Every logic start with this line:LOGICS=RepeaterLogic,IntercomLogic You find in svxlink.conf the configuration for receivers Rx1,Rx2 and transmitters Tx1,Tx2

First you need to create IntercomLogic.tcl file

Go to the specific directory:

cd /usr/share/svxlink/events.d/

Duplicate the file SimplexLogic.tcl into IntercomLogic.tcl

sudo cp SimplexLogic.tcl IntercomLogic.tcl

ls to check if the file is here and write correctly.

Edit the file IntercomLogic.tcl sudo nano IntercomLogic.tcl

Modify the name of namespace: namespace eval IntercomLogic (line 12)

Beyond 3 radio the Raspberry starts to have hardware limits, the sound is strongly degraded.

Edit svxlink.conf and modify same this sample sudo nano /etc/svxlink/svxlink.conf

svxlink.conf

###############################################################################
#                                                                             #
#                Configuration file for the SvxLink server                    #
#                                                                             #
###############################################################################
 
[GLOBAL]
#MODULE_PATH=/usr/lib/arm-linux-gnueabihf/svxlink
LOGICS=RepeaterLogic,IntercomLogic
CFG_DIR=svxlink.d
TIMESTAMP_FORMAT="%c"
CARD_SAMPLE_RATE=16000
#CARD_CHANNELS=1
#LOCATION_INFO=LocationInfo
LINKS=IntercomLink
 
 
[RepeaterLogic]
TYPE=Repeater
RX=Rx1
TX=Tx1
#MODULES=ModuleHelp,ModuleParrot,ModuleEchoLink,ModuleTclVoiceMail
MODULES=ModuleHelp,ModuleParrot
CALLSIGN=F1ZKA
SHORT_IDENT_INTERVAL=15
LONG_IDENT_INTERVAL=60
#IDENT_ONLY_AFTER_TX=4
#EXEC_CMD_ON_SQL_CLOSE=500
EVENT_HANDLER=/usr/share/svxlink/events.tcl
DEFAULT_LANG=fr_FR
RGR_SOUND_DELAY=0
REPORT_CTCSS=136.5
#TX_CTCSS=SQL_OPEN
MACROS=Macros
#SEL5_MACRO_RANGE=03400,03499
FX_GAIN_NORMAL=0
FX_GAIN_LOW=-12
#QSO_RECORDER=8:QsoRecorder
#NO_REPEAT
IDLE_TIMEOUT=15
OPEN_ON_1750=500
#OPEN_ON_CTCSS=136:2000
#OPEN_ON_DTMF=*
#OPEN_ON_SQL=5000
#OPEN_ON_SEL5=01234
#OPEN_SQL_FLANK=OPEN
#OPEN_ON_SQL_AFTER_RPT_CLOSE=10
IDLE_SOUND_INTERVAL=3000
#SQL_FLAP_SUP_MIN_TIME=1000
#SQL_FLAP_SUP_MAX_COUNT=10
#ACTIVATE_MODULE_ON_LONG_CMD=4:EchoLink
#IDENT_NAG_TIMEOUT=15
#IDENT_NAG_MIN_TIME=2000
#ONLINE_CMD=998877
#STATE_PTY=/var/run/svxlink/state
 
[IntercomLogic]
TYPE=Simplex
RX=Rx2
TX=Tx2
MODULES=ModuleHelp,ModuleMetarInfo,ModuleParrot
CALLSIGN=F5XYZ
SHORT_IDENT_INTERVAL=15
LONG_IDENT_INTERVAL=60
EVENT_HANDLER=/usr/share/svxlink/events.tcl
DEFAULT_LANG=fr_FR
RGR_SOUND_DELAY=0
MACROS=Macros
FX_GAIN_NORMAL=0
FX_GAIN_LOW=-12
ONLINE_CMD=123456789
#MUTE_RX_ON_TX=1
#MUTE_TX_ON_RX=1
 
