A hotspot is simply an internet gateway to a particular DMR network (Brandmeister/Phoenix/DMR+ etc). You would use a hotspot when you either don’t have a DMR repeater nearby, or simply don’t want to tie it up for any length of time. This is a great idea if you like to spend a lot of time on different Talkgroups as it does not tie up a Time Slot on your local repeater and allows others who may not own a hotspot to make use of the repeater.
Many hotspots are capable of multiple modes as well, such as D-Star, P25, DMR+, YSF and NXDN.
The DV-Mega is a very popular hotspot which can either be connected to an Arduino Uno Board, a BlueStack board or more commonly to a Raspberry Pi computer as a Pi-Hat as shown below.
Shown below is the DV-Mega with a BlueStack board which allows you to use a mobile phone or tablet with Bluetooth and use the BlueDV app to connect to the Internet and DMR Network.
Below is Martin MM0DUN’s duplex hotspot complete with a Nextion touch-screen with access to all the information on the RasPi, frequency and callers.
Below is a photo of a Raspberry Pi with a UHF DV-Mega HAT with a Nextion 3.5″ screen connected via a USB-TTL Adapter showing activity.
You can also create a simplex hotspot using a mobile radio, it is usually best to use a commercial radio for this purpose as they are built for the frequent switching and for constant use. Using an amatuer radio you will find it will work fine but it may not last and would not be a cost-effective solution longterm.
Above we have a home-brew MMDVM simplex hotspot.