possible to reduce size, weight, and heat generation. 



d. It should be versatile enough to record information from a 

 large variety of sensors and transducers, in both digital and analog 

 form, and to include such key information as time, position, course, 

 speed, ship, and cruise number on all data records. 



e. It should employ modular construction, plugboard system pro- 

 gramming, and stored program system control. 



f. It should incorporate, but not be limited to, the following 

 major components to achieve the above: 



(1) A miultichannel, high quality, analog magnetic tape re- 

 corder, having nnodular read-write electronics for direct and FM 

 recording. 



(2) Input commutators: 



(a) A 100 channel simple sequential commutator having a 

 variable sampling rate up to 100 samples per second. This commuta- 

 tor also should have a switching miode wherein sequential groups of 



10 channels can be selected. 



(b) A multichannel simiultaneous sample hold and multi- 

 plex commutator having a variable sampling rate up to 12,000 per 

 second. 



(c) A commutator control unit to permit combined or in- 

 dependent use of the two commutators. 



(3) Analog to digital converters: 



(a) A 12 bit bipolar A-D converter having a variable sam- 

 pling rate up to 12,000 samples per second. (Small aperture, 50 

 microsecs. ) 



(b) A 12 bit bipolar voltage to frequency type A-D con- 

 verter having a variable sampling period in the range of 10 msec, 

 to 1 sec. 



(4) A small scale digital computer having the following char- 

 acteristics: (1) 12 microsecond add time, (2) 4,096 words of random 



396 