[IntercomLink]
CONNECT_LOGICS=RepeaterLogic,IntercomLogic:99
DEFAULT_ACTIVE=1
 
[Macros]
1=EchoLink:9999#
9=Parrot:0123456789#
03400=EchoLink:9999#
 
[QsoRecorder]
REC_DIR=/var/spool/svxlink/qso_recorder
#MIN_TIME=1000
MAX_TIME=3600
SOFT_TIME=300
MAX_DIRSIZE=1024
#DEFAULT_ACTIVE=1
#TIMEOUT=300
#QSO_TIMEOUT=300
#ENCODER_CMD=/usr/bin/oggenc -Q \"%f\" && rm \"%f\"
 
[Voter]
TYPE=Voter
RECEIVERS=Rx1,Rx2,Rx3
VOTING_DELAY=200
BUFFER_LENGTH=0
#REVOTE_INTERVAL=1000
#HYSTERESIS=50
#SQL_CLOSE_REVOTE_DELAY=500
#RX_SWITCH_DELAY=500
 
[MultiTx]
TYPE=Multi
TRANSMITTERS=Tx1,Tx2,Tx3
 
[NetRx]
TYPE=Net
HOST=remote.rx.host
TCP_PORT=5210
#LOG_DISCONNECTS_ONCE=0
AUTH_KEY="Change this key now!"
CODEC=S16
#SPEEX_ENC_FRAMES_PER_PACKET=4
#SPEEX_ENC_QUALITY=4
#SPEEX_ENC_BITRATE=15000
#SPEEX_ENC_COMPLEXITY=2
#SPEEX_ENC_VBR=0
#SPEEX_ENC_VBR_QUALITY=4
#SPEEX_ENC_ABR=15000
#SPEEX_DEC_ENHANCER=1
#OPUS_ENC_FRAME_SIZE=20
#OPUS_ENC_COMPLEXITY=10
#OPUS_ENC_BITRATE=20000
#OPUS_ENC_VBR=1
 
[NetTx]
TYPE=Net
HOST=remote.tx.host
TCP_PORT=5210
#LOG_DISCONNECTS_ONCE=0
AUTH_KEY="Change this key now!"
CODEC=S16
#SPEEX_ENC_FRAMES_PER_PACKET=4
#SPEEX_ENC_QUALITY=4
#SPEEX_ENC_BITRATE=15000
#SPEEX_ENC_COMPLEXITY=2
#SPEEX_ENC_VBR=0
#SPEEX_ENC_VBR_QUALITY=4
#SPEEX_ENC_ABR=15000
#SPEEX_DEC_ENHANCER=1
#OPUS_ENC_FRAME_SIZE=20
#OPUS_ENC_COMPLEXITY=10
#OPUS_ENC_BITRATE=20000
#OPUS_ENC_VBR=1
 
[Rx1]
TYPE=Local
AUDIO_DEV=alsa:plughw:1
AUDIO_CHANNEL=0
SQL_DET=GPIO
SQL_START_DELAY=0
SQL_DELAY=0
SQL_HANGTIME=0
#SQL_EXTENDED_HANGTIME=1000
#SQL_EXTENDED_HANGTIME_THRESH=15
#SQL_TIMEOUT=600
#VOX_FILTER_DEPTH=20
#VOX_THRESH=1000
#CTCSS_MODE=2
#CTCSS_FQ=136.5
#CTCSS_SNR_OFFSET=0
#CTCSS_OPEN_THRESH=15
#CTCSS_CLOSE_THRESH=9
#CTCSS_BPF_LOW=60
#CTCSS_BPF_HIGH=270
#SERIAL_PORT=/dev/ttyS0
#SERIAL_PIN=CTS
#SERIAL_SET_PINS=DTR!RTS
#EVDEV_DEVNAME=/dev/input/by-id/usb-SYNIC_SYNIC_Wireless_Audio-event-if03
#EVDEV_OPEN=1,163,1
#EVDEV_CLOSE=1,163,0
GPIO_SQL_PIN=gpio19
#PTY_PATH=/tmp/rx1_sql
#HID_DEVICE=/dev/hidraw3
#HID_SQL_PIN=VOL_UP
#SIGLEV_DET=TONE
SIGLEV_SLOPE=1
SIGLEV_OFFSET=0
#SIGLEV_BOGUS_THRESH=120
#TONE_SIGLEV_MAP=100,84,60,50,37,32,28,23,19,8
SIGLEV_OPEN_THRESH=30
SIGLEV_CLOSE_THRESH=10
DEEMPHASIS=0
#SQL_TAIL_ELIM=300
#PREAMP=6
PEAK_METER=1
DTMF_DEC_TYPE=INTERNAL
DTMF_MUTING=1
DTMF_HANGTIME=100
DTMF_SERIAL=/dev/ttyS0
#DTMF_PTY=/tmp/rx1_dtmf
#DTMF_MAX_FWD_TWIST=8
#DTMF_MAX_REV_TWIST=4
1750_MUTING=1
#SEL5_DEC_TYPE=INTERNAL
#SEL5_TYPE=ZVEI1
#FQ=433475000
#MODULATION=FM
#WBRX=WbRx1
 
