DESCRIPTION OF MOUNTAIN LAKES TEST STATION 



Fici'ri 2. Viewol Mountain Lakes laboratory from Pier 



61 - 2 Facilities 



system covers the frequency range from 2 c to about 

 100 c. Associated with this system are facilities for 

 varying the temperature and hydrostatic pressure. 



Two intermediate-frequency units, designated sys- 

 tem 1 and system 2, are used with outdoor piers for 

 free field calibration in the lake. Both systems will 

 operate from 15 c to 150 kc and can be arranged to 

 test apparatus with power inputs up to 1,500 watts. 

 The apparatus has been assembled in bays and ar- 

 ranged to provide maximum separation between 

 high- and low-level signal paths to minimize cross 

 talk. This practice of separation has been maintained 

 throughout both systems, including the transmission 

 lines and transducer coupling booths on the piers. 

 Finally, a high-frequency unit which includes an 

 clliplically shaped tank covers the range from 100 kc 

 to 2.2 mc. This unit may also be used in conjunction 

 with one of the piers. 



Other acoustic testing facilities include an open 

 tank with sound-absorbing walls (a type used for pro- 

 duction testing by the Western Electric Company) 



The Mountain Lakes test station provides facilities 

 lor the calibration of underwater acoustic devices 

 from a frequency of 2 cycles per second to 3.5 mega- 

 cycles per second/ 1 This range is covered by means of and a closed cylindrical tank about 15 feet long and 

 four separate testing systems. A low-frequency tank S feet in diameter. The latter can be used at hydro- 

 static pressures up to 300 lb per sq in. and at fre- 



a Transducers available at present will operate up to 2.2 mc. quencies up to about 150 kc. "f'ests at high pressures 



Figure 3. Testing piers at the Mountain Lakes station. 1 he booths housing terminal equipment and the overhead 

 monorail systems are visible. 



