
    All The Popular High Speed Standards, In One High Performance Modem


       The Courier HST Dual Standard is probably the most versatile, widely
    compatible high speed modem in the world.
       It can communicate at 14,400 bps using V.32bis, or 16,800 bps using
    HST.  With V.42bis data compression, throughput can reach 57,600 bps, or
    picture an archived file transfer at over 2000 CPS!
       And only Couriers have ASL - Adaptive Speed Leveling.  All modems
    slow down for line noise.  Couriers can speed up again when conditions
    improve. The others leave you in "low", which can turn a $1 call into a
    $10 call.
       Only the Courier Dual Standard gives you communication with the vast
    established base of HST and V.32 modems, as well as the V.32bis modems
    that are now entering the market.
       It can handle every popular modulation technique in the world from
    300 to 16,800 bps, synchronous and asynchronous.  It works over dial-up
    lines. And of course, it's compatible with MNP Levels 2-5, V.42, and
    V.42bis.


       In V.32bis mode:


    Under V.32bis, you get true, full duplex, high speed transmission -
    synchronous or asynchronous.  You can communicate at 14,400 bps in both
    directions simultaneously.
       And our Intel 80188 processors can really deliver that speed, even
    if you're using V.42bis data compression in both directions.  With
    slower Z80s and 8031s, you don't get full speed.
       V.32bis mode gives you national and international compatibility with
    a variety of high speed modems, plus the synchronous communication many
    mainframes require.


       In HST mode:


    HST's unique asymmetrical duplex design has a 16,800 bps data channel,
    and a 450 bps back channel. The big data files automatically get the
    high speed channel.
       You have the asynchronous transmission you need for minis, PCs, and
    terminals. And at high speeds, you're compatible with the vast
    installed base of HST modems.


       HIGH SPEED FEATURES AND BENEFITS

    UNDER CCITT PROTOCOLS:

    High speeds: 14.4, 12.0, 9.6, 7.2, and 4.8 Kbps.

    Maximum throughput: 57.6 Kbps. You can save up to 90% on a phone call.

    High speed compatibility: CCITT V.32bis at 14.4, 12.0, 9.6, 7.2, and
    4.8 Kbps. CCITT V.32 at 9.6 and 4.8 Kbps.  Fully compatible with high
    speed international standards.

    Symmetrical full duplex operation means instantaneous screen response,
    and optimal two-way transmission.

    Asynchronous transmission at all speeds for PCs, minis, and terminals.

    Synchronous transmission at speeds above 300 bps for mainframes.

    UNDER THE HST PROTOCOL:

    High speeds: 16.8, 14.4, 12.0, 9.6, 7.2 and 4.8 Kbps with back channels
    at 450 and 300 bps.

    Maximum throughput: 57.6 Kbps. The fastest available on dial-up lines.

    High speed campatibility: HST. You're compatible with the vast
    installed base of HST modems.

    Asynchronous transmission puts you in high speed communication with
    terminals, minis, and PCs.

    Demand-driven direction control automatically switches the high speed
    channel direction if data demand reverses.

    Asymmetrical duplex operation. The 16.8 Kbps data channel and 450 bps
    back channel are highly efficient for one-way file transfers.



    STANDARD ON ALL COURIER HIGH SPEED MODEMS

    Features And Benefits

    COMPATIBILITY:

    CCITT V.22bis at 2400 bps.

    CCITT V.22 and Bell 212A at 1200 bps.

    CCITT V.23 at 600 and 1200 bps.

    CCITT V.21 and Bell 103 at 300 bps.

    You have on-line compatibility with all popular 300 - 2400 bps modems.

    ERROR CONTROL AND DATA COMPRESSION:

    CCITT V.42 error control.

    MNP Levels 2-4 error control.

    CCITT V.42bis data compression.

    MNP Level 5 data compression.

    You get 100% error-free data, and maximum throughput.

    Trellis-coded modulation is twice as effective as QAM in protecting
    your data against phone line noise.

    CONVENIENCE:

    Nonvolatile Random Access Memory. Easily programmable memory keeps
    user-defined configuration.

    Phone number storage gives you an auto-dial directory of four
    frequently used numbers.

    Auto Dial. Using the "AT" command set in asynchronous mode, you can
    dial or program from your keyboard.

    Auto Answer. You don't have to run for the phone or stand by a switch.

    Automatic Redialing will redial up to 10 times, automatically.  Useful
    if you know the modem you're calling is frequently busy.

    ASL (Adaptive Speed Leveling (tm)), up or down, gives you 100% error-
    free transmission at the highest possible speed under prevailing line
    conditions. Automatically selects the highest speed and error control
    protocol supported by the remote unit.  You get the maximum possible
    throughput, and you don't have to worry about compatibility.


    ***On screen help gives you instant answers to most questions without
    opening the manual.

    Externally accessible DIP switches. No disassembly required.

    RS232 pins 2 and 3 (Send and Receive) are switch-reversible.  Easy to
    use with terminal, computer or printer.  (Desktop models only.)

    Flow control allows fixed RS232-C rates up to 57.6 Kbps.  You're not
    confined by a slow port speed.

    12 LED front panel indicators. You can clearly see what your modem is
    doing. Diagnosing a problem is easy.  (None on internal models.)

    Built-in speaker with volume control. You can hear call progress.  (Not
    on rackmount models.)

    Bottom label help summary. Particularly helpful for setting dip
    switches. (Desktop models only.)

    Complete diagnostic capability. Local analog, digital loopback, and
    remote digital loopback self-testing make pinpointing a problem easy.

    U.S./CCITT answer sequences. You're compatible with the current
    standard.

    FOR YOUR INFORMATION

    Warranty: A full 2-year warranty on parts and labor, which you may
    extend indefinitely for a nominal fee.

    Package Contents: Modem, power adapter, RJ11C phone card, manual.

    IBM, IBM PC, IBM PC/XT, IBM PC/AT AND ISM Personal System/2 are
    trademarks of International Business Machines Corp. U.S.  Robotics and
    the USRobotics logo are registered trademarks, and Courier, Courier
    HST, Courier HST Dual Standard, Courier V.32bis, ASL, Total Control,
    and Rackmount 32 are trademarks of U.S.  Robotics, Inc. MNP is a
    registered trademark of Microcom, Inc.  Apple is a registered trademark
    of Apple Computer, Inc. UNIX is a trademark of AT&T Information
    Systems. Intel is a registered trade mark of Intel Corp.
    (c)1990, 1992, U.S. Robotics
















