QtSoundModem Configuration File

QtSoundModem is a port of UZ7HO’s Soundmodem so many of the configuration options transfer across to QtSoundModem with the exception of a few.

The best way to analyse the configuration is to first read John G8BPQ’s notes on the differences between QtSoundModem, and then read the official UZ7HO documentation.

Qt Port of UZ7HO’s SoundModem Download

uz7ho_soundmodem_user_guide_v114_en Download

Examples

Noteworthy Parameters

Bit Recovery

BitRecovery=0

This must be disabled for operations with a node or BBS, BitRecovery was added for keyboard-to-keyboard chats in the original UZ7HO SoundModem, as the occasional incorrect flip of a bit is not too important, however when using for mail forwarding via transfer of data through the node then this can cause severe issues by corrupting the data, so it is best left disabled if used with a node.

CW ID

CWIDCall=PE1RRR
CWIDInterval=15 
CWIDLeft=0 
CWIDRight=0 
CWIDType=1

The CWID is an optional setting to allow QTSM to take on the role of ID’ing for your station. The CWIDType options are as follows: 0=off, 1=Break-in CW, 2=FSK CW. The other options are self explanatory, please ensure you change them! 😎

Extra Decoders

NRRcvrPairs1=3 
NRRcvrPairs2=3
NRRcvrPairs3=0 
NRRcvrPairs4=0

Additional decoders are capable of improving HF operation by catching stations floating off frequency a little to the side of either ports. 3 is a reasonable number, any more and system performance will begin to be impacted.

PTT Options

HamLibHost=127.0.0.1
HamLibPort=4532
PTT=HAMLIB
PTTBAUD=19200
PTTMode=16
PTTOffString=
PTTOnString=
CM108Addr=
pttGPIOPin=17
pttGPIOPinR=17

In this example, QtSoundModem controls PTT by connecting to the HAMLIB rigctld emulator that is defined in the RADIO (RIGCONTROL) definition in bpq32.cfg.

The following rig control section of a bpq32.cfg example enables the HAMLIB rigctld emulator (the lines struck out are there to illustrate where the HAMLIB parameter goes).

RADIO 1
FLRIG 127.0.0.1:12345 HAMLIB=4532 
00:00
5,14.1023,USB
****

PTT= can be a serial port name or None/HAMLIB/GPIO/CM108

PTTMode is a qualifier and the values are

#define PTTRTS        1
#define PTTDTR        2
#define PTTCAT        4
#define PTTCM108      8
#define PTTHAMLIB    16

CM108Addr, HamLibPort, HamLibHost are used if the appropriate mode is selected.

VOX (PTT=None)
Using PTT pins on sound card interfaces based on the CM108 or CM119 Chips (CM108Addr=)
Using GPIO pin(s) on platforms like the Raspberry Pi (pttGPIOPin= / pttGPIOPinR=)
CAT Commands (see paragraph below)
HAMLIB (rigctld, either the real rigctld or the emulated rigctld in BPQ32).

For CAT you need to specify (in hex) the strings to be sent to the radio for PTTOnString and PTTOffString.

https://www.cantab.net/users/john.wiseman/Documents/QtSoundModem.html

DCD Threshold

DCDThreshold=72

The DCD threshold is usually a slider in the GUI that may need tweaking to have acceptable digital carrier detect operation, the one shown is usually a good value to start with.

Modem Selection

ModemType1=0
ModemType2=0
ModemType3=0
ModemType4=0

0 refers to the position in the modem list provided by the GUI. Depending upon which QTSM version you have this list may be different but luckily position 0 refers to AX300.

Tone Center Frequency

RXFreq1=1000 
RXFreq2=2000
RXFreq3=2300 
RXFreq4=2600

The center frequencies of tones pairs.

Enable/Disable Modems

soundChannel1=1 
soundChannel2=1
soundChannel3=0 
soundChannel4=0

The audio for both ports is sent out on one device to one radio. Two ports defined here are on the same QRG but at different center frequencies, this corresponds to the Where to find Packet on 20 meter band, Where to find Packet on 10 meter band (US & EU) and Where to find Packet on 40 meter band (EU) documentation.

Digipeater

There is an undocumented digipeater option for QtSoundModem that is for users using the UZ7HO driver rather than the KISS interface to enable digipeating.

Parameter is MyDigiCall (one for each modem) and takes a comma-separated list of digi callsigns within a comma separated delimitated with “”

MyDigiCall="G88BPQ-1,G8BPQ-2"

E.g. under each modem definition:

[AX25_A]
MyDigiCall=“PE1RRR-7,RIJEN”
…

[AX25_B]
MyDigiCall=“PE1RRR-7,RIJEN”
…

[AX25_C]
MyDigiCall=“PE1RRR-7,RIJEN”
…

[AX25_D]
MyDigiCall=“PE1RRR-7,RIJEN”
…

Alternatively if you want to let BPQ handle the DIGI feature, It is possible to enable both the AGWHost and KISS interfaces in QtSoundModem, but you need to be careful to make sure the KISS port configured in bpq32.cfg can not accept any connections otherwise you will get both QtSoundModem and BPQ responding to a connect request.

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