Specifications
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Unfortunately, many radios fail to provide a separate mode for digital operation or the  
control protocol implemented in the radio does not report the digital mode when operating  
AFSK, PSK and other audio based digital modes. This is true for all Kenwood transceivers 
as well as many Icom and Ten-Tec radios. In those cases, digital operation must done  
using voice modes (USB, LSB or FM). 
The traditional method – feed the microphone jack with sound card through a transformer –  
is not optimum for many reasons including the need to turn off the compressor, EDSP and 
other signal processing for digital operation. In addition, the radio's microphone amplifier  
can cause distortion because it is optimized for speech and very often does not have the 
flat frequency response required for digital modulation.
The proper method is to feed sound card audio to the microphone jack only for voice modes 
(SSB, AM, FM) and to the jack designed for digital modes - generally on the transceiver's 
rear panel – when using sound card based digital modes.  
Even though DIGITAL or VOICE mode information may not be available, Router can make an intelligent 
decision about the mode based on operating frequency and apply the appropriate DIGITAL or VOICE 
settings.  When Router detects USB, LSB, AM or FM, the setting of the VOICE/DIGITAL combo box will 
control whether the Digital or Voice configuration will be used: 
Always VOICE: VOICE settings will be used regardless of frequency.
Always DIGITAL: DIGITAL settings will be used regardless of frequency.
According to Digital Band Map: Router will automatically select DIGITAL settings when detecting a 
frequency inside the "Digital Mode" boundaries.  These boundaries can be fully customized in the Band 
Map by clicking: Router | Options | Digital Band Map.
Disable router queries – When this box checked, Router will not poll the radio for operating frequency 
and mode information when that data is not available from monitoring the communication between the 
control software and radio. 
At the bottom of the Radio window is a serial communication monitor. This can be used by experienced 
users who know how to read protocol commands.  The monitor uses colors and signs to indicate which 
device is responsible for the data. Black queries (H-TX) and gray radio responses (H-RX) are from the 
"host" application (e.g., logging software), green packets (R-TX and R-RX) are polls/responses from/to 
Router and not routed to the virtual serial port. 
Router monitors the communication when the host application performs control and polls the radio 
periodically for any missing information (VFO frequencies and mode). Because some applications do not 
poll the radio periodically or completely, Router must enter to this communication to update its internal 
state. In order to avoid confusing the application, when Router polls the radio, data from the application is 
buffered and sent to the radio after Router receives a response to its latest query.  If Router does not 
receive response to a poll within the allowed time or does not understand the response, it displays  "oldest 
query discarded" but all data is sent to the virtual serial port to avoid confusing the application. 
Since USB transmits data in frames with a delay between frames, Router indicates frame boundaries with 
three dots (...). When a packet ends with three dots it means the data continues in the next frame. 
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