Service Manual Part 1

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The following instructions apply only to those radios with CTCSS activated and
must be carried out before any further modulation adjustment can proceed.
Refer to the T2000 Programming Manual for the CTCSS channel programming
instructions. The frequency range of the CTCSS tone is 67 to 250.3Hz.
Switch to any channel with CTCSS activated.
Close the PTT switch.
Adjust RV906, on the TCXO PCB, to set the CTCSS tone peak deviation for
±660Hz ±100Hz (±530Hz ±80Hz) [±330Hz ±50Hz] on the modulation meter.
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Close the PTT switch and set up a continuous call. This can be an LTR Repeater
Talkaround call, a Repeater Interconnect Call (RIC) or an on-channel call.
Adjust RV906 on the TCXO PCB to set the LTR code deviation to ±1kHz (±900Hz)
[±600Hz].
A The deviation meter must have a good low frequency response to avoid incor-
rect readings.
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Complete the dual point modulation and CTCSS modulation adjustments (Sec-
tion 6.4.3 and Section 6.4.4) before commencing the modulation adjustment.
Apply a 3kHz sine wave at a level of -40dBm to the microphone input.
Select a channel with CTCSS activated and close the PTT switch. If CTCSS is disa-
bled, select any channel.
Adjust RV907 for a +5kHz (+4kHz) [+2.5kHz] deviation reading on the modula-
tion meter.
Maintain the same sine wave output level and sweep the audio frequency from
300Hz to 3.3kHz.
Find the frequency of maximum ‘+’ deviation and readjust RV907 for +5kHz
(+4kHz) [+2.5kHz] deviation.
Reset the modulation meter to read ‘-’ deviation.
Slowly sweep the audio frequency from 300Hz to 3kHz. If the ‘-’ deviation peak is
found to exceed -5kHz (-4kHz) [-2.5kHz], readjust RV907 for a peak deviation of
-5kHz (-4kHz) [-2.5kHz] at that frequency.
The peak deviation should not exceed ±5kHz (±4kHz) [±2.5kHz] on any channel.