Specifications

Field Compatibility SDM-650B Satellite Modem
C–2 Rev. 6
C.2 SDM-650B Fairchild-Compatible Modem
To change the standard modem to a Fairchild-compatible modem, the following changes
must be made:
M&C Software U9 FW/0714-6X
Modulator Card AS/0773-3 (Resistor Pack Changes)
Demodulator Daughter Card AS/0929-3 — Variable Rate
AS/0698-X FDC COMP — Fixed Rate
Decoder Software U8 FW/0562-2
C.3 SDM-650B Aydin Data Rate Modem
To change the Fairchild-compatible modem to an Aydin compatible data rate, additional
changes must be made to the Fairchild-compatible configuration:
Modulator Card AS/0773 12 (Aydin Data Rate, crystal = 4.117333 MHz)
Decoder Card AS/0365 4 (Aydin Data Rate, crystal = 4.117333 MHz)
C.4 SDM-650B Comstream Modem
To change the modem to a Comstream-compatible modem, the following changes must
be made:
M&C Software U9 FW/0714-9X
Decoder Card Software U8 FW/0562-3X
Interface Board AS/0627-2
V.35 Interface with Engineering Waiver #212 Modifies
Carrier ON/OFF Control Using RTS (RS)