VarAC and Alinco DX-SR8. – Gereons Homepage

So I tried to use the Alinco DX-SR8 with VarAC – it didn’t work at all. No frequency change, no frequency read out. PTT via CAT does not work on the TRX anyway, as you can read here (see „Firmware Bug“).

But also using the DTR option did not work. When I tried, I got an error message „Null reference“ (or so, It got it in German…).

So I monitored the serial port with a serial monitor (Device Monitoring Studio) and found out:

The developer forgot to add a 0x0A (line feed) at the end of each command.
The frequency change command is implemented, but they forgot the place holder for the numeric value
After each frequency change, we must tell the radio to switch to USB mode, otherwise, it will automatically change to LSB when on 80m or higher. That’s correct for speech, but not for digi modes.
For the DTR control, there is simply no way to select a COM port in the GUI, so we must fix it in the INI file.

So first, we change the CAT commands. I replaced the Alinco DX-SR8T block in the VarAC_cat_commands.ini as follows:

[Alinco DX-SR8T]
CmdType=TEXT
PTTOn=AL~RW_PTT01[LF]
PTTOff=AL~RW_PTT00[LF]
ModeUSB=AL~RW_RFM00[LF]
ModeUSB_D=AL~RW_RFM00[LF]
ModeFM=AL~RW_RFM05[LF]
SetFreq_Data_method=TEXT
SetFreqVfoA_Cmd=AL~RW_RXF{}[LF],[WAIT:100],AL~RW_RFM00[LF]
SetFreqVfoA_param_length=8
SetFreqVfoA_hz_res=1
ReadFreqVfoA_Cmd=AL~RR_RXF[LF]
ReadFreqVfoA_Result_Data_method=TEXT
ReadFreqVfoA_Result_hz_res=1
ReadFreqVfoA_Result_Length=8
ReadFreqVfoA_Result_Freq_Start_Pos=1
ReadFreqVfoA_Result_Freq_Length=8
VarACStartCmd=
VarACExitCmd=

And in the VarAC.ini, there is a tiny block, that I changed as follows:

[DTR_RTS]
ComPort=COM5
Type=DTR

Out of the box, the argument behind „ComPort=“ was empty. That’s why the program read a NULL value. I changed it to COM5. Of course, use the COM port that is connected to your PTT/DTR.

Have fun!

DK2GB