Contrails
The goal of the Contrails project is to help preserve and disseminate the technical record of 20th century aerospace research, highlighting in particular the research endeavors of the Illinois Tech community.

Analysis Of Swiss ETK Teletypewriter

Report Number: WADC TR 52-266
Author(s): C. P. Seymor, L. B. Rosenberg
Corporate Author: Wright Air Development Center
Date of Publication: 9/1/1952
Pages: 35
PB Number: PB128602
AD Number: AD0015850
Original AD Number: 15850

Abstract:
An elemental printing technique for error indication in teletypewriter systems was devised by the Dr. Edgar Gretener A. G. of Zurich in which a character consists of a combination of marking bits. Each bit is the result of a finite electrical signal. The machine operated on the asynchronous start-stop principle and utilized a conventional electromechanical printing control system. The character was formed by printing a combination of 14 sign elements, of which a maximum of 5 impressions were required to print any complete character. The rotational torque impressed on the type wheel and another component element was supplied by a 12-v governed motor. A primary power supply of either 110 or 245 vac, or 12 vdc can be used. The equipment may be used with land lines or in conjunction with a radio-telephone circuit, since the output is in the form of an audio tone. The sequence of operation, the functioning of parts, and the operation of a line unit are described in detail.

Contrails does not possess a copy of this report. Click here to offer Contrails a donation of this report

Other options for obtaining this report

Via the Defense Technical Information Center (DTIC):
A record for this report, and possibly a full-image download of the report, exists at DTIC

Via National Technical Information Service:
The NTIS Order Number for this report is: AD015850
This report may have been digitized and made freely available for public download, or made publicly available for purchase by the National Technical Information Service through their online database, the National Technical Reports Library

Indications of Public Availability
A PB Number, PB128602 , exists for this report, indicating public availability of the report at time of publication

No digitial image of an index entry indicating public availability is currently available
There has been no verification of an indication of public availability from an inside cover statement