Comtech EF Data SDM-650B - Manual (Page 116)

Operation SDM-650B Satellite Modem
4–14 Rev. 5
BUF_clk Programs the plesiochronous buffer output clock for:
• External
• Satellite
• Internal
• Ext_Ref
External Mode:
When this mode is selected and no clock is present at the rear of
the modem, the clock will fallback to the satellite clock. The
Satellite mode sets the output buffer clock to the satellite clock,
which is also the fallback clock.
Satellite Mode:
When selected, the doppler shift caused by the satellite will not be
removed.
Internal Mode:
This mode sets the buffer clock to operate from the modem internal
clock.
Ext_Ref Mode:
When this mode is selected and a clock is not present, a fault will
occur. The output buffer clock will not fall back to the satellite clock.
BUF_CNTR This configuration function is used to center the buffer.
Press [ENTER] twice to center the plesiochronous buffer.
BUF_SIZE This configuration function is used to set the size of the buffer.
On entry, the current buffer length is displayed. Use [
↑ ] and [ ↓ ] to select
the desired buffer size. The size will be displayed in bits or milliseconds.
Use the Utility menu to select bits or milliseconds. The buffer size
ranges from 32 to 262144 bits, in steps of 16 bits, or 6 to 96 ms, in
steps of 1 ms.
Press [ENTER] to execute the change.