Analogue 4 port gateway with first 3 x ports populated, registering to Voyager SIP services. 

Many thanks to Matevz Persak from Ayone( for sharing the sample config.

#                                                                #
# SN4114/JS/EUI                                                  #
# R6.9 2017-05-04 H323 SIP FXS FXO                               #
# 2017-09-05T15:38:34                                            #
# Update all fields with !!                                                          #

cli version 3.20
administrator !!USERNAME password !!YOURPASSWORD
clock local default-offset +12:00
dns-client server
dns-client server !!DNSSERVERSECONDARY
webserver port 80 language en
sntp-client server primary port 123 version 4
system hostname !!HOSTNAME


  ic voice 0
    low-bitrate-codec g729

profile ppp default

profile call-progress-tone NZ_Dialtone
  play 1 5000 400 -15

profile call-progress-tone NZ_Alertingtone
  play 1 400 400 -15 450 -15
  pause 2 200
  play 3 400 400 -15 450 -15
  pause 4 2000

profile call-progress-tone NZ_Busytone
  play 1 500 400 -15
  pause 2 500

profile call-progress-tone NZ_SDTone
  play 1 10000 425 -19 620 -19

profile call-progress-tone NZ_Callwaiting
  play 1 200 400 -15
  pause 2 200

profile call-progress-tone NZ_Releasetone
  play 1 250 400 -15
  pause 2 250

profile tone-set default
profile tone-set NZ
  map call-progress-tone dial-tone NZ_Dialtone
  map call-progress-tone ringback-tone NZ_Alertingtone
  map call-progress-tone busy-tone NZ_Busytone
  map call-progress-tone waiting-tone NZ_Callwaiting
  map call-progress-tone release-tone NZ_Releasetone
  map call-progress-tone congestion-tone NZ_Releasetone

profile voip default
  codec 1 g711alaw64k rx-length 20 tx-length 20
  codec 2 g711ulaw64k rx-length 20 tx-length 20

profile pstn default

profile ringing-cadence default
  play 1 1000
  pause 2 4000

profile sip default
  no autonomous-transitioning

profile aaa default
  method 1 local
  method 2 none

context ip router

  interface IF_LAN
    ipaddress dhcp

context cs switch
  digit-collection timeout 3

  routing-table called-e164 RT_FXS_TO_SIP
    route T dest-interface IF_SIP

  routing-table calling-e164 RT_SIP_TO_PSTN
    route default dest-service SV_HUNT_PSTN

  interface sip IF_SIP
    bind context sip-gateway GW_SIP
    route call dest-table RT_SIP_TO_PSTN
    remote !!VOYAGERSIPREALM(similar to 5060
    address-translation outgoing-call from-header user-part fix !!PHONENUMBER host-part fix !!VOYAGERSIPREALM
    use profile tone-set NZ

  interface fxs IF_FXS_0
    route call dest-table RT_FXS_TO_SIP
    no call-waiting
    use profile tone-set NZ

  interface fxs IF_FXS_1
    route call dest-table RT_FXS_TO_SIP
    no call-waiting
    use profile tone-set NZ

  interface fxs IF_FXS_2
    route call dest-table RT_FXS_TO_SIP
    no call-waiting
    use profile tone-set NZ

  service hunt-group SV_HUNT_PSTN
    drop-cause normal-unspecified
    drop-cause no-circuit-channel-available
    drop-cause network-out-of-order
    drop-cause temporary-failure
    drop-cause switching-equipment-congestion
    drop-cause access-info-discarded
    drop-cause circuit-channel-not-available
    drop-cause resources-unavailable
    drop-cause user-busy
    route call 1 dest-interface IF_FXS_0
    route call 2 dest-interface IF_FXS_1
    route call 3 dest-interface IF_FXS_2

context cs switch
  no shutdown

authentication-service AUTH_SVC
  username !!PHONENUMBER password !!PASSWORD

location-service LOCATION_SVC

  identity !!PHONENUMBER

    authentication outbound
      authenticate 1 authentication-service AUTH_SVC username !!PHONENUMBER

    registration outbound
      registrar !!VOYAGERSIPREALM
      lifetime 3600
      register auto
      retry-timeout on-system-error 10
      retry-timeout on-client-error 10
      retry-timeout on-server-error 10

context sip-gateway GW_SIP

  interface LAN
    bind interface IF_LAN context router port 5060
    spoofed nat-address auto

context sip-gateway GW_SIP
  bind location-service LOCATION_SVC
  no shutdown

port ethernet 0 0
  medium auto
  encapsulation ip
  bind interface IF_LAN router
  no shutdown

port fxs 0 0
  use profile fxs nz
  encapsulation cc-fxs
  bind interface IF_FXS_0 switch

port fxs 0 1
  use profile fxs nz
  encapsulation cc-fxs
  bind interface IF_FXS_1 switch
  no shutdown

port fxs 0 2
  use profile fxs nz
  encapsulation cc-fxs
  bind interface IF_FXS_2 switch
  no shutdown

port fxs 0 3