COM220

Phone Modem

The COM220 modem enables communications between a computer and a Campbell datalogger via a public switched telephone network. A Hayes-compatible modem is required at the base-station computer while a COM220 connects to the datalogger at the field site. The COM220's wide operating temperature range and minimal power requirements make it ideal for use at remote sites. A surge protector to help suppress incoming electrical transients carried down the phone line is strongly recommended.


Features

Improvements over its predecessor, the COM210, include:
  • Supports communication rates up to 115.2 kbps between modem and logger. (In practice, data transmission through phone lines is generally constrained to 33.6 kbps.)
  • Offers both modem enabled (ME) and synchronous device communications (SDC) modes.
  • Allows user to set the number of rings before answering call.

Specifications

  • Standards: V.92, K56Flex, V.90, V.34, V.32bis, V32, V23, V22bis, V22, V.21, B212, B103
  • Registration
    • FCC US: 3A4M508BSM2-T-W
    • IC 2377 A-SM2TW
    • TBR21
  • Operating Voltage: 12 Vdc
  • Current Drain
    • Quiescent: ~12 μA
    • Active: ~30 mA
  • Communication Rate Between Datalogger and COM220 (selected by user): 9600, 38400, 57600, 115200 bps
  • Operation: Full-duplex over standard analog phone lines