Vega DSP-223, Техническое руководство

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4 Vega DSP-223
2.3.5 Radio Frequency Control
The DSP-223 provides two relays that may be used for radio channel control. F1 and F2 contacts may
be connected through the rear DB25 connector. Usually the common of each relay contact switch is
grounded and the normally open contact connects to the radio frequency-control terminals.
In addition to the two standard relay closures, six lines of digital I/O are available. These lines are open-
collector transistor outputs. They can be programmed on a per line basis to generate any of 64
combinations. A programmed option is also available that does not change the digital I/O.
Each line is active low and may be jumper selected to pull up to 5v or the power supply voltage
(m12v). Jumper J16 is used to select the pull up voltage. The A position pulls to the power
supply value and B pulls up to +5v.
Refer to Section 4.2.2.9.5 Digital Output for programming the digital outputs.
2.3.6 CTCSS Connection
The DSP-223 is designed to generate a full range of CTCSS frequencies. Each function tone can be
assigned its own CTCSS frequency for PTT operation or a number of CTCSS tones can be set using
different function tones. A single ended, capacitor coupled, low impedance output is available on pin 11
of the rear panel DB25 connector.
2.4 Handset Connection
The Telex Handset (P/N 249248) may be connected to the DSP-223 to monitor receive and transmit
audio. When the handset PTT switch is pressed, the DSP-223 will be key up the radio on the existing
frequency and the handset microphone audio will be transmitted.
Pressing the PTT-IC button on the front panel provides an intercom connection between the DSP-223
and the tone remote console.
2.5 Digital Expansion Port
The Digital Expansion Port on the rear panel of the DSP-223 provides a second serial communications
connection for use in controlling various base station radios. A plug-in serial add-on PCB must be
installed to enable this connector. This port is configured as a function of the specific application and the
data is restricted to the control of specific radios. It is not intended as a general communications port to a
PC.