Anderson Jacobson AD 342
| Anderson Jacobson AD 342 | |
|---|---|
| Manufacturer | Anderson Jacobson |
| Model | AD 342 |
| Lifetime | |
| Introduced | May, 1975 |
| Communication | |
| Interfaces |
RS-232-C, 20 mA current loop |
| Baud Rates | 110, 300 |
The AD 342 was an acoustic data access coupler manufactured by Anderson Jacobson. It was described as an origin/answer acoustic coupler and supported both originate and answer operation over the public switched telephone network. [1]
An operating manual dated 1974 identifies the device as the "AD342 Origin/Answer Acoustic Data Access Coupler" and documents its installation, controls, and interfaces.[2]
The AD 342 was advertised in the July 23, 1975 issue of Computerworld, where it was depicted and identified by model number. [3]
Description
According to the 1974 operating manual, the AD 342 was an acoustic coupler designed to interface data terminal equipment to a standard telephone handset. It supported originate, answer, and local test modes, and provided both EIA (RS-232-C compatible) and 20 mA current loop interfaces for connection to data terminal equipment. The unit included front-panel controls for power and mode selection, together with status indicators including carrier detect. Acoustic coupling was accomplished using handset cups, and the manual also documents provision for operation with a direct-connect Data Access Arrangement (DAA). The AD 342 operated at data rates of 110 and 300 bits per second, consistent with Bell 103 signaling practice.[2]
History
The AD 342 was publicly introduced in May 1975 as part of a group of six new Anderson Jacobson devices.[1]
References
- ↑ 1.0 1.1 Six AJ Devices make Debut, Computerworld, May 14, 1975, pg. 54
- ↑ 2.0 2.1 "A242 AD342 Acoustic Couplers Operating Manual". Anderson Jacobson. 1974. https://bitsavers.org/communications/andersonJacobson/A242_AD342_Acoustic_Couplers_Operating_Manual_1974.pdf. Retrieved 28 February 2026.
- ↑ Anderson Jacobson advertisement, Computerworld, July 23, 1975, pg. 19
