Tait Orca 5000, Руководство по обслуживанию

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F - 8 7.5 mm Accessory adaptor
June 2003 IPN: M5000-00-105
7.5 mm Accessory adaptor
You can connect non-Tait accessories that
require a 7.5 mm adaptor to the Tait Orca
portable radio using the 7.5 mm accessory
adaptor (TOPA-AA-005G).
Such accessories use 3.5 mm and 2.5 mm phono
plugs with 7.62 mm spacing between them. The
speaker and microphone/PTT jacks for the 7.5
mm adaptor are shown in Figure F-4.
To connect an accessory to the Tait Orca porta-
ble radio that uses PTT in series with the
microphone, wire the accessory to a 3.5 mm
plug and 2.5 plug according to Figure F-4.
The 7.5 mm accessory adaptor differs from the
standard accessory connector in that with the
7.5 mm adaptor, the PTT signal is in series
with the microphone signal. The standard
accessory connector has separate PTT and
microphone signals. If the accessory has
function buttons, they will not work with the
7.5 mm adaptor.
The main function of the 7.5 mm adaptor is to
demultiplex the accessory’s MIC/PTT line into
two separate lines for the Tait Orca portable
radio. The adaptor also detects the presence of
the accessory speaker and turns off the radio’s
speaker.
Figure F-5 shows the circuit diagram for the
7.5 mm accessory adaptor.
When the accessory PTT switch is pressed, it
connects the microphone to the adaptor
between ground and the base of Q3 (see Figure
F-5). This pulls Q3 low turning it on. Q3 in
turn pulls the base of Q2 high which pulls the
EXT-PTT line low, enabling the transmitter.
Audio from the accessory microphone passes
through C4 to the radio’s EXT-MIC line.
When the accessory speaker is connected, the
base of Q1 is pulled high via R3 and R1,
turning it on. This pulls the SENSE-0-ACC line
low, which tells the radio to turn off the inter-
nal speaker, and only the accessory speaker is
operational. C1, C2 and C3 filter out the audio
signal, so that the voltage swing of the signal
will not turn off Q1.
Figure F-4: Plugs for the 7.5 mm accessory adaptor
7.62 mm
SPK (-)
SPK (+)
GND
MIC/PTT
Speaker jack
3.5 mm
Mic/PTT jack
2.5 mm