Archives for

Huntsville Hamfest

We won’t have a booth at Huntsville this year, but John Hays (K7VE) will be speaking at the D-STAR Innovations Forum on August 15th.

If you would like to visit with John be sure to catch him at the Huntsville Hamfest.

ThumbDV™ – Model A

Beginning with orders placed after July 9th, 2015 a new revision of the ThumbDV™ will be shipped.

The only difference between the original ThumbDV™ and the new model ‘A’ is that the USB serial port will now operate at 460800 baud instead of 230400 baud.  Programs like WinDV, DummyRepeater, and AMBEserver have been updated  to support both baud rates.  It may take a few days for DummyRepeater to be pushed out with the change.

There is no change for D-STAR applications except selecting the faster baud rate.

Note: At this time we recommend using DummyRepeater with ‘AMBEserver -n’ (-n is for new baud rate) for best performance with model ‘A’.

The latest source for AMBEserver can be found at GitHub.

Why are we changing the baud rate?

NW Digital Radio has been working with some OEM customers who will be integrating the ThumbDV™ into their products, including DMR based systems, and their existing programs use the higher baud rate to communicate with the AMBE3000 chip.  Moving to the higher rate allows these customers to more quickly integrate these systems.

Will older ThumbDV™ devices continue to be supported and sold?

NW Digital Radio will support ThumbDV™ both original and ‘A’ models.

Our inventory of original ThumbDV™ dongles sold out on the same day that the new model ‘A’ was delivered from the Washington State assembly house.  We do not plan to manufacture any additional 230400 baud ‘original’ ThumbDV™ dongles.

All new orders will receive the ThumbDV™ model ‘A’

What about the PiDV™ (DV3000)?

There are no plans to move the PiDV™ (GPIO) to a different baud rate.  However, it is relatively easy for the user to modify the boards to support additional baud rates through trace cutting and jumpers. [Note: the PiDV™ is not currently being produced or sold. Please use the ThumbDV™.  If you need a large quantity of PiDV™, 50 or more, contact sales.]

There has been some confusion, hopefully the following will help clear it up.

The ability to do vocoding for DMR, D-STAR, Fusion, P25 Phase 2, etc. is built into the AMBE 3000 chip.  The new Model ‘A’ only changes the baud rate that the serial port passes packets to and from the chip.  It does not change any other capability between the original and Model ‘A’.

The 230400 baud rate is sufficient for all of these protocols.  The OEM(s) we are working with are swapping out another USB AMBE-3000 device with the ThumbDV. That other device was strapped at 460800 and they just want to swap it out.

It doesn’t make sense for us to make 2 models, one strapped at 230400 and one strapped at 460800 so we are now making all units strapped at the higher baud rate.

There is no secret, hidden, message here.  It’s a simple baud rate change that we wanted customers to be aware of, nothing more.

Here is the math:

The fastest input from one voice stream is 128 Kbps (8000 samples per second at 16 bits). So 230 kbps in is more than sufficient. The fastest rate out is full rate at 7.2kbps, DMR, Fusion half rate,  and D-STAR are at 3.6kbps. (This is for encoding, reverse for decoding.) There is only one packet stream, so you don’t get any doubling of these numbers.

There is literally nothing different than the selected baud rate, implemented in an update printed circuit board that changes what lines are strapped down.

The AMBE 3000 chip provides the vocoding, and only the vocoding.  The various protocols embed the vocoding in their respective data streams.  The ‘devices’ (e.g. AMBE 3000 boards, dongles, etc.) are not involved in the actual protocols, only in turning voice into AMBE and AMBE into voice.

Please view John Speaks on DV Modes at MicroHams to see how digital voice systems are built up.

John Speaks on DV Modes at MicroHams

MicroHAMS UDRX-440 Update

Introducing the UDRC

Universal Digital Radio Controller
–UPDATED–

Here at NW Digital Radio we are always looking at ways to enhance digital communications for the radio amateur. As we have been marching forward with the development of the UDRX-440 there have been a few products that have come to market both from us and from other manufacturers.

When designing the UDRX-440 we wanted to enable D-STAR voice communications and designed a daughter card to provide the AMBE vocoder. We choose the DVSI AMBE-3000™ chip which has the potential of providing superior voice reproduction on D-STAR, but also supports AMBE+2 which is used by other radio standards such as DMR, NXDN, Yaesu Fusion, APCO P25 Phase 2, … We created the DV3000, which is available as a standalone product along with the open source AMBEServer to make AMBE vocoding available over a network. This Raspberry Pi shield rapidly gained a following and hundreds are now deployed around the world. Later, we created a USB connected version of this device called the ThumbDV™, which has opened up AMBE vocoding to hundreds of additional users.

