Compatibility Requirements and Considerations of Range Telemetry Tape

Abstract

Range Telemetry Tape crossplay operations may be arranged into four major classes each with unique compatibility considerations: a. Between like recorders at the same Range. b. Between unlike recorders at the same Range. c. Between unlike recorders at different Ranges. d. Between unlike recorders at Range User facilities and the Ranges. Like model recorders at the same Range are more likely compatible and capable of optimum tape crossplay than any other combination. Sometimes this very fact produces an atmosphere of complacency which can invite problems. The assumption that the recorder manufacturer has properly controlled his production for optimum crossplay or for complete conformance to IRIG1 is naive and should not be a substitute for compatibility testing at the using Range facility. With field use and equipment aging, compatibility can be gradually lost without becoming detected. Adjustment procedures at one' site may not be identical to procedures at other sites and perfectly compatible equipments can unknowingly become incompatible. The absence of adequate compatibility testing is the major cause of difficulty with this class of crossplay. Crossplay between unlike model recorders at the same Range poses unique problems but these can be controlled providing the unlike recorders have individually been strictly specified and tested to conform to IRIG Standards. Compatibility testing by the using Range is a definite requirement as manufactures may differ in their interpretation of the IRIG Document or may differ in the extent to which they conform. No manufacturer appears to be knowledgeable regarding crossplay between competitive recorders, and some appear to be just as uncertain about compatibility between complimenting recorders from their own product line. Crossplay between unlike recorders at different Ranges is being accomplished but many factors stand in the way of automatic success for this type of venture. When different equipments, different tape types, different operational procedures, and different procurement specifications all combine, the compatibility of the whole system is strained. The possibility of different tape types specified by competing equipment manufacturers should produce cautious awareness by the user and compatibility testing with both tapes should be conducted. The question "Which Range is responsible for the incompatibility?" can be difficult to answer. Currently, no central agency exercises control over Range-to-Range crossplay compatibility, and each Range conforms to IRIG Standards on an individual basis. Crossplay between unlike reproducers at Range User facilities and Range copy recorders is probably the most severe test of compatibility that exists. In this type of crossplay IRIG Standards may not have been invoked by the Range User, different bandwidth classes of systems may be involved and the fact that the User, and the Range may be virtually strangers all promote an environment unconducive to compatibility. Anything that can possibly go awry usually does. The major responsibility must lie with the Range who supplies the original or copy tapes to the Users. Ideally, the copy tapes should all be generated identically regardless of individual recipient requirements, and the IRIG Standards should be religiously followed.