Very well built board. Stable frequency with negligible packet loss when paired with the Pi-Zero WH. Recommend getting the high quality Diamond stubby antennas with it.

Some more documentation particularly around advantages of a duplex board for DMR, recommended accessories (Pi-Zero WH, power supply requirements, OLED screen and case) with screen shots of pi-star setup would help buyers choose this over the many cheaper MMDVM hotspots available.

73,
Venkat, K7VKT

Gunnar | March 25, 2019

Best Quality Hotspot

For MMDVM DUPLEX in Pi Zero Form Factor (Duplex )

Thank you for your shipment of 2 MMDVM DUPLEX Pi Zero Form Factor boards to Germany! Visually the Quality of the board is very good!
I have now to do some testing if your product has better HF separation between TX and RX and therefore has less desensitisation of the RX. Also have to have a look how the HF range is at all.
Mounting: I am using your board an an Raspberry 2B, and a RPI Header 40 Pin to rise the board a few millimetres higher so it also fits on top of the Pi2B.
Programming: I am using Pi-Star Image 4RC which works very good. CPU Temperature not above +41 deg centigrade. No extra cooling.
Shipping: need to add time if German Customs pics it. In my case it needed 1 week extra. Then I had to pay VAT, in Germany VAT = MwSt 19%. Customs did not charge any toll :-)
Kind regards an 73

Response from N5BOC Store ( LoneStar Semiconductor Designs ) | April 14, 2019

Gunnar,

Thanks so much for the kind words about the hotspot. I'm sorry you had so much trouble getting it through customs. I don't think there is anything I can do to facilitate that, but if there is please let me know so I can help future customers in Germany.

I too use it with a Pi3 when I am doing testing. I purchased a "stacking header" from Adafruit and with that it will clear the USB connectors.

I know by the time you paid VAT and shipping to Germany it made my board quite expensive. I really appreciate the support in spite of the extra cost to you.

Regards,
David

Kevin | March 22, 2019

I ask for information on a problem and was ignored

For MMDVM DUPLEX in Pi Zero Form Factor (Duplex )

Dennis claimed to not have the repeater not found issues that the Chinese duplex boards do on DMR but they do. I inquired on several Facebook groups he posts on about it he asked my bit error rate wich was .2 -.3%. His only response was well I don't have that problem with my radio. Im using a Motorola xpr7550 and a Anytone 878 both have the same problem.

Response from N5BOC Store ( LoneStar Semiconductor Designs ) | April 14, 2019

I have no idea about what the first issue you mention is. You speak like this "repeater not found" issue is a common thing everyone knows about. Never heard of it before you brought it up. So it would have been a bit hard for me to claim mine didn't have an issue with something I've never heard of. I have to say It doesn't sound like a hardware issue if it works on any TG at all.

Honestly a 0.2% BER is nothing. I don't understand why your concern and I challenge you to find a board that has a better BER. At that low of BER It does not impact your ability to communicate at all. You also specified some other issue and I believe my response was, " I don't have that issue with my radio so I can't investigate it if I can't reproduce the issue". Your review is omitting details that I feel make it misleading.

Jay | Feb. 26, 2019

Not sure if the Pi or the MMDVM is bad.

For MMDVM DUPLEX in Pi Zero Form Factor (Duplex )

Purchased a Pi-Zero from another source and the mmdvm from here. Got everything up and running for about 2 days now it doesn't. We have tried reflashing images to router configuration and nothing seems to work. We are still trying but it is looking more and more like I'm out of luck.

Response from N5BOC Store ( LoneStar Semiconductor Designs ) | April 14, 2019

Jay,
Did you contact me through Tindie?
I'd be glad to help you if you did.

Philip | June 24, 2018

So far meeting my expectations

For MMDVM_HS_HAT Rev 1.5 (SIMPLEX )

The top hat is Working well with my Fusion Radio. Many more modes to try out. I am looking forward to getting my DMR Radio working.

Response from N5BOC Store ( LoneStar Semiconductor Designs ) | July 11, 2018

I'm glad to hear it is working well for you Philip! I look forward to seeing you on DMR.

William | May 12, 2018

Great MMDVM Hotspot for DMR/C4FM/D-Star

For MMDVM_HS_HAT Rev 1.5 (SIMPLEX )

Have a genuine ZUMspot and needed a 2nd one. Chose this one from N5BOC and it works just fine. He provided the receiver offset which made it easier to get on the air quickly. Great product, recommended! Dave, K6WDE

Response from N5BOC Store ( LoneStar Semiconductor Designs ) | May 22, 2018

Dave,
I'm really happy to hear this made it easy for you to get on the air. And I'm glad you're enjoying the board.

73's
David