UDRX-440

NW APRS Summer Gathering 2017

NW Digital Radio team members will be presenting at The Northwest APRS Summer Gathering in North Bend (WA) on September 9th.

Topics to be presented will include:

  • UDRX™ Status Update
  • A Raspberry Pi Based ~1W Transceiver mentioned at the Dayton Hamvention® (Xenia)
  • NetTNC an EMCOMM Appliance
  • UDR-Tracker an APRS® Mobile Appliance
  • ThumbDV™ New SW and Applications

To learn more about the APRS® event, subscribe  to the newsletter.

Presentations will be posted on the web after the gathering.

Note: NW Digital Radio team members will not be presenting at TAPR DCC in St. Louis this year.

UDRX – Status Report

Just back from Orlando Hamcation. Nice to meet many of our existing customers and chat with some new ones.

The UDRX made it thru initial bring-up and I drove them to Oregon, while Portland was being slammed with snow. Jeremy has completed the updated Drivers and PLD code and shipped the first unit to Dennis for IQ audio and RF path analysis.

No significant problems were found at this stage.

I’ll be  working on the PA and RX/TX switch while Dennis fine tunes the IQ/RF.

I’ve also been working with CMs and it looks like we’ll be be able to meet our production cost goals at this point. There is still ambiguity on the Heat Sink Extrusion and enclosure cost.

I’ll post approximately monthly as we continue to make progress.

Bryan K7UDR

UDRX Pilot Boards have Arrived

After dealing with component shortages and Holiday schedule, the UDRX pilot boards arrived this afternoon from our assembly house in Renton WA.

The boards now go into the lab for initial bring-up, then they will be split into 3 task groups:

  • SW Driver additions and updates
  • IQ audio and RF path
  • PA and RX/TX switch

There are a substantial number of relatively minor changes to the design, in addition to the major change in form factor to accommodate the switch to the R-Pi 3.

I will provide an update on our progress by Hamcation in Orlando next month, where the pilot units will be on display. There is still significant work ahead, before we can determine if the pilot run can move to production.

Thanks for your patience and support,
Bryan K7UDR

UDRX Assembled PCB

UDRX with Pi and PA

UDRC: The Linux in the Ham Shack Interview

The good folks at the Linux in the Ham Shack podcast interviewed John (K7VE) about the UDRC and other topics.

The segment starts at minute 16:30 of podcast #166

A Short UDRX and UDRC Update from MicroHAMS 2016

UDRX does Raspberry Pi 2

We have moved from our custom linux SBC to the Raspberry Pi 2. This has a number of advantages:

  • Higher Performance
  • Lower Cost
  • Better Software Support
  • Easier for Developers to migrate SW to the UDRX
  • Future processor migration path, assuming header pinout compatibility

Of course nothing comes for free and there has been additional SW work migrating from a 3.x to 4.x kernel. Packaging has also been affected, but the overall package is simpler and better for final assembly. We are testing now using our existing RF Deck and a 40 pin adapter cable.

Existing SBC

Existing SBC

 

SBC VS R Pi 2

SBC VS R Pi 2

 

40 Pin Remapping Header

40 Pin Remapping Header

 

Test Configuration with Optional Paper Clip

Test Configuration

We are engaging with a Contract Manufacturer for Turn-Key Production, including custom extrusions. Engineering is moving forward towards a pilot run, once the Pi2+RF Deck is qualified at full power.

Expect the next update in January

MicroHAMS UDRX-440 Update

UDRX Update

Dayton Hamvention 2015
Dennis recently completed the Software Defined Receiver for the UDRX-440.  It now goes to Basil for integration with our framework.

This is a complete general purpose software defined receiver with a socket interface to support multiple protocols.   AGC is implemented in hardware as there is no conventional FM limiter which would prevent us from implementing other modulations. The MSK receiver utilizes dual software PLLs to implement Mark and Space separately allowing us to track not only carrier error but frequency shift as well. Lock times for a 100Hz frequency error are on the order of 15 mSec or about one and a half characters at 9600, reducing training time for TX/RX switching. There is a separate debug socket for reporting modem state suitable for advanced diagnostics. The fixed point DSP receiver uses less than 10% of available CPU cycles.

When combined with the previously implemented software designed transmitter, we now have a complete SDR transceiver.

The transmitter PA is now running at full power and initial thermal evaluation shows that we have met our goal of 100% duty cycle in a 20C shack without a fan. A separate temp-controlled fan kit will be available for high ambient temperature, continuous duty applications. Spurious emissions are less than -60 dBc.

These are the last significant milestones for the UDRX. Once integration and characterization are complete we will move the UDRX into Pilot Production on the full manufacturing line for field testing.

If you are at Hamvention, please come by our booth (EH0515) and visit with Bryan and John — we are thrilled to have reached this point.