Tait Orca 5000, Руководство по обслуживанию

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F - 6 Tait Orca 5000 accessory connector
June 2003 IPN: M5000-00-105
Accessory connector signal
descriptions
RX-DET-AF-ACC
The RX-DET-AF-ACC line carries unprocessed
receive audio from the output of the detector IC.
MOD-AUDIO
The MOD-AUDIO line is used during calibra-
tion to set up the modulation balance and by
some accessories, such as modems.
+7V5-ACC
The +7V5-ACC line su7.5 V to accesso-
ries and is limited to 20 mA maximum. The
output voltage itself will change depending on
the battery voltage level, and there will be
some voltage differential between the battery
voltage and 7V5-ACC, depending on the
current drawn by the accessory.
RXD-ACC
The RXD-ACC line carries data from the acces-
sory connector to the controller during tasks
such as radio programming and calibration.
TXD-ACC
The TXD-ACC line is a digital data line from
the microprocessor and carries synchronous
data from the controller to the accessory
connector during tasks such as radio program-
ming and calibration.
SENSE-0-ACC
SENSE-0-ACC is used to turn off the radio’s
internal speaker. To turn off the internal speaker,
tie SENSE-0-ACC to GND by shorting link 1
(LK1). The external speaker outputs are always
active.
SENSE-1-ACC
On conventional radios, SENSE-1-ACC is an
output which follows the squelch detect line.
On trunked radios, SENSE-1-ACC is a currently
unused input.
EXT-MIC
The EXT-MIC signal is an analogue input from
the microphone of an accessory.
Connecting a microphone to EXT-MIC
automatically turns off the radio’s internal
microphone.
EXT-PTT
The EXT-PTT is an analogue signal from the
accessory interface to the control area and
indicates an external request for PTT and
external function buttons.
GND
The GND pin is the ground point of the acces-
sory connector.
BUTTON-1 and BUTTON-2
Two external accessory function buttons are
available, BUTTON-1 and BUTTON-2.
The sensing of the external function buttons is
determined by a voltage divider on EXT-PTT.
This consists of a 27 k
Ω
pull up to 5 V inside
the radio and a pull down resistor on the acces-
sory PCB. The resistor pull downs for
BUTTON-1 and BUTTON-2 are as follows:
■
PTT function: resistor pull down 0
Ω
,
voltage level on EXT-PTT is 0 V;
■
BUTTON-1 function: resistor pull down
12 k
Ω
, voltage level on EXT-PTT is 1.5 V;
■
BUTTON-2 function: resistor pull down
27 k
Ω
, voltage level on EXT-PTT is 2.5 V.
These resistors are already fitted to the acces-
sory PCB.
EXT SPKR +/–
The EXT SPKR +/– line can be used to drive an
external speaker. Neither terminal should be
grounded, as the output is differential.
RF
This pin provides a connection for accessories
requiring RF, such as the RF speaker micro-
phone. When an RF accessory is connected,
the main antenna is switched out.