ZETRON 025-9623 D3, Руководство пользователя

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Configuring Console Audio Levels
23
7. The Talkgroup List is used to configure aliases for the Talkgroups. Talkgroup
aliases configured here are displayed at the console.
8. Click the Submit button. This will return to the View/Modify Configuration
page.
!
Caution! If any changes were made to the channel parameters they
have not been saved yet.
9. The previous steps may be repeated for Channel B. Click the Channel B
Parameters button. This will bring up the Channel B Configuration Page .
10. Click the Save Changes button. This saves the new configuration to the iRIM’s
non-volatile memory. The previous configuration is also preserved.
Configuring Console Audio Levels
This section provides additional detail for step 5 from the preceding procedure. The three
settings of interest are Peak Level From Console , Audio Level From Console , and
Audio Level To Console . The settings are in units of dBm, where 0 dBm is equivalent to
0.775 VRMS.
Peak Level From Console defines the maximum audio level, and where clipping occurs.
The iRIM assumes the loudest tone from the console is the high-level guard tone. It bases
its AGC calculations on this being the loudest tone. The level for the HLGT should be
less than the Peak Level From Console .
Audio Level From Console
defines the level of the average voice audio from the
console. Audio received by the iRIM from the console at this level is transmitted over the
air at 60% deviation on an analog broadcast. If the voice audio over the air sounds too
quiet, this setting should be decreased; if the audio is too loud, it should be increased.
Audio Level To Console defines the level of the average voice audio received by the
radio. Audio received by the iRIM from the radio is transmitted to the console at this
level on average.
The following example assumes that the console system is properly calibrated. Between
the iRIM and the console is a bearer with an unknown amount of loss, which needs to be
compensated for:
1. Connect a true RMS AC voltmeter to the transmit audio input pair from the
console to the iRIM. (For the pinout, see
Table 3
on page
17
.)
2. Transmit a test tone from the console that is intended to produce 60% deviation
over the air; it may be a 1 kHz alert tone. Measure the level of the signal at the
iRIM. (An example: the console’s 1 kHz alert tone with the HLGT set to 0 dBm,
with no line loss between the console and the iRIM, should be about -6 dBm.)
This measurement will be used in Step 7 .