Monday, November 20, 2017


Digital Hotspots

Two hotspots are in use in the EI5DD QTH. The Shark RF Openspot and the DVMega bluestack. They are both excellent Hotspots and result in an excellent signal through the Netork to which they are connected. Other Hotspots include MMDVM and the DV4Mini.

A Digital Hotspot is a standalone digital radio IP gateway connected either directly to the Internet router via WiFi, Bluetooth or direct connection. Effectively, it is a small transceiver which transmits auudio derived from the internet connected to an appropriate Network such as Brandmeister, YSF or FCS.

The DVMega comes in two forms, either UHF only or dual band UHF and VHF.

The DVMega comes with a USB programming lead allowing the Firmware to be updated as required and the lead will double as a direct connection to a computer, Raspberry pi or windows,  or Android phone/tablet or is used to power the device. 

The initial set up of the device on a  windows system is simple by filling in the appropriate boxes with the reuired information and ensuring the correct frequency

A similar, but simple, screen is available on the Andriod tablet or Phone.

Using Pi-Star on the Raspberry Pi

Pi-Star is a custom, pre-configured SD Card image for the Raspbperry Pi (and other ARM based single board computers). Pi-Star is the whole image, it is made up of a number of software components, but Pi-Star is the sum of its parts. The major components that make up Pi-Star include the excellent software stacks by Jonathan Naylor (G4KLX) & others - MMDVMHost / DStarRepeater and associated tools / programs. This software stack is fairly feature complete (it's not complete, until its complete....) and contains many innovations and tools that are usefull to hotspot operators and repeater keepers alike.

Pi-Star may be downloaded >>>> click HERE

Simply download the image to the laptop or desktop and use a program such "Etcher" to flash the image to a micro SD card. Insert the SD card into the Raspberry Pi and apply power and the Raspberry Pi will boot up straight into Pi-Star. Fill in the station details in the configuration page as shown. It should be noted that it does need a Raspberry Pi 3B  for best results. 

For the DV Mega configure each section as shown and click on "Apply Changes" before moving to next section.

Select the modes on which you wish to operated by clicking on the appropriate sliders. In this case both DMR and Fusion have been selected

Fill in the Callsign, DMR ID and other appropriate details in this section and apply changes. The frequency selected may be any of your own choice. By entering the LAT/LON details, the location of the station will appear on the Brandmeister Map.

For each Digital Mode, it is necessary to set up the default  server and in the DMR Configuration in this case the Default Server is the Ireland Call Talk Group 2722. Again do not forget to click on the Apply Changes button.

The Fusion also needs to be set up with default Server and APRS server. Apply changes.

Finally to Network Configuration. After setting the Firewall as shown, the WiFi can be set up as in the second panel. Once set up the dashboard will be accessible via the WiFi system. provided a password has been set up in the last panel. I generally set up the unit with an Ethernet connection but if portable or mobile the set-up can be used on the WiFi system with little noticeable difference in performance. 

If this system is to get constant use as a multimode Gateway, it is advisable to acquire a set of heatsinks for the main chips on the RPi motherboard, two on top and one on the underside. A cooling fan as also a good  finishing touch. This will keep the Raspberry Pi running cool if left running 24/7/365. As a home hotspot this would not be a priority.

Finally this is the activity Screen on the Dashboard. 

This is the set up as used on my holiday in the UK. The router is a 4G router with 4 ethernet ports as well as being WiFi. I was testing the router with a view to its use on a gateway and possibly a repeater in a remote location. To date it has worked well.

The system below shows the Raspberry Pi in a case with a Fan to keep the system cool in conjunction with heat sinks on the processor chips. Sitting on top of the Raspberry Pi, is the DVMega.

The system has been in use for approximately one month without any problems so I can recommend this set up.

When operating Yaesu Fusion, it is possible to press the Wires-X button on the transceiver and the Hotspot will transmit a list of reflectors allowing one to select the reflector of choice in much the same way as one can do on the Wires-X network using a Fusion Repeater or a Fusion Gateway.

Shark Openspot to follow soon.