Built a D-STAR compatible repeater

onathan has created a piece of software to act as a controller for both analog and D-STAR repeaters.  It runs on Windows and Linux and has a minimum of additional components.

You need the typical radios, duplexer, antenna and so forth to build the repeater.  Then you add:

• Linux or Windows Computer
• Cheap soundcard (I use a cheap < US$8 USB sound fob -- you want cheap, no filtering)
  
• PTT/COR device (Velleman board, Serial port, or URI)

Jonathan's software, found in the files section of pcrepeatercontroller Yahoo! group,  does the rest.  It is the GMSK modem and the control logic for the D-STAR repeater.

After obtaining a Velleman (VM110 the assembled version of the K8055 board kit),  I first tried this with some Friendcom UHF 301 radios.  My documentation isn't that good on these and they were a bit problematic, though I at least got them to sort of work, but the output signal wasn't usable -- probably my fault rather than the radios.  I decided then to try a couple of Yaesu radios, a FT817 for the receiver and an FT847 for the transmitter (they were handy).

Using the standard 6-pin DIN "packet" connector on the back of each radio, I was able to connect them to the USB soundcard and a Velleman VM100 USB project board for COR and PTT.Both radios were configured for 9600 baud packet operation.

Within Jonathan's D-STAR repeater program, I had to configure my repeater callsign NW7DR  B and tell it I was using the Velleman board (his software now supports a serial port or the URI Board for COR/PTT) and set the COR to use inverted logic and the transmitter to invert the signal.  Once this was all put together, a little twiddling with levels on the audio and it just worked! 

I strapped this together in a couple of hours and the coax is cheap stuff so I have a fair amount of desense so no real range, but around the house it is beautiful.

BTW, this code can also talk to a gateway to interconnect with other D-STAR repeaters.

Loads of fun