Virginie is the Project Name I gave to this repeater when first I came to be the repeater keeper, when the first repeater had solid logic and I called that Marie-Anne.

The first versions of SVXLink were tested at home on a pair of Kenwood TK 709 transceivers into a dummy load. Because SVXLink is based upon a Linux operating system, the whole project became an education package, as despite my computer background Linux had never been on the program. In addition to Linux, was C++, TCL and later JSON.

In addition to the logic control imparted to the repeater there was the added benefit of Voice Identification with all the various modules within the package. The French people are very particular when it comes to language being used on the radio, so I found a very interest set of programs with which to build all the necessary phrases used within the logic, all 450 of them.

The voice that I found was called Virginie, hence the name of the project.

The next step was a suitable interface to interact with the Raspberry Pi, the sound card, and the two receivers.

The simplified diagram for an interface dedicated to the Raspberry Pi and the GPIO ports

This interface was initially constructed on Vero-Board, but later models were developed by Juan F8ASB on purpose built PCBs.

The interface gave fully adjustable sound in and out, and the possibility of flexibility of COS operation too.

All that was necessary was the choice of which pins to use on the GPIO on the Raspberry Pi. There is a wealth of information on the GPIO structure on the internet. It was just a matter of which to choose for the COS and PTT, and make those adjustments in the software after compilation time.

The first build of the repeater was made on a Raspberry Pi Model B, with a standard SD Card. Raspbian Wheezy was the operating system, built by installing it via a Windows computer, then connecting the Raspberry to the local network and booting into the terminal.

Like many things Linux, it is always necessary to update and upgrade the Operating system before installing packages, and they too require packages not falling part of the original operating system. SVXLink is likewise subject to these unwritten rules.

Like a lot of other packages, there are four stages, the download, the compilation, the build, and the install. The Download is accomplished by “git” from the Github. The compilation requires the expansion and preparation of the downloaded files into a structure that can be then ‘built’ into a form that can then be installed into place in amongst the files, becoming part of the SVXLink operating system. Once built, it has to be formally introduced by ldconfig. At this time the package is dormant and non running, as again some further stages need tailoring for the installation to follow.

Things like call signs, co-ordinates of the site, audio levels and GPIO configurations have to be set. Power levels and power supplies were also important, as both 12V for the transceivers and 5v for the Raspberry Pi both at comfortable levels.

Naturally the Raspberry Pi has developed, and the repeater tests were moved up to a Raspberry Pi B+ giving a lot move performance, on a microSDCard. Despite a larger GPIO array moved up to 40 pins this really had no bearing.

After extensive testing, and an almost catastrophic failure on the original repeater, Marie-Anne was retired and Virginie went into service, with two Motorola GM350 128 Channel transceivers. These were preferred as flat audio in and out is already available on the 16 Pin Accessory socket on the rear of the radio.

Early build
Almost Ready
Marie-Anne prior to retirement.
Viriginie’s Vari-Notch cavities, three for transmit and three for receive.

The one stumbling block for the operation of Virginie was the need for internet. There was none. However this became an interesting project on its own. So with the provision of 2.4 Giga-hertz between the source and the repeater site was important. With Parabolic dishes on either end of 45 kilometres it was nothing short of amazing that the bandwidth was sufficient not only for the regulation of the repeater but the passage of the data for EchoLink, and other systems as well.

Currently F5ZGM is running on a Raspberry Pi 2B, and serves an immense area of coverage over three or four departements. It was better, but the permanent break-down of the 250 Watt amplifier reduces the capabilities somewhat.

Virginie now has 12 Watts output on a colinear at 30 Metres from an Altitude of 785 Metres, and sharing the internet with a Radar24 Installation, anAPRS Digi-peater, A 51 MHz Repeater, a 29 MHz Simplex repeater, and a UHF DMR repeater, and a commercial system for which we provide the internet connection.

Next Chapter some technical information from the SVXLink installation.

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