The COM220 phone modem from Campbell Scientific Aust allows users to communicate between data loggers and a computer through a public switched telephone network. With a wide operating temperature range and minimal power requirements, the COM220 phone modem is suitable for use at remote, unattended sites.
A Hayes-compatible modem is required at the base-station computer, while a COM220 connects to the data logger at the field site through the CS/IO ports. Campbell Scientific Aust recommend using surge protects to block incoming electrical transients carried through the phone line.
Features of the COM220 phone modem 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)
- Allows both modem enabled (ME) and synchronous device communications (SDC) modes
- Allows users to set the number of rings before answering a call
The specifications of the COM220 phone modem include:
- Weight: 0.35 lb (0.16 kg)
- Dimensions: 6.5" x 1.0" x 2.6" (16.5 x 2.5 x 6.6 cm)
- Standard operating temperature range: -25° to +50°C
- Extended operating temperature range: -55° to +85°C