ESTP ALSEP / MSFN Compatibility and Performance Test Status Review

Abstract

MSFN/ALSEP interface specification documents require MSFN transmitter carrier deviation to be in phase with the polarity of the modulation voltage. Compatibility tests of MSFN and ALSEP performed at MSC, indicate the ALSEP receiver inverts the transmitted command modulation. ALSEP receiver specifications require the detected output to be in phase with the carrier deviation. Tests performed on the MSFN and USBSS test transmitter at MSC show these transmitters produce the required in-phase command modulation. The same test performed on an ALSEP up link test transmitter at Bendix Aerospace Systems Division, Ann Arbor, Michigan shows inversion of the transmitted command modulation. This memo presents a discussion of the test technique and the results of each test.