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Industrial > Modems, CSU/DSUs, Muxes

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38887

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Asynchronous Local RS-232 Multiplexor, 4-Port  

A mux that won't shortchange you for short distances.

38887

Extended Double Diamond™ Warranty Available
(Three years for two)

Product Highlights

  • Time-division multiplexor with an integral short-haul modem.
  • Economical alternative to stat muxes.
  • Four async ports.


    • Description

    Asynchronous Local RS-232 Multiplexor, 4-Port


    Quick Facts

  • Time-division multiplexor with an integral short-haul modem.
  • Economical alternative to stat muxes.
  • Four async ports.

    • Further Details

  • Screw terminal interface on composite port.
  • Support speeds up to 64 kbps per port.
  • Operate at distances up to 3000 feet (914.4 m) over two 24 AWG twisted-pair cables.
  • Plug-and-play installation—no option switches to set.


    • If you’re looking for an economical alternative to leased-line modems and statistical multiplexors, the BLACK BOX® Asynchronous Local RS-232 Multiplexor gives you speed and savings in your async environment!

    Here’s an economical alternative to more expensive stat muxes.

    Our Async Local RS-232 Mux is a time-division multiplexor that supports 4-channel speeds up to 64 kbps. All ports operate at maximum throughput levels with virtually no multiplexing delay. All models have an internal line driver for twisted pair. The units’ internal line drivers provide limited-distance communication over private networks with point-to-point twisted-pair cabling.

    Our Asynchronous Local RS-232 Multiplexor automatically adapts port speeds to the rates of your individual terminals—no clock source is required. Plus, synchronization between multiplexors is maintained automatically.

    NOTE: Must be used in pairs.

    This product works with:
    • CAT5 100-MHz Solid-Conductor Cable, 4-Pair, Straight-Pinned (EYN737MS)
    Questions? Contact our FREE Tech Support.


    Technical Specifications for Asynchronous Local RS-232 Multiplexor, 4-Port:

    Distance (Maximum) — 3000 ft. (914.4 m) on (2) twisted-pair cable (24 AWG)
    Multiplexing Technique — Time division
    Operation — Full-duplex
    Speed (Maximum) — 38887: 64 kbps per port;
    38889: 38.4 kbps per port;
    38891: 19.2 kbps per port
    Protocol — Async
    Interface — Channel: RS-232;
    Composite: 4-wire terminal block
    Connectors — Channel: 38887: (4) RJ-45; 38889: (8) RJ-45; 38891: (16) RJ-45;
    Composite: 4-screw terminal block
    Power — 115-VAC, 60-Hz external power supply
    Size — 38887, 38889: 1.7"H x 7"W x 5.3"D (4.3 x 17.8 x 13.5 cm);
    38891: 2.2"H x 7"W x 5.3"D (5.6 x 17.8 x 13.5 cm)
    NOTE: Must be used in pairs.

    This product works with:
    • CAT5 100-MHz Solid-Conductor Cable, 4-Pair, Straight-Pinned (EYN737MS)
    Questions? Contact our FREE Tech Support.


    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 Asynchronous Local RS-232 Multiplexor, 4-Port:

    Product Data Sheets


    Connect your Asynchronous Local RS-232 Multiplexor, 4-Port with:

    Accessory: EYN556MS-0010

    CAT5e Solid-Conductor Patch Cable, PVC, Straight-Pinned, Beige, 10-ft. (3.0-m)

    CAT5e Solid-Conductor Patch Cable, PVC, Straight-Pinned, Beige, 10-ft. (3.0-m)

    » more info

    Accessory: 523951

    Modular Adapters

    Modular Adapters, DB25 Male/RJ-45 for DTE

    » more info

    Double Diamond Warranty

    Standard Manufacturer's Warranty


    A One year warranty is included.

    Extended Two years for one Warranty Available


    Protect your purchase with an additional Two years for oneDouble Diamond™ warranty!
    Cost: $43.60

    Extended Three years for two Warranty Available


    Protect your purchase with an additional Three years for twoDouble Diamond™ warranty!
    Cost: $87.19

    Diamond

    Double Diamond™ Warranty (Standard)

    Coverage:

    The most complete product warranty exclusively from Black Box

    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 products come with a one- or two-year warranty. Some products, such as copper cables, manual switches, cabinets, and racks, are guaranteed for life! Standard Warranty features are as follows:

    Worry-Free Purchases

    If your new Black Box® brand products are accidentally damaged, you're covered with this no-questions asked warranty. FREE

    Coverage

    Double Diamond™ is the standard warranty that comes with your new Black Box® brand product. Most products come with a one- or two-year warranty.

    Lifetime Guarantees

    Many products, such as copper cables, manual switches, cabinets, and racks, are guaranteed for life.

    Fast Service

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

    Extra Coverage

    Extend your warranty or protect a previously purchased Black Box® brand product* for an additional year for only 10% of the current retail price! And when you do, we give you the second year of extended coverage free! FREE Tech Support Hotline. No cost. No contracts. No kidding!

    No-Risk 45-Day Return Policy

    If it's not right, send it back.
    (Excludes custom built products)

    * 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! Forget It.
    Tech Support Hotline 100% FREE! $$$
    Product SKU Price Quantity
    Asynchronous Local RS-232 Multiplexor, 4-Port 38887 $435.95
     
    Asynchronous Local RS-232 Multiplexors 38889 $469.95
     
    You can find this product in the following subcategory(s)
     

    Add to Cart

    Price: $435.95

    Quantity

    Warranty

    Total

    In Stock

    Shipping Info

    In Stock - orders received before 8PM ET ship same day


    45-day return policy


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