15
25A1090 (Rev.3)
FREQUENCY ALIGNMENT:
1. Set the transmitter to MID frequency (see table on page 14).
2. Connect the 50 Ω cable to a frequency counter.
3. Adjust variable capacitor CV501 until the frequency counter measurement matches the
appropriate frequency on the table below, ± 1 kHz. .
RF OUTPUT POWER
The output power measurement ensures that the output signal is strong enough for
sufficient range when the system is in use. The output power measurement also verifies
tha the output power is not above the specified maximum level, to ensure compliance
with regulatory angencies’ standards.
1. RF output power is only adjustable on and JB units. Use RG58 (PT 1824) or any other low
loss 50 Ω cables for all RF connections.
2. Include the insertion loss of the cables and connectors in rf conductive power measure-
ments.
3. Connect the RF output of the transmitter to a spectrum analyzer.
4. Set the spectrum analyzer center frequency to match the transmitter frequency.
5. Using a power meter or spectrum analyzer, verify the output power matches the range
indicated in the table below. JB models can be adjusted at TR640.
6. Remove the BNC to unterminated test cable (PT1824) and replace L641 to reconnect the
antenna.
DEVIATION ADJUSTMENT
Deviation must be set to make sure the companding systems between the transmitter and re-
ceiver correctly track each other. The level coming out of the transmitter’s audio compressor
must match the level going into the receiver’s audio expander. A fixed gain structure does not
ensure exact match, primarily because of variations in voltage-controlled oscillators (VCO’s).
USING A SLX4 RECEIVER
The following procedure requires a SLX4 receiver. It is recommended that a properly tuned
receiver be used to perform the transmitter deviation adjustment.
GROUP CODE FREQUENCY RANGE
H5 529.500 Mhz ± 1 kHz
J3 583.500 Mhz ± 1 kHz
JB 807.500 Mhz ± 1 kHz
L4 649.500 Mhz ± 1 kHz
P4 714.000 Mhz ± 1 kHz
Q4 746.325 Mhz ± 1 khz
R5 810.275 Mhz ± 1 kHz
S6 851.300 Mhz ± 1 kHz
GROUP Pout RANGE
H5 14 dBm ± 2 dB
J3 14 dBm ± 2 dB
JB 7.0 - 10.8 dBm
L4 14 dBm ± 2 dB
P4 14 dBm ± 2 dB
Q4 10 dBm ± 2 dB
R5 13 dBm ± 2 dB
S6 10 dBm ± 2 dB
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