GAI-Tronics MRTI 2000 (No. PL1877A) Microprocessor Radio Telephone Interconnect Installation & Service Manual - Manual (Page 31)

PL1877A Microprocessor Radio Telephone Interconnect PC Programming
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Installation
Installation – Radio Interface Parameters
These parameters must be set:
RX Audio Source
Allows the installer to match the RX audio source. Choices are Detector/Discriminator audio, prior to
de-emphasis, or from Speaker audio, after the de-emphasis circuit.
Use of the internal noise-operated squelch circuit requires the audio source be derived from the detector
(or discriminator). Select Detector/Discriminator audio.
Use of the RX audio VOX for carrier detect requires speaker (muted) audio for its source. Select
Speaker audio.
RX Audio Input Level
Allows the installer to match the available receive audio level.
High level discriminator/detector is 0.45 V
RMS
+/−8 dB.
Low level discriminator/detector is 80 mV
RMS
+/−8 dB.
High level speaker is 2.5 V
RMS
+6 dB to –8 dB.
Low level speaker is 0.45 V
RMS
+/−8 dB.
Carrier Detect Source
Determines the method for carrier detection.
• Use of (noise operated) Internal Squelch requires discriminator detector audio.
• Use of RX Audio VOX requires that the source of receive audio is muted i.e., speaker audio. The
external logic carrier detect also requires that the polarity match the radio's logic carrier detect
output. Some radios require internal jumper changes to select the RX audio source - discriminator or
speaker audio. Refer to the radio manual for specific help on jumper settings.