DMR JOTSPOT PLUS
DMR JOTSPOT FREE

Important! If you see anything like on the picture below, generally MMDVM PCBs without any SMA antenna connectors, DO NOT BUY!! What you probably see is a PCB for a proper repeaters with external radios (very often Motorola DM380 etc). Case (the one from the picture probably is too small for the set).Raspberry Pi Zero WH (W – wireless, H – soldered header – pins to connect together with the repeater).simplex MMDVM repeater with OLED display.So on the picture from top left we can see: Also some repeaters do not work with Pi 4, so Pi 3 is a safe maximum. You can also buy Pi 3 or even 4 but they are too powerful for the purpose – money wasting. You need to buy a repeater and Raspberry Pi (usually Zero W).

DMR JOTSPOT FREE

Instead of buying ready for use, hassle free box, you can assemble your own one. I definitely recommend the duplex one! The duplex hotspot let you divide (this is the way how I did it!) very busy groups and put them on slot 1, and some local groups to keep them on slot 2. First one (left) is a simplex one, the other one (right) is a duplex one.

DMR JOTSPOT PLUS

They both are made from Raspberry Pi Zero W and repeater PCB plus OLED display. So, when you type DMR hotspot on Amazon you get: optionally the hotspot can be equipped with OLED display, however I do not find it useful at all.another PCB with the MMDVM repeater and a radio UHF hardware (transceiver).a Raspberry Pi (usually Zero W, W – means wireless, equipped with WiFi and Bluetooth, Raspberry with no letter has got no wireless connections).Before we start, I would like to mention that every single DMR hotspot MUST be made from: I had to spend another 2h to make sure I am buying the right thing.Īnyway, just in case somebody needs a small help would like to talk what actually you can buy. at the country side) the result could be much better! So I very quickly typed hotspot on Amazon and… I did not know what to buy. A very quick research gave me the answer – it is a extremely small home UHF DMR repeater, using only 10mW power! Actually, with my handheld radio and very small (5cm) antennas on the hotspot, I found it has roughly 300 meters range – amazing for using this around home! The 300 meters range was for the signal going through a lot of houses, so I can only guess with a direct visibility (eg. Then, I heard a lot of people saying they that they use a DMR hotspot. However, the repeater sometimes was too busy and I could not use my favourite groups. So to get the access to the network I was using a local DMR repeater. I even managed to flash the radio with 200k contacts, using Virtual Machine – ARTICLE HERE. My first steps with DMR were with TYT MD380 – a very popular DMR radio. So when I decided to join the DMR team, I struggled a bit to understand how the system works. I actually had roughly 15 years long break from amateur radio! So I decided to come back when a lot of people already started the DMR adventure. It has extended the range of 300 meters to way over 1 kilometer and some locals are even using it as a convenient repeater when setup at my base location.Just a few months ago I did not know too much about the DMR system. Built a prototype and never looked back, this antenna is such and improvement, it now goes with me wherever my hotspot goes. Received a stiff piece of wire which was non magnetic and had a brass sheen to it. Went to the local welding workshop and asked if they welded anything other than iron, and if so, could I please have a two meter session of this wire. After discussing this with friends, a suggestion was made to look into MIG welding wire as building material. It was a great performance improvement, but I was still not happy. Next I tried metal guitar strings, very easy to construct and it maintains its shape, even if packed with other goods in a rucksack or suitcase, but difficult to solder (the nickel outer layer would pull loose from the string in time). I understand that iron is not agood material to use for antenna elements, but electrical copper wire is just to weak and easily bends and eventually after to much bending will break. Next challenge was to make it simple to transport and difficult to damage (as in just throw it in a suitcase with everything else and go). The solution was actually so simple and there is even gain to be achieved, just a more than 2.5 db. I then tried rectangles and it was an instant winner with easy spot on matching. Thought of trying loops, but left it at thoughts as it made no sense. Tried triangles, but got weird matching results, Squares produced about twice the impedance of 50 Ohm I wanted. Got some electrical copper wire and started experimenting. What if I could use old principle HF antenna concepts, like full-wave antennas.

Dmr jotspot