When Yaesu offered their new DR-1X Fusion repeater to clubs for $500  (updated information), the Northwest Digital Radio Club (not part of NW Digital Radio company) purchased one and put it on the air in Edmonds, WA as NW7DR.  The half rate digital voice is very good and the full rate voice is excellent. It wasn’t long before John (K7VE) looked at the external accessory adapter and wondered if the repeater could also do D-STAR. After considerable research and experimentation using a Raspberry Pi B+/2 for control and a DVRPTR V1 GMSK modem it was discovered that the DR-1X made an excellent D-STAR repeater. By comparison, John’s Kenwood based repeaters often run significant BER (bit error rate) on receive, at one location the Kenwood runs around 7+% BER, while the DR-1X is at 0%. (The repeaters are co-located and both use the DVRPTR V1.)

At first, the experiments ran into a known lockup condition when using an external controller in combination with Yaesu Fusion Digital mode. With the latest generation firmware the DR-1X is able to provide D-STAR, Analog, and Fusion Digital all on the same channel on a per transmission switched mode.  Mode control is accomplished using GPIO pins on the Raspberry Pi.

NW Digital Radio looked at the Raspberry Pi control system and soon decided that a combination control board with integrated CODEC could be built as a hat for 40 PIN GPIO headers on the Raspberry Pi and thus is born the Universal Digital Radio Controller or UDRC.

With the addition of the UDRC, the DR-1X will operate in these configurations. (WIRES-X requires a Yaesu HRI-200 attached to an external radio)

  • With the latest 1.00 family of firmware on the DR-1X
    • D-STAR/Analog
  • With the latest 1.10 family (after December 2015) on the DR-1X
    • D-STAR/Analog
    • D-STAR/Digital Fusion
    • D-STAR/Digital Fusion/Analog

The UDRC does not transcode between D-STAR and Fusion, it allows the DR-1X to repeat D-STAR transmissions and use the ircDDBGateway to communicate with stations, linked reflectors and repeaters, STARnet Digital Groups, etc.  Analog, Digital Fusion, and D-STAR are switched at the repeater on a per transmission basis.

The UDRC is designed as a simple to install addition to the DR-1X, however, NW Digital Radio has kept the experimenter in mind by providing various headers to allow straightforward hardware modification for integration with other hardware and applications. The built-in CODEC also will be available via a amateur packet radio standard mini DIN-6 port for software developers to adapt other modes, e.g. Packet Radio, VOIP (Asterisk/IRLP/Echolink), Codec-2, … Additionally, all GPIO and audio pins are available as solder through pads.

Share your application ideas on the UDRC group.

Estimated price for the UDRC is $89.95

 

DMR / D-STAR Gateway

The Germans have done it again!

From the folks that brought us the ircDDB network, we hear from Hans-Jürgen Barthen, DL5DI, that there is now a gateway between D-STAR (DCS Gateways) and Hytera DMR Repeaters using the AMBEServer with either the PiDV™ or ThumbDV™.  This gateway is in use at a handful of DMR repeaters in Germany and Austria with systems soon to be implemented in Sweden and Switzerland.

You can download executables for the gateway and combine with the AMBEServer to create your own gateway. The software does D-STAR callsign to DMR radio ID mapping and transports audio between networks using the Hytera API.

Another step toward Universal Digital Radio from the community of amateur radio developers using products from NW Digital Radio.

 

ThumbDV™: AmateurLogic.TV Episode 77

Tommy Martin, N5ZNO, shares his experience with the ThumbDV™ on Episode 77

 

 

ThumbDV™: Budd Churchward, WB7FHC Video

Budd updates us on his experience setting up the ThumbDV™ under Windows using Node DV (WinDV) from DUTCH*Star.

Also, there is an updated setup guide from the folks at AmateurLogic.tv

ThumbDV™ vs PiDV™

We have received a few inquiries about the functional difference between the DV3000 and ThumbDV™.

The ThumbDV™ is a thumb or dongle type DV (digital voice) device for connection to a computer (PC, Laptop, Tablet, Raspberry Pi, Odroid, etc.) to provide access to AMBE encoding and decoding.  It is the more portable of the two devices in that you can plug it into any USB (2.0 or greater) port on a computer and access it as a serial port via appropriate software to get into the D-STAR system.

AMBE USB 3000 ThumbDV™

ThumbDV™

The PiDV™ is designed to use the GPIO UART pins on a Raspberry Pi (including Raspberry Pi 2 and compatible devices such as the Odroid C1)  to provide access to AMBE encoding and decoding.  It can be adapted to other similar devices using jumper wires to connect the UART, but only maps to Raspberry Pi GPIO pins.

PiDV™

PiDV™

From a software point of view they are equivalent and are accessed as serial ports (COMx under Windows,  tty? under Linux/Mac OS X, UDRx) at 230.4 kbps.  Software for using these devices includes G4KLX’s DummyRepeater,  DUTCH*Star’s Node DV (WinDV), and modified versions of DSD (developers have modified for use with the ThumbDV™/PiDV™ for monitoring DMR, Fusion, P25 Phase 2, etc. — contact the developers for more information).

Visit the resource page for additional information.

 

Budd Churchward, WB7FHC, explains the PiDV™ on Raspberry Pi