AEROGRAPHER'S MATE 3 & 2 



209.434 



Figure 7-1. — Model 40 Keyboard Visual Display Terminal (KVDT). 



the COM EDS weather circuits. This teletype- 

 writer, identified as a KVDT, consists of a 

 keyboard, display, and a printer. The keyboard 

 is similar to the keyboard of a typewriter. 

 The display is a cathode ray tube which dis- 

 plays the characters typed on the keyboard. 

 Special controls permit the operator to change 

 the data displayed. The printer is a 1200 word 

 per minute teletypewriter which prints only 

 incoming data. 



Model 28 R/O 



The Model 28 R/O teletypewriter (fig. 7-2) 

 is used for receiving weather data only. It does 

 not normally have a keyboard. The only control 

 keys provided on this machine besides the power 

 switch are the carriage return (CR) key, which 

 provides a means of locally returning the type 



box to the left-hand margin, and the line feed 

 (LF) key, which provides a means of locally 

 feeding up the paper. 



SHIPBOARD TYPES 



Most of the teletypewriter sets used by 

 Navy ships belong to the model 28 family of 

 teletypewriter equipments. The model 28 equip- 

 ments feature light weight, small size, quiet- 

 ness, and high-speed operation. They present 

 relatively few maintenance problems, and are 

 suited particularly for shipboard use under severe 

 conditions of roll, vibration, and shock. 



Another feature of the model 28 teletype- 

 writers is their ability to operate at speeds 

 of 60, 75, and 100 words per minute. Con- 

 version from one speed to another is accomplished 



124 



