terminal end. If so, then the common miode frequency will be 60 

 c.p. s. and the CMR necessary will be the greatest that is practi- 

 cally possible to obtain. 



MR. ROBERT M. SPIEGEL (Polorad Electronics): 1. Cannot 

 Omega's 8-mile ambiguity be resolved by audio modulation of the 

 carrier? Z. What firms are developing equipment? 3. Cannot the 

 problem of large distance from shore for fixed stations fornning 

 part of navigational systems be overcome by permanently anchor- 

 ing buoys or "electronic lighthouse" vessels for navigational refer- 

 ence purposes? 



LIEUTENANT COMMANDER R. P. DINSxMORE ( USCG): 1. In the 

 Omega program a ZOO-cycle FSK modulation originally was includ- 

 ed to resolve the 8-mile ambiguity. This is a complex circuit, 

 however, and was dropped about two years ago on the basis that 

 its complexity outweighs its usefulness. 2. Commercial firms 

 presently developing Omiega receivers are Motorola and I. T. & T. 

 The Naval Research Laboratory also is conducting developmental 

 research. 3. The large power requirements (30 kw, ) and elabo- 

 rate antenna array obviates the use of buoys in a Loran or other 

 similar chain. Further, Loran is only semi-automatic and re- 

 quires constant manual monitoring and synchronization. The use 

 of an anchored ship is possible although antennas, maintenance, 

 and positional requirements make such consideration marginal. 

 Coast Guard experience with lightships indicates a station keep- 

 ing error which would be greater than the accuracy of a high 

 performance system. A moored shipboard transmitter whose 

 position is automatically determined and synchronized to two 

 other stations in a chain is feasible but has not been considered 

 to date. 



MR.- R. E. TRIPPENSEE (Wildlife Supply Company): Are re- 

 search pressure tanks available -- small size -- where -- price? 



MR. J. M. SNODGRASS (SIO): Yes. The smallest size that I am 

 aware of is rated nominally at 100 ml. The dimensions of the 

 small chamber are 1-1/4 in. (inside diameter) by 5 in. (inside 

 length). This particular one may be obtained in two pressure 

 ranges, one 12, OOOp.s.i. at a nominal 650 F. maximum, or 

 30, 000 p. s.i. at 650° F. maximum. They are available all the 

 way up to what may be called plant- size reactors, which are, 

 for instance, 12 ft. inside depth by 12 in. inside diameter. I 



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