HomeAbout ZoomTechnical SupportPartnersWhere To BuyProductsContact UsSearch  
ZOOM Products

ZOOM® ComStar™ 28.8 Speakerphone/Voice FaxModem
A Complete Communications Center For Your Computer!©

ComStar 28.8 (Model 620) is a complete communications center for IBM® PC-compatible and Macintosh® computers. The ComStar combines a full-featured 28,800 bps V.34 faxmodem with 14,400 bps fax, full-duplex speakerphone, digital answering machine, voice mail system, and a convenient speed dialer.

The ComStar is an easy-to-install, single-slot card. It is software-configurable and "Plug and Play" compatible with Windows® 95. ComStar comes complete with a high-quality microphone and speaker, and all necessary software.

ComStar 28.8 is built in the U.S.A. by Zoom Telephonics, Inc., a leading supplier of telecommunications equipment since 1977.


  • Speakerphone: Get the convenience of hands-free, full-duplex telephone conversations and professsional quality conference calls. Complete with high-quality microphone and speaker.
  • Data Modem: Connects at 28,800 bps with V.34, the fastest international standard - perfect for connecting to the Internet, remote access to other corporate locations, bulletin boards, and on-line services. Features V.42bis, V.42, MNP® 2-5, and advanced MNP 10ECTM for fast, error-free file transfers.
  • 14.4 Fax: Send and receive great-looking high-resolution faxes at your PC, plus faxback and fax-on-demand. Improve your productivity and present a more professional image.
  • Plug and Play: Automatic configuration with Windows 95 on Plug and Play compatible computers. Software configuration too. No jumpers to set!
  • Voice Mail and Digital Answering Machine: A powerful and easy-to-use multi-mailbox answering system for a professional image at home or at the office.
  • Speed Dialer: Fast and easy "point-and-click" directory dialer.
  • Distinctive Ring: Share voice, fax, and data communications on a single phone line (requires local telephone company support).


Data speeds and protocols
  • V.34 - 28,800/26,400/24,000/21,600/19,200/16,800/14,400 bps data
  • V.Fast Class - 28,800/26,400/24,000/21,600/19,200/16,800/14,400 bps data
  • V.32bis - 14,400/12,000/9600/7200/4800 bps data
  • V.32 - 9600/4800 bps data
  • V.22bis - 2400/1200 bps data
  • Bell 212A, V.22A/B, V.23 - 1200/600 bps data
  • Bell 103, V.21 - 300 bps data
Send/receive fax speeds and
  • Group 3, Class 1 and 2 fax
  • V.33, V.17 - 14,400/12,000
  • V.29, V.17 - 9600/7200
  • V.27 ter - 4800/2400
  • V.21 channel 2 - 1200/300
Command set: Hayes AT-Command compatible, with extended MNP®5, MNP 10, and V.42bis commands
Error correction: V.42-LAPM and MNP 2-4; MNP 10 data throughput enhancement; MNP 10EC Enhanced Cellular
Data compression: MNP 5, V.42bis
Voice encoding: Enhanced ADPCM, programmable at 2 or 4 bits per sample
Business audio mode: Monophonic record/playback using 8-bit encoding at 11.025 kHz or 7200 Hz
Speakerphone: Full-duplex with microphone and speaker included; headset capability
Interface: Plug and Play; IRQ 3-5, 7; supports TAPI
Hardware Features
  • Dual RJ-11 telephone jacks- one for phone line, one for optional phone
  • Software volume control
  • Output jack for external 8 ohm audio speaker (8 ohm external speaker included)
  • Input jack for external microphone (microphone included)
  • Jumper-selectable electret microphone bias
  • Telephone cable with RJ-11 connectors
  • Buffered 16550 UART to reduce PC interrupts and boot performance
  • Handset record and playback
Dimensions and Power Requirements
  • Standard IBM PC-compatible board (8-bit ISA)
  • Power consumption: 3.8W max; 1.1W idle
System Requirements
  • 486 or faster PC compatible computer with 1 available 16-bit ISA slot
  • 8 MB RAM
  • 3.5 in. floppy drive
  • Hard drive with 5 MB available
  • Microsoft Windows 3.1 or higher
  • Mouse recommended
Certifications and Warranty
  • FCC Registered (Part 68) and Certified (Part 15B)
  • Recognized to U.S. and Canadian requirements under the Component Recognition Program of Underwriters Laboratories, Inc.

Zoom Telephonics, Inc.
207 South Street
Boston, MA 02111
Fax: 617-423-3923
Web Site: www.zoomtel.com
NASDAQ: ZOOM Zoom is a registered trademark, and ComStar and Zoom/FaxModem are trademarks of Zoom Telephonics, Inc. Microsoft and Windows are registered trademarks of Microsoft Corporation. MNP is a registered trademark and MNP 10EC is a trademark of Microcom.

Made in the U.S.A.
©2000 Zoom Telephonics, Inc.

©2003 Zoom    Home | About Zoom | Technical Support | Partners | Where to Buy | Products | Contact Us | Search