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Modem Sharing Device

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Modem Sharing Device


Make someone happy - share a modem ! At a price that will make YOU happy !

Introducing a modem sharing device so easy to use that the two users may forget they are sharing a modem. Sharing an expensive resource like a modem and a phone line is more productive and saves money when simultaneous use is not required.

There are no switches to flip, no knobs to turn. This tiny device is automatic. It draws its ultra-low power from interface signals, so it does not require any AC power or batteries. And it is small enough to plug direct into your modem.

Terminals contend for modem by raising RTS. The MSD senses RTS and automatically "connects" that terminal. After that, the other terminal is blocked from connecting until the first terminal drops RTS. It operates with async or sync terminals, passing on external clock signals from modem to terminals.

Unlike :modem splitters" where two terminal inputs are OR-tied, this MSD actually swithces the connection. This means that while one terminal is "connected" another terminal cannot disturb the operation even if it raises its RTS or sends data.

For flexibility in handling data going from modem to terminals, this MSD is available in two versions. In both versions, data from a terminal reaches the modem only if that terminal has raised its RTS and won the connection. But the Polling version broadcasts the data from modem to both terminals. The Non-polling version does not broadcast. It actually switches the data path. Data from a modem will reach a terminal only if that terminal has raised RTS and won the contention.

Shares a modem between two users
Contention by RTS
Data rates to 38400 bps
Polling or Non-polling
Sync or async
No AC power or batteries
Transparent of data format
Excellent value for money


2412 - P
Modem Sharing Device, Polling Version
2412 - N
Modem Sharing Device, Non-polling Version
Data Interface
RS-232/V24 DCE
Upto 38400 bps
Contention RTS
Modem Interface RS-232/V24 DTE
Power None required
64 X 53 X 15 mm
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