February 2021 – N4MI Ham Radio

I have been casually using DMR, D-STAR and YSF (Yaesu System Fusion) modes for a couple of years, using a ZUMSpot. The ZUMSpot is a small board that sits on a Raspberry Pi Zero W. It incorporates a Multimode Digital Voice Modem (MMDVM) and a 10mW UHF transceiver that operates YSF, DMR, YSF2DMR, D-Star, P25 and NXDN modes. The ZUMSpot uses Pi-Star digital voice software. Pi-Star is a custom, pre-configured SD Card image for the Raspbperry Pi, with configuration and operation performed through a web browser. The Amateur Radio Notes website has an excellent tutorial on setting up and configuring Pi-Star. While the Pi-Star configuration appears daunting at first, it is easy to set up by following the tutorial. There are also several videos on YouTube with instructions for configuring Pi-Star.

A few days ago, I was attempting to update the Pi-Star software and the ZumSpot firmware, but kept seeing errors during the firmware update. After several attempts to update the firmware, the ZumSpot wasn’t operating properly*, so I decided to purchase an openSPOT 3, which is made by SharkRF in Estonia.

The openSPOT3 is a battery powered, portable, standalone digital radio internet gateway (aka hotspot). The openSPOT 3 is also configured through a web interface, but the interface and steps for configuration are different than Pi-Star’s. The openSPOT 3 user manual is a web page that is updated frequently when there are firmware updates or features added to the device. Having learned the basics of DMR, D-STAR, and YSF with the ZUMSpot, I found configuration of the OPENSpot 3 to be fairly easy.

* After I had the openSPOT 3 up and running for a few days, I decided to attempt the ZUMSpot firmware upgrade again. It turns out I had missed a step in my earlier attempts, and this time the update was successful. So now I have two MMDVMs!

Both the ZUMSpot and OpenSPOT 3 are excellent MMDVMs. Both are capable of operating the most popular digital voice modes using a DMR, D-STAR or C4FM radio. Also, they both require a wi-fi connection and are configured through a web interface. The openSPOT 3 is great for portable operations since it has a built-in battery and the configuration web page works very well on a mobile phone web browser. Since the ZUMSpot is based on a Raspberry Pi Zero W, it could also be used portable with a USB power bank. The openSPOT 3 costs a bit more more than the ZUMSpot. There are also many other MMDVMs on the market, including inexpensive generic boards and kits available on Amazon and eBay. Digital voice modes with MMDVMs are a great way to talk to hams from all over the world using a VHF/UHF digital radio and an Internet connection.

The Pi-Star configuration panel is used to enter all of the necessary settings for the MMDVM to operate properly.

The Pi-Star Dashboard displays a call log and the current status of the MMDVM.

The Pi-Star Administration panel displays some additional status information, and options to change some of the settings for the digital mode currently in use.

The openSPOT 3 has a “Quick Setup” page to configure the openSPOT3 with the transceiver and connect to the preferred network.

The openSPOT 3 status page and call log – you can see information about the openSPOT3’s current status, and listen to call audio on this page.

ZUMSpot in D_STAR mode with Kenwood TH-D74

Both the ZUMSpot and openSPOT 3 can be configured to send your station location via an APRS server

A local ham friend shared a link with me for Hamshack Hotline, which is a free dedicated VOIP service for the ham radio community. In order to get on this network, I purchased a used Cisco SPA504G IP phone from eBay for $29. There are several other IP phones that will work with the service, but the SPA504G works great, and the price was right! It is important when purchasing a used phone to ensure that it is unlocked. The Hamshack Hotline website has all the information necessary to get started.

Once I received the phone, and connected it to my home network, I followed the instructions on the web page, and submitted a ticket for a new line using the HHOPS Help Desk. The Help Desk web page also includes a knowledge base and downloadable documents that are a great help for installing an IP phone on their network.

Within a couple of days, I had a response from the Help Desk team with my new HH phone number, and a link to a provisioning document for my phone. The instructions were easy to follow, and the team has created a process for provisioning that is nearly foolproof. I say nearly because I did have a slight issue with my home network, but the Help Desk team came through again and got me up and running very quickly!

My Hamshack Hotline phone number is 11642.