “LB” refers to Low Band 136-150 MHz
models, and “HB” refers to High Band 146-174
MHz models.
3. Unkey the transmitter and the meter reading in the
receive mode should be 2.2 – 3.2 volts (LB) or
3.1 – 4.1 volts (HB).
5.4 TRANSMITTER ADJUSTMENTS (VHF
MODELS)
5.4.1 REFERENCE FREQUENCY
1. Select the channel on the low end of the band
(136.000 or 146.000 MHz).
2. Scroll down to “TXF SET” and press (Enter). Mon-
itor the transmit signal with a frequency counter.
3. Key the transmitter and adjust for the displayed fre-
quency by pressing the adjust keys. Unkey the
transmitter.
R150 (DTCS Waveform Adjust)
R92 (Squelch Adjust)
Mic
Spkr
Attach an RF
Connector Here