Teletype

Q. Now, isn t it true, Mr. Mann, that you had a direct teletype system established between Leverkusen and I.G. Auschwitz ... 

A. I have no knowledge of that. I do recall that Dr. Ambros had asked me and my commercial colleagues once whether we couldn t help him to get a few emplpyees for the offices of the I.G. plant at Auschwitz. And as far as this teletype system is concerned, maybe I can supplement my answer by saying that the system had existed for a long time. It was just a network of teletype lines in which the I.G. plant at Auschwitz probably became included also. 

One chilling teletype from the Vermittlungsteile Wehrmacht had been recovered. Dated three days before war broke out, the message alerted all the Farben plants that the V.W. could be reached by telephone and teletype on a 24-hour basis. Teletype was preferred "because of security and speed in the transmission of news."... 

In contrast to these interactive searches, which are of little appeal to those with large numbers of searches to carry out, there are available two batch-type searches which accept the complete spectrum of the unknown and examine all spectra in the file sequentially to find the best fits. These are the Biemann and PBM search algorithms. Spectra can be entered from a teletype, but in a more common arrangement, a user s data system can be connected to the network for this purpose and the unknown spectra can be down-loaded into the network computer for use in the search, which can be carried out at once, or, if preferred, overnight at 30% of the cost. 

Teletype. The Teletype is an ASR-33, with a printing speed of 10 characters per second. All user communication, including output, in the basic system is implemented through the Teletype. 

Figure 5 shows the communication necessary for manually initiating a calculation to reprocess an old data tape. This situation could arise if, for example, the operator decided to try new limits for the calculation. The user has entered the calculation routine by entering CALL (ESC) at the Teletype. The system responds with questions about the source of the data and calculation parameters to be used. The calculation will begin when the user places the data tape in the paper tape reader. 

Figure 1. Block diagram of single-photon time-correlation apparatus from Barker and Weston 11 HV, high-voltage supplies L, lamp PI, photomultiplier M, monochromator FURN, furnace C, sample cell LP, light pipe F, interference filter P2, photomultiplier AMP, amplifier DISCI, discriminator D1SC2, discriminator T-S, timer scaler DL, delay line TAC, time-to-amplitude converter BA, biased amplifier MCPHA, multichannel pulse-height analyzer TTY, teletype printer and paper-tape punch REC, strip-chart recorder.

After the experiment the raw data can be inspected on the oscilloscope, manipulated and finally recorded on a flat bed recorder for further use. A teletype output of all the spectral parameters provides an excellent record for later reference 17). 

The desk top computer network is shown in Figure 1. The liquid scintillation counters which we routinely use to generate metabolism data include two Beckman LS-200 series liquid scintillation counters and two Tracor Mark III liquid scintillation counters, however, other LSC makes and models may be interfaced. The Tracor counters are equipped with two standard communications output connectors. One is used to drive the printer, the other is available to the user. The Beckman counters use a unique teletype driver but an interface produced by William Palmer Industries can split the signal and provide a standard communication output. Therefore, all data output from the liquid scintillation counters are available in an electrical standard format, RS-232C. Hardware interfacing was therefore simplified and data collection was a matter of software development. 

There are two primary definitions for the term Network. One definition for a network describes a few computers with lots of terminals. Such installations frequently have grown from a batch environment with a large central mainframe computer to which terminals have been added. The term data communications is used to describe terminal (or terminal like) communications between the terminal and host. This is perhaps the most mature communications area. It was developed initially to support Teletype Equipment over telephone lines. 

The generation of frequency sweeps under computer control, described in Section II, 3 (p. 13) is one small aspect of a general tendency towards control of analytical instrumentation by means of digital computers, through appropriate interfacing devices. Several commercial and individually built systems have appeared in which all of the instrumental parameters for frequency sweeps or pulse-excitation (see Section IV, p. 45) are selected by teletype or numerical keyboard input to the computer, which then acquires the spectral data automatically and performs any further processing required. Automatic analysis of spectral peak positions and areas by a computer, and printing of the numerical results on a teletype or... 

A value of 5.2A for the ion-size parameter a yielded straight-line plots of E0 vs. m at each temperature and solvent composition. The intercepts were obtained by standard linear regression techniques. A graphical representation of the data for each of the H20/NMA solvent mixtures at 25°C is shown in Figure 1. The calculations were performed with the aid of a PDP-11 computer with a teletype output. The intercepts (E°) and the standard deviations of the intercepts are summarized in Table III. 

The computer program (TGPL78) is written to extract the copper, tin, and lead values for individual objects from a data file, to normalize the values, and to plot them on a modified teletype terminal. Details of the program can be seen in the Appendixes I-V. Various plotting parameters, such as the computation and plotting of centroids, partitioning of symbols, normalization procedure, and labeling of individual points can be adjusted by the operator. 

The computer program for drawing these plots is tied to a modified teletype ASR 33 which has had Selsyn motors and electronics attached to turn it into a point plotter. The unit was sold by the Typagraph Corp. and is their model T-3. This works in a time-sharing mode with a commercial time-sharing computer company (Dialcom, Inc., Silver Spring, MD.). 

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