microHAM © 2010 All rights reserved
PTT & 2
nd
PTT PORTS
The PTT channels are used to control transmit/receive switching of the transceiver and power amplifier. An
internal sequencer assures 100% protection against hot switching of the PA when the PTT channel is used.
More information about T/R switching and the sequencer is provided under the PTT tab.
Router allows assigning virtual serial ports for PTT using the DTR or RTS signals. DTR* and RTS* are
identical to DTR/RTS except that the output is inhibited for one second after the COM port is opened and .
should only be used with programs that cause unwanted key-ups during startup.
TIP: More applications use RTS for PTT than DTR.
The state of the PTT channel is indicated by a green
arrow. If the port is opened, it does not mean it is
properly configured. When the port is properly
configured, the arrow will light during the entire
transmission. To test PTT operation, click on the Test button with no port assigned or the port closed.
The 2
nd
PTT channel is identical to the primary PTT channel. 2
nd
PTT provides a way for a second
application to key the radio if the primary application also controls PTT – for example, a logging program
and CW reader/keyboard.
To test PTT, click on the Test button with no port assigned or the port closed.
NOTE: The test buttons do not activate PTT in voice modes.
FOOT SWITCH
Even though many applications do not monitor the status of the foot switch and do not have the ability to
perform specific functions base on closing or releasing the foot switch, we have decided to implement this
feature in Router. Hopefully sometime soon applications will be able to detect the foot switch status and use
this this information for automating user functions like in the DOS based TRLog.
Router allows assigning a virtual serial port to the foot switch channel and selecting one of four available
input control lines (CTS, DCD, DSR or RING).
NOTE: CTS is not available if the foot switch channel is shared with the radio control port. The state
of the signal on the virtual port can be inverted by checking inverted box.
When a COM port is assigned for the foot switch but the application does not support foot switch status (or
no application is running), Router reports the channel as closed.
When an application opens the COM port (usually
at start-up), Router reports channel as open.
When the foot switch is pressed, this state is indicated by a red arrow.
26
