Description

FEATURES

• Full duplex to 1200 bps
• Asynchronous RS-232/V.24
• 4-wire, full duplex private line
• 2-wire, half duplex private line
• 900 Hz soft carrier turn off
• Anti-streaming
• Standalone or rack mount
• PC card rack model (PC supplies power and ground only)
• High stability transmit and receive frequency
• Ruggedized for full temperature range -40 to +75C
• Quiet multi-layer board
• Fully compatible with other asynchronous V.23 modems
• 120, 220 VAC, 12, 24, and -48VDC options

DESCRIPTION

The V.23 modem operates at 0 to1200 bps asynchronous, with FSK modulation, 2-wire or 4-wire over non-switched dedicated lines. It uses the latest DSP modem circuitry to insure excellent performance and future availability. It has 900 hz soft carrier turn off for multidrop and an anti-streaming option.

The V.23 modem is avaiable in 7.25” half card size, standalone and custom OEM board configurations are available. The pc card uses the internal PC ISA bus only for power from the pc bus. The PC card fits into a 20 slot rack mount chassis that is only 7” high. The phone line connector is an RJ-11 for 4-wire leased line operation. Transmit is on positions 2 and 3, receive 1 and 4 of the 4 position RJ-11connector. The modem has a push/push switch for local digital loop on or off. The loopback switch is located on the rear of the unit, next to the DB-25 terminal connector.

This modem is compatible with other asynchronous V.23 modems, and features high stability transmit and receive frequency circuitry, and a large dynamic range.

SPECIFICATIONS

General

Modem

• Analog half or full duplex, 2-wire or 4-wire, 600 ohm balanced
• Frequency Shift Keying:
  Mark-1300 hertz, space-2100 hertz at 0 to 1200 bps asynchronous
• Transmit level control 0 dBm or -16 dBm
• Receive sensitivity is 0 to -42 dBm

• Will drive up to 30 Km of cable depending upon wire gauge
• Switched carrier or constant carrier operation (RTS forced on or terminal controlled)
• V.23 modems will communicate with military l1TADILB modems configured in V.23 mode, however they will not interoperate if the L1TADILB modem is in Link 1 mode

Digital Interface

• RS-232/V.24, DB-25S
• Signals are Tx, Rx, RTS, CTS, DSR, DCD
• RTS/CTS delay in switched carrier mode is 40 ms for 4-wire, 50 ms for 2-wire, or RTS can be forced on
• Rx data is clamped to mark when no receive carrier detect is present.
• V.23 Modem – FSK Analog Modem, asynchronous

Controls and Indicators

• Power, Tx Data, Rx Data, RTS, CTS, DCD, Test
• Digital loop via rear panel switch and front DIP switch
• Controlled carrier (with RTS/CTS delay) or constant carrier with RTS/CTS on
• Anti-streaming options (8 seconds)
• Loopback or normal operation
• Transmit levels 0 dbm or -16dbm
• 900 Hz Soft Carrier turn off enabled or disabled

Physical and Electrical

• -40C to +75C operating temperature -50C to +75 storage temperature
• 95% non-condensing humidity
• PC ISA bus format or standalone version,
• PC bus for power and ground only, standard standalone unit uses 120V wall mount supply
• Half size PC ISA card, 7.25″D x 4.25″H
• Stand alone: 5.5″ W x 7.375″D x 1.5″ high, 120VAC wall mount supply (9VDC, 500 ma)
• Other DC power supply voltages, 12, 24, -48, 125 VDC, available on special order
• A 1.5″ x 19″ fixture is available to rackmount up to 3 standalones in a single 1U height
• 20 slot rack chassis on slide guides is 19″W x 16″D x 7″H, 110VAC 250 W power supply
• Weight approximately two pounds

Switches

OPTION SWITCH SETTINGS 
Switch                        DOWN                        UP
1 - Reset			OFF			Toggle Up/Down
2 - Anti-streaming		OFF			On        
3 - Phase Equalizer		ON			OFF
4 - RTS Control			Forced ON		RTS Controlled         
5 - Soft Carrier		Turnoff disabled	Enabled   
6 - Line type			4-wire			2-wire
7 - Transmit Level		-16 dBm			0 dBm
8 - Loopback			Loop ON			Loop OFF

APPLICATION