Bird Technologies ACMI - Manual (Page 38)

26
Push-to-Talk
When enabled, the Push-to-Talk (PTT) feature monitors the PTT logic input on
the DB-15 connector. When the PPT input is not asserted (low or open), the low-
power and VSWR alarms will not be monitored. When the PTT logic input is
asserted (i.e. when the transmitter is keyed) the PTT delay timer will begin to
countdown. During this PTT Delay, the low-power and VSWR alarms will con-
tinue not to be monitored. The alarms will be monitored only when the end of
the PPT Delay is reached and the PTT logic input is still asserted. This prevents
false alarms while monitoring for low power and high VSWR.
Note:
The VSWR Alarm Enable and/or Low Power Alarm Enable
must be enabled (checked) in order for these alarms to activate after a
PTT logic event and delay.
Setting Push-to-Talk
1. Open the Power Monitor Options dialog.
2. Do one of the following:

Check the Enable checkbox to turn the Push-to-Talk feature on.

Uncheck the Enable checkbox to turn the Push-to-Talk feature off.
3. Enter any value for the time up to 14 sec.
Note: The time actually programmed on the ACM will be a multiple
of 156.25 ms. For this reason, the time displayed will be slightly differ-
ent from the time set. The actual delay from the PTT signal is uncertain
because the PTT signal is asynchronous to the internal measurement
samples. The uncertainty is +/- 156.25 ms.
Figure 18 Push-to-Talk