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TLB704A

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Buffered 4-Port RS-232 Modem Sharing Device  

Expand leased line, polled environments without adding computer ports or communications links.

TLB704A

Extended Double Diamond™ Warranty Available
(3 Year)

Product Highlights

  • Increases network efficiency.
  • Transparent to data.
  • Fully cascadable.

  • Description

    Buffered 4-Port RS-232 Modem Sharing Device


    Quick Facts

  • Increases network efficiency.
  • Transparent to data.
  • Fully cascadable.

  • Further Details

  • DCE/DTE selectable.
  • Internal or external clocking.

  • The Buffered Modem Sharing Device is a network expansion device for modem sharing or port sharing applications in polled or contention environments. It allows up to four devices to share a modem/DSU or computer port. Any combination of terminals and modems may be used in a network environment.

    Each port may be selected as a DCE or DTE interface. Once installed, system and network efficiency are increased through higher host processor utilization coupled with the significant decrease in idle time between host/terminal traffic sessions.

    Ideal for either synchronous or asynchronous network environments, the Sharing Device is protocol transparent at data rates up to 128 Kbps. It may be configured to provide clocking for the entire network. To prevent data transmission errors caused by clock differentials throughout the network, an 8-bit buffer is provided. In applications where the master port and the selected port provide their own clocks, data is clocked into the buffer at the receive clock rate of the active port and clocked out using the master port transmit clock.

    In applications where the Clear To Send control signal is not provided by the master port, an artificial RTS/CTS is available. Additionally, several RTS/CTS delay settings are available.

    The Buffered Modem Sharing Device provides optional Anti-Streaming circuitry. Once enabled, Anti-Streaming will automatically remove a defective terminal or modem from service if the Data / Control criteria is present for the user predefined selection period.

    Housed in a sturdy metal enclosure and equipped with an internal 110/220VAC switch selectable linear power supply, the DMM-4 will provide in excess of 100,000 hours of reliable service.


    Technical Specifications for Buffered 4-Port RS-232 Modem Sharing Device:

    Interface EIA RS-232, CCITT V.24 using DB-25 female connectors, ±15KV ESD protection
    Terminal Service Modes Sequential scanning for RTS, DCD, or data
    Timing Internal or external
    Indicators Power, Transmit Data, Receive Data, Channel Active, Channel Stream
    Power 100–120 to 200–220VAC @ 10%, 50/60Hz, 0.16/0.08A,
    External 110/220 volt select switch, IEC Power Inlet, (2) 5-mm fuses
    Dimensions 1.75”H x 17”W x 9”D (4.4 x 43.2 x 22.9 cm)
    Weight 4.5 lb. (2.1 kg)

    This product includes:
  • (1) power cord
  • Manual


  • NOTE: Technical specification weight is the unit weight. It is not the packaged shipping weight. For shipping weight, please contact Black Box customer service at 877-877-2269.


    Resources for Buffered 4-Port RS-232 Modem Sharing Device:

    Product Data Sheets


    Connect your Buffered 4-Port RS-232 Modem Sharing Device with:

    Double Diamond Warranty

    Standard Manufacturer's Warranty


    A warranty is included.

    Diamond

    Double Diamond™ Warranty (Standard)

    Coverage:

    Take the risk out of equipment purchases with the Double Diamond™ Warranty from Black Box Network Services.


    The Double Diamond Warranty is our no-questions-asked warranty that protects your Black Box® brand products* from accidental damage, including drops, water, and power surges.

    Most of our products come with a one- or two-year warranty. Some products—such as copper cables, manual switches, cabinets, and racks—are even guaranteed for life!

    During the warranty period, Black Box Network Services will repair or replace your damaged equipment within one week of receipt at NO CHARGE!

    Plus, get an Extended Double Diamond Warranty.


    You can also extend your warranty or protect a previously purchased Black Box® brand product* for an additional year—for only 10% of the purchase price! Or, extend your coverage for a full three years for only 20% of the purchase price!

    Ordering an extended warranty is easy: When viewing a product in your shopping cart, just select the one or three years of additional coverage in the dropdown menu under “Warranty Options.” For details, contact Customer Service at 724-746-5500.

    * Certain products may not be eligible.

    Warranty Compared

    Black Box® Double Diamond™ Warranty The Competition
    Warranty Length One Year to Lifetime, Depending on the Product. Read the fine print.
    Guaranteed for Life! Black Box® Brand Copper Cables, Manual Switches and More! No.
    Accidental Damage 100% Covered! No.
    Water Damage 100% Covered! No.
    Power Surges 100% Covered! No.
    Warranty Replacements No Questions Asked! ?
    Tech Support Hotline 100% FREE! $$$

    What’s more, we also have a 45-day, no-questions-asked return policy. Simply call Customer Service for a Return Authorization (RA) number, return your product in new condition and in the original package, and receive a full refund.

    Product SKU Price Quantity
    4-Port RS-232 Modem Sharing Device TL704A $595.95
     
    8-Port RS-232 Modem Sharing Device TL708A $795.95
     
    Multiport Modem Sharing Device, 2-Port 33821 $368.95
     
    You can find this product in the following subcategory(s)
     

    Add to Cart

    Price: $695.95

    Quantity Available: 5

    Quantity

    Warranty

    Total

    Shipping Info

    In Stock - orders received before 5PM ET ship same day

    Weight: 5.814 lbs.
    HxWxD: 0 x 0 x 0 in.

    What’s more, we also have a 45-day, no-questions-asked return policy. Simply call Customer Service for a Return Authorization (RA) number, return your product in new condition and in the original package, and receive a full refund.


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