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Smart 64K CSU/DSU, 120-VAC

Get in the loop for quick and complete line analysis.


Limited Quantity In Stock
Typically Ships within One Week
Extended Double Diamond™ Warranty Available (3 Additional Year)

*Required field

Product Features

  • Built-in test-pattern generator quickly tests network faults with BERT functionality.


  • Easy-to-read, front-panel LCD provides "plain English" readouts of line conditions.
  • DDS and sync DTE data rates up to 64 kbps! Async DTE data rates to 57.6 kbps!
  • VDC models can operate at up to 158° F (70° C).
  • Models available for 120 VAC, 24–48 VDC, and 130 HVDC!
  • Error LEDs indicate line impairments.
  • Test and report problems to your service provider in minutes!

    Need comprehensive, comprehensible line analysis? Get a Smart 64K CSU/DSU.

    Error LEDs display line errors as they occur. Then a Digital Signal Processor diagnoses the problems and displays the results on the front-panel LCD, giving you clear, easy-to-understand answers about line attenuation, background noise, impulse noise, bipolar violations, looped conditions, and DDS operating mode. Network optimization, management information, data quality, and seal-current reversal keep your service provider responsive. And a built-in telco line tester enables you to test and report line impairments accurately in just minutes.

    These CSU/DSUs transmit full-packet data over standard DDS lines at async rates up to 57.6 kbps or sync rates up to 64 kbps. Plus, you get real-time statistics on the data port, DDS line, and Frame Relay—and management information on Frame Relay packets as a percentage of utilization.

    You get outstanding performance—even on DDS circuits that may be out of spec!

    Two models are available. The MT190A includes a 120-VAC, 60-Hz external power supply. For applications requiring DC power or tolerance to high temperatures, choose our MT190A-D48. Our 24–48-VDC model is ideal for telcos. Both units can operate in temperatures up to 158° F (70º C).

    When it comes to line analysis, you have to get smart—with our Smart 64K CSU/DSUs.

    These products work with:
    • RS-232 Cable, 25-Conductor, Male/Male (ECM25C)
    • V.35 Interface Cable, Male/Male (EYN450-MM)
    Questions? Contact our FREE Tech Support.

  • Tech Specs

    Connectors Line: (1) 4-wire RJ-48S; Data ports: (1) DB25 F (DCE), (1) M/34 F (DCE)
    DDS Data Rate 2400, 4800, and 9600 bps; 19.2, 56, and 64 kbps
    Diagnostics Operational line testing: In spec/out of spec; Parametric testing (± -0.5 dBm): Line attenuation, background noise, impulse noise
    DTE Data Rate Async: 1200, 2400, 4800, and 9600 bps; 19.2, 38.4, 56, and 57.6 kbps; Sync: 300, 600, 1200, 2400, and 4800 bps; 14.4, 19.2, 28.8, 38.4, 56, and 64 kbps
    Line Type DDS
    Loopback Digital loop, local loop, remote loop, CSU, DSU
    Power MT190A: 120-VAC, 60-Hz, 30-W external transformer; MT190A-D48: 24–48-VDC external transformer
    Protocol Sync or async
    Size 1.8"H x 8.6"W x 8.4"D (4.6 x 21.8 x 21.3 cm)
    Weight 2.6 lb. (1.2 kg)
    This product works with:
    These products work with:
    • RS-232 Cable, 25-Conductor, Male/Male (ECM25C)
    • V.35 Interface Cable, Male/Male (EYN450-MM)
    Questions? Contact our FREE Tech Support.

    * 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.


    Application Diagram


    Double Diamond Warranty

    Extended 1 Year Warranty Available

    Protect your purchase with an additional 1 Year Double Diamond™ warranty!
    Cost: $81.08

    Extended 3 Year Warranty Available

    Protect your purchase with an additional 3 Year Double Diamond™ warranty!
    Cost: $162.15


    Double Diamond™ Warranty (Standard)

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

    The Double Diamond Warranty is our warranty that protects your Black Box® brand products* from accidental damage, including drops, water, and power surges.

    The Smart 64K CSU/DSU 120VAC comes with a standard 1 Year Double Diamond™ Warranty (Standard) already included.

    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.

    * Warranty subject to certain exclusions and limitations ** Certain products may not be eligible.

    What’s more, we also have a 45-day 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.