TIMTER™ Multi-mode Digital Telemetry Transmitter
72
Quasonix, Inc.
XDC 1 Set the TTL control output to 0 (assume polarity invert is set to 0)
XDC 0 Set the TTL control output to 1 (assume polarity invert is set to 0)
4.2.1.1.19 External Device Channel Command
– XDCH
The XDCH command allows the user to select the current control output “channels” used by the XDC, XDF, and
XDP commands. The “channels” refer to pin 3 and pin 8 on the MDM-9 connector, as shown in the pinout table in
the XDC section (4.2.1.1.18). Pin 3 is the Channel 1 external device control output, and pin 8 is the Channel 2
external device control output.
The XDCH command sets the “channel” to 1, 2, or 3 for both. If “channel” 1 or 2 is selected, only that “channel”
changes. If “channel” 3 is selected, both settings change together.
(This command is similar to the CH command used on a Dual Transmitter.)
4.2.1.1.20 External Device Frequency Switching Threshold Command
– XDF
The XDF command sets the frequency threshold at which the TTL control output changes states. This command has
no effect unless XDC is set to Auto.
XDF accepts and displays up to six decimal places, meaning the frequency (in MHz) can have precision down to 1
Hz. The trip point may be set to any frequency the transmitter supports. The valid range is 200.0 MHz to 5260.0
MHz.
Syntax:
XDF
[
?/freq
]
where freq is the frequency at which the TTL control output changes states if XDC is set to auto.
Which state it changes to depends on the setting of XDP:
if FR >= XDF then output is 1 if XDP is 0 (no invert)
or 0 if XDP is 1 (invert)
if FR < XDF then output is 0 if XDP is 0 (no invert)
or 1 if XDP is 1 (invert)
Examples:
XDF ?
Help
XDF
Show the current external device frequency switching threshold
XDF 4430.0
Set the current external device frequency switching threshold to 4430.0 MHz
