These test procedures are to bring up to date the IRE "Standards on Facsimile-Temporary Test Standards-1943" (43 IRE 9.S1). In part there has been new experience and technological advance since then. But it has also been noted that that document could, to advantage, be made more complete and cover a wider range of tests. An important objective has therefore been to make the new test procedures more comprehensive, to cover tests for determining most of the measurable quantities that were defined in IRE Standards on Facsimile: Definitions of Terms (56 IRE 9.S1, ASA C16.30-1957) now IEEE No. 168. The scope, in part, has been derived from facsimile equipment designed to operate over a telephone frequency bandwidth, but the tests are described in a general way, to make them utilizable over wider bandwidths as far as possible. |