U.S. Robotics Modem

This was one of the first modems aimed at the home computer market. In addition to the acoustic coupled USR-310 there was a hard wired USR-320 and USR-330. The USR-330 was originate and answer. These brochures are from early 1978.

In those days you had to beg your telephone company to provide a Data Access Arrangement (DAA) so you could hook something directly to the phone lines. It could take weeks to get one installed and they charged about $5 month.

U.S. Robotics Price List, February 1978 (PDF 1.3 MB)

First Advertisement in April 1978 BYTE magazine. (JPG 276K)

The brochures were published without a copyright notice and are in the public domain. (Details)

	0-300 Baud Data Rate Stand Alone Unit Interface: RS232C Half/Full Duplex Acoustic Connection Via Standard Telephone $139 Front of USR-310 Brochure (JPG 60K) Back of USR-310 Brochure (JPG 46K) USR-310 Brochure (PDF 660K)
	0-300 Baud Data Rate Stand Alone Unit Interface: RS232C / 20mA Current Loop Half/Full Duplex Hardwire Connection Via CBS-1001F DAA $299 (Direct Connect) $160 (DAA Style) USR-320 Brochure (PDF 720K)
	0-300 Baud Data Rate Stand Alone Unit Interface: RS232C / 20mA Current Loop Half/Full Duplex Hardwire Connection Via CBS-1001F DAA $324 (Direct Connect) $185 (DAA Style) Front of USR-330 Brochure (JPG 62K) Back of USR-330 Brochure (JPG 60K) USR-330 Brochure (PDF 770K)

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This page was last edited August 14, 2013