AURSINCMMDVM Duplex Hotspot Module Dual Hat V1.5.2 Support P25 DMR YSF NXDN DMR Slot 1 + Slot 2 for Raspberry Pi, Pi Zero with USB Port (Without OLED)

I was trying to find a well made MMDVM duplex board and I spent over a week doing research, the popular auction site had hundreds of them, some for half the price as this, but those boards looked cheaply made and did not specify any specifications or instructions. I wasn't going to waste my time waiting weeks for a board to arrive from China and up getting something that might not work. This board works quite well with a Pi 3 B+, which is what I recommend using since it has the horsepower to process everything. With that said, once you get to the point where you upgrade the firmware on this board, you can easily do so without soldering anything. Take an alligator/crocodile clip and file the teeth down on one side of the clip, making it flat, then for the other side of the clip, take some heat shrink tubing and slip it over and heat it up. Do this 2 or 3 times. (electrical tape should work too) Needless to say, you take the clip and clamp it on the board where the flash jumper traces are. This is much better than soldering. Boot it up, use SSH to issue the firmware upgrade commands, power down, remove the clip and then power it back on again. Done!

This hat just works. It works right out of the package. It works on a RPI 4B 8meg PIE. It even works without a firmware flash. comes with 1.4.7 and flash to 1.5.2. Did i mention that this is my second hat in one week and everything just works. SHY Store is the place to buy from on Amazon. They have treated me well and I will buy from them without worry. The temp in my RPI 4B is 38c/100f. That works for me.If i had known that these duplex MMDVM boards worked on RPI 4b with 8 meg I would have not purchased the 3b+ I have for the first one.And this MMDVM Duplex hat has connectors for Nextion screens and a few more ports.Both my MMDVM Duplex setups have been rock solid with Brandmister and TGIF, not one problem.Did i mention that it says it doesnt work with Raspberry pie 4B, but it does.If your board is hard to flash follow the picture. jumper-0=1 means just that. add a loop of solder into the holes of jumper 0.

The Hotspot Module works as expected and advertised. The parts needed to fit it in various cases are included. Soldering the headers for use on a Raspberry Pi are covered in the instructions. Beyond that you will need to research how to configure it based on your end purpose.I paired mine with a Raspberry Pi 3B+ and a Nextion 3.5" screen in a custom plexiglass case. Any issues I had were due to configuring the software and are independent of the hardware.

This Duplex MMDVM Rf board is an earlier production date 06/2018. It must have been replaced by a correctly designed board dated 09/2018. I have 5 of those RF Duplex boards. All work as they should without issue. This board simply doesn't. It appears there was a design error that left off some connections going back to the Raspberry Pi computer that are used to send operating parameters of the duplex RF board to the computer. Without these connections providing necessary feedback to the computer operation is erratic at best and limits it's operation. It manifest the problem by the computer not being able to command the duplex RF board properly. Display feedback is missing or erroneously display if at all when using a large display screen. In testing I replace a known correctly working duplex RF board in two different units and had them both fail to operate as they should. I do not in any way recommend this item.

I use this with my AnyTone at home. I put a bigger antenna and it covers most of my property. Setup is not exactly point and click, but not terrible.

Nicely built product but the firmware update instruction sent are different than the note listed on Amazon. The JP1 jumper settings along with the boot comments are poorly documented and therefore mine does not work properly. I'm hoping a forum exists somewhere to better guide me.

Perfect fit on Raspberry Pi 3B+. I don't have a case yet. I just set it in top of the 3B+ case and use the phone instead of a screen. I was up and running in no time. Almost no loss. No need to figure an offset as it was zero. The only setting I had to adjust was to increase the gain/volume. Definitely recommend for Homebrew.

Using this on a Pi 3B+ running Pi-Star. Connecting using my Icom ID-5100A. Everything works as it should. No complaints. Was able to update firmware as well. Will purchase again.