[WbRx1]
#TYPE=RtlUsb
#DEV_MATCH=0
#HOST=localhost
#PORT=1234
#CENTER_FQ=435075000
#FQ_CORR=0
#GAIN=0
#PEAK_METER=1
#SAMPLE_RATE=960000
 
[Tx1]
TYPE=Local
AUDIO_DEV=alsa:plughw:1
#AUDIO_DEV=alsa:plug:plugequal
AUDIO_CHANNEL=0
PTT_TYPE=GPIO
#PTT_PORT=/dev/ttyS0
PTT_PIN=gpio16
#HID_DEVICE=/dev/hidraw3
#HID_PTT_PIN=GPIO3
#SERIAL_SET_PINS=DTR!RTS
#PTT_HANGTIME=1000
TIMEOUT=300
TX_DELAY=10
#CTCSS_FQ=136.5
#CTCSS_LEVEL=9
PREEMPHASIS=0
DTMF_TONE_LENGTH=100
DTMF_TONE_SPACING=50
DTMF_DIGIT_PWR=-15
#MASTER_GAIN=0.0
 
[Rx2]
TYPE=Local
AUDIO_DEV=alsa:plughw:1
AUDIO_CHANNEL=0
SQL_DET=GPIO
GPIO_SQL_PIN=gpio18
SQL_START_DELAY=60
SQL_DELAY=0
SQL_HANGTIME=2000
SQL_TIMEOUT=300
DEEMPHASIS=0
#SQL_TAIL_ELIM=0
PREAMP=0
PEAK_METER=1
DTMF_DEC_TYPE=INTERNAL
DTMF_MUTING=1
DTMF_HANGTIME=100
#1750_MUTING=0
 
[Tx2]
TYPE=Local
AUDIO_DEV=alsa:plughw:1
AUDIO_CHANNEL=0
PTT_TYPE=GPIO
PTT_PIN=gpio17
#PTT_HANGTIME=1000
TIMEOUT=600
TX_DELAY=10
PREEMPHASIS=0
DTMF_TONE_LENGTH=100
DTMF_TONE_SPACING=50
DTMF_DIGIT_PWR=-15
 
 
 
[LocationInfo]
APRS_SERVER_LIST=euro.aprs2.net:14580
#STATUS_SERVER_LIST=aprs.echolink.org:5199
#LON_POSITION=12.10.00E
#LAT_POSITION=51.10.00N
#CALLSIGN=EL-DL0ABC
#FREQUENCY=438.875
#TX_POWER=8
#ANTENNA_GAIN=6
#ANTENNA_HEIGHT=20m
#ANTENNA_DIR=-1
PATH=WIDE1-1
BEACON_INTERVAL=10
#TONE=136
COMMENT=SvxLink by SM0SVX (svxlink.sourceforge.net)

Find an additional article on the site F8ASB.COM http://blog.f8asb.com/2017/09/23/svxlink-vers-une-solution-intercom-1ere-partie/