microHAM © 2010 All rights reserved
CW PORT
By its very nature, USB is not well suited to transfer the real time events required for CW keying. In
addition to the latency inherent in the USB protocol, delays due to CPU load, internal Windows message
processing (inter-process communication) and data flow from another peripherals sharing same the USB
root hub can result in transmitted characters that are garbled. To minimize these unwanted operating
system effects Router uses a specially developed oversampling and prediction algorithm to assure the
smoothest possible transfer of control signal events over USB. Using these techniques, CW keying in the
Router is, in most cases, usable up to 50 WPM if the application generates keying signals accurately and
does not consume 100% of CPU time at the highest priority class.
Router allows assigning a virtual serial port for software CW using DTR or RTS signals. The DTR* and
RTS* are identical to DTR/RTS except that the output is inhibited for one second after the COM port is
opened. RTS*/DTR* should only be used with programs that cause unwanted key-ups during startup.
TIP: More applications use DTR for CW than RTS.
When an application opens the COM port (usually at
start-up), Router will indicate the channel is open.
The state of the CW channel is indicated by a red arrow. If port is opened, it does not mean that it is
properly configured. The red arrow will light in time with the transmitted CW when the port is properly
configured.
To test CW operation, click on the Test button with no port assigned or the port closed.
PTT & 2
nd
PTT PORTS
The PTT channel is used for T/R switching of the transceiver, Power Amplifier and Low Noise Preamplifier
(LNA). An internal T/R sequencer assures 100% protection against transmitting through the LNA or hot
switching of the PA when the PTT channel is used for T/R switching. More information about T/R switching,
DIGI KEYER II PTT outputs and the sequencer is provided under the Keying Tab (page 21).
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.
TIP: Always use serial PTT instead of the radio command PTT or VOX. It is the only way to assure
proper sequencing of a Power Amplifier, LNA, or receive antenna switch.
To test PTT, click on the Test button with no port assigned or the port closed.
23
