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BLACK BOX MD845C-R2 Analog Async Bell 202 Modem, Leased Line, Rack-mount

SKU: 4299 Category:

$719.00

Description

The BLACK BOX MD645C 202T modem is a Frequency Shift Keyed (FSK) modem which is designed for asynchronous operation at 0 to 1800 bps with good line conditioning, or 0 to 1200 bps asynchronous operation on unconditioned lines. The modem provides half duplex communications on 2 wire private lines or full duplex communications on 4 wire private lines, and is ideal for use in multipoint networks.

The 202 modem is a single printed circuit card enclosed in a new compact size housing. The unit features an integral anti-streaming protection option which prevents network Tie-ups by incorporating a delay timer that will disconnect a modem, if it remains in transmit mode longer than a selectable period of time. The 202 modem also features strap options for Request to-Send/Clear to Send Delay timing, Transmit Carrier, local Copy Squelch, Turnaround squelch, Soft Carrier Turn Off, Carrier Detect Level, Carrier Detect Delay, and Test Generator Baud Rate Select. These strap options allow the user greater control of the modem, for his individual application.  

The BLACK BOX MD645C 202T modem features built-in diagnostic and anti-streaming capabilities. The anti-streaming capability prevents a modem from remaining in the transmit mode when the modem is not actively transmitting data. The diagnostic features allow the user to verify transmitted and received data. 

 The  modem is designed to be interchangeable between the Universal Data Shelf multiple modem enclosure (BLACK BOX M421A SERIES) and the stand alone modem enclosure. By removing the modem card and attaching the optional front panel, the modem can be directly inserted into the Universal Data Shelf. With this feature, a data-communications facility can be easily upgrade front multiple standalone enclosures to a centralized rack without the expense and trouble of purchasing new modems. Telenetics had to change some of the older chips for newer analog filters which gives new life to a world class modem. With these new changes we can offer an even a better unit – now with wider voltage choices and a temperature range.

 

Additional information

Weight 5.00 lbs
Dimensions 9.00 × 6.00 × 4.00 in

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  • 2-wire half duplex or 4-wire 202 modem full duplex private line operation
  • 0 to1200 bps data rate over unconditioned lines
    and 1,800 over high quality lines
  • Antistreaming
  • Phase coherent, frequency shift keyed (FSK) modulation
  • V.23 modulation
  • V.24 and RS232 Data Port
  • LED indicators
  • Front panel rotary switch function selector
  • Integral test features
  • Temperature rated -40 to +85° C
  • 12, 24, 48, 125VDC power
  • 115VAC, 60Hz – 220/240VAC 50Hz power

CONTROLS AND INDICATORS

Test Operate Switch

DL (Digital Loopback); When the switch is in the ST position, the received data is looped back into the transmitter and the data is transmitted to the remote end. The modem must be in the 4 wire mode.

TTP (Transmit Test Pattern): When the switch is in the TTP position, the transmitter is forced ON and transmits the date from the dot pattern generator to the COMM Line. The RS-232 interface lines to the transmitter are not active (RS, CS, TD).

DATA: The switch must be in the DATA position for all normal data transmission Indicators

RS (Request to Send): is illuminated when the RS line is high (ON)

CS (Clear to Send): ON when the CS line is high (ON)

CD (Carrier Detect): ON when a carrier is detected by the modem receiver.

RD (Receive Data): On when data is received, decoded, and furnished to the terminal equipment. RD is also ON when the receive cats line goes into a space condition, OFF in a mark condition.

TD (Transmit Data): Responds in the same manner as the RD LED, but only when data to be "transmitted" is furnished to the modem. However, the LED may be on when the DTE is disconnected.

TM (Test mode): Active when Test switch is in any test mode. The indicate' will blink OFF/ON when errors occur in Self Test mode

POWER: ON when power is applied

SPECIFICATIONS

Data Rate: 0 up-to 1,800bps asynchronous 

Operation: Full duplex over 4 wire private lines or half duplex over 2-wire private lines

Modulation: Phase coherent, frequency shift keyed (FSK) and V23

Carrier Frequencies: Mark: 1200 Hz Space: 2200 Hz

Line Impedance: 600 ohms 10% transformer coupled and transient protected

Transmitter Output Level: Selectable from 0, to -12 dbm in 2 dbm steps

Clear to Send Delay: 8.3 ms, 33.2 ms, 59.9 ms, or 219.6 ms (selectable)

Carrier Detect Delay: 6 ms or 23 ms

Digital Interface: EIA RS-232 (DB-25 female) and CCITT V.24

Telco Interface: RJ45 female

Turnaround Squelch: 0 ms, 8.3 ms, or 159.6 ms

Antistreaming: 4, 7.6, 14, 28, 56, none (selectable)

Soft Carrier Turnoff: 0 ms, 8.3 ms, or 26.6 ms

Environmental: -40 to +85° C; 95% humidity, noncondensing          

Mechanical: Width: 7"; Height 2.25"; Depth: 9.60"; Weight  3.0 Lbs.

AC Power Requirement:115 VAC and optional 220/240VAC 50hz, @ 10 watts max

DC Power Requirements: 12 to 60 VDC, optional 125 VDC

BLACK BOX MD645C