DMR Repeater F1ZSX

DMR repeater in UHF band

Repeater under construction

Characteristics:

  • TX frequency: 439.8875 MHz
  • RX frequency: 430.4875 MHz (-9.4 Mhz)
  • TX Power 25W
  • Collinear Antenna
  • Location: JN33NP
  • ID CSS7: 208146
  • Colour code: 1
  • Sysop: F1ATB
  • Transmitter: GM360 Motorola (Ebay)
  • Receiver: GM360 Motorola
  • Hardware MMDVM Pog
  • Firmware MMDVM
  • Master DMR: BM France 2082

Hardware

MMDVM pog

The MMDVM pog modem mounted on a Raspberry pi 3 B allows direct interconnection with the Motorola GM360s used for transmission and reception. The 2 adjustable resistors on the card allow the adjustment of audio input and output levels.

GM360 Motorola

The transmitting GM360 is cooled by a fan started with the PTT control via a relay.

The connection of the transmitter and the receiver on the same antenna is done via a UHF duplexer bought in China via Ebay. When ordering you give the 2 frequencies and it is delivered to you set.

Software

On the Raspberry Pi, the Pi-Star software manages the whole.

Configuring the Pi-Star for the MMDVM Pog card

To program the 2 Motorola GM360s, use the CPS version R03.11.16. The F1ZSX GM360 programming file can be downloaded here.

Cable to program the Motorola GM360

Note that under the callsign F1ZSX there are 2 relays, one DMR in UHF which is described above and one analog in VHF.