Satoshi, 7M3TJZ/AD6GZ's D-Star Node and DV Adapter

Satoshi Yasuda, 7M3TJZ/AD6GZ, has two different constructions projects available. The one that is the main focus of this yahoo group - the node adapter - is basically a GMSK smart modem tailored to D-STAR.

The node adapter has two modes - simplex and repeater. In simplex mode, node adapter only serves to decode/encode the GMSK modulation used by D-STAR radios and turn it into a bit stream that can be fed into a computer. In repeater mode, the node adapter serves as a bit regenerative repeater. However, while in repeater mode, the node adapter does not have the capability to pass any data in/out of the computer. So, in repeater mode, the node adapter can not be linked to any D-STAR gateways/reflectors. This node adapter has no provisions to convert D-Star Digital Voice To Analog Voice. This hardware software combination operates in 100% digital mode.

He began by looking into the UT-118 works. It is entirely of his own design. Mr. Yasuda is/was a member of the D-Star standardization committee.

The main component is the CMX589A GMSK modem chip. The same chip used in many
of the Icom radios.

Probably the next most important chip is the 18F2550 PIC that runs his firmware.
This takes care of formatting/ recognizing the actual D-Star protocol, USB
communications etc.


More information can be found on Satoshi's web site.

Mark, KB9KHM uses his node adaptor in simplex mode with his D-STAR Hot Spot software that Mark wrote to provide a simplex RF point of presence to the D-STAR network. (He uses his D-Star HT with the adaptor hooked to an analog radio's packet port to pass D-Star digitally to a gateway server over the internet.)

In this video, Erik Finskas OH2LAK, of Finland shows his D-Star Hot Spot / node adaptor while holding a QSO:

And here is a slide-show overview of the GMSK Node Adapter:


In a later revision of Mark's hotspot software he added a routine that provides a way around the combination problem repeater mode and linking. Now you only need one pic, as the data received can be sent back out like a loopback, while still keeping a data stream to external D-Plus gateways.

---

His AMBE DV adaptor on the other hand is a full blown adapter to turn an analog radio in to a D-STAR radio and does include provisions to encode/decode AMBE.

In this video Peter, DJ6ZR/AI4UE and Don, WD4CWE test D-Star on 6 meter and 10m with the Satoshi DV Adapter. With more info at http://dstarradioclub-international.com/default.aspx



Mark, G7LTT/NI2O also has had 10 and 6 Meter successful D-Star QSO's using Satoshi's AMBE DV adapters interfaced to two Yaesu FT-8900 quad band FM rigs.

Satoshi's AMBE DV adapter does decode and encode raw D-Star tailored GMSK unlike the the DV Dongle that Moe, AE4JY and Robin, AA4RC have in production.

Satoshi's does seem better suited for the D-Star to SIP translation project that is being investigated.

70 CM HSMM?

What you are looking at is Ubiquiti's 2.4 GHz bullet. It's their simplest, and cheapest ($40) 802.11 device. It's basically a ethernet->N converter. Now imagine if it was capable of 420-450 MHz.  (Realistically something for this band would likely first start off in a mini-PCI configuration.)

Ubiquiti products are based on the Atheros chipset which allows you to reduce your channel width with to 5 MHz. This would fit in the lower 12 MHz of the band where ATV is allowed, and can still yield up to a 10 Mbps signaling rate. That kind of throughput can support live video feeds from IP cameras, Asterisk / IP telephony, and just about anything you can dream up.

When WiMAX platforms for operation around 3 GHz were in their planning stage, Ubiquiti acted quickly to provide a 3 GHz 802.11 solution for direct competition. That worked out well for us hams, as there is a 3 GHz ham allocation.    

WiMAX is much like ordinary Wifi except it uses licensed spectrum. Its for last mile connectivity, and the potential of mobile operations. Verizon wireless broadband is probably the most best example that most might be familiar with.
There are certified WiMAX platforms emerging for operation between 400-1000 MHz, covering the 70 and 33 cm bands, with selectable channel widths from 1.5 MHZ to 7 MHz. So a 400 MHz capable product from Ubiquiti or someone else doesn't seem that far fetched. 

If you have experimented on 2.4 GHz, you know how frustrating it can be trying to combat the high noise floor and plethora of Part 15 devices. When you utilize the channels unshared with Part 15, you still at best, are limited by the line of site propagation of those microwave bands. HSMM experimenters are usually few and far between so an organized approach to commercial tower sites is likely not the case. This is what would make a 420-450 MHz capable device ideal.

If the idea of 70 cm HSMM appeals to you, I encourage you to vocalize your interest. (Section managers and Ubiquiti sales seem like logical places to start :)

{Edit 4/11/10}
http://www.xagyl.com/store/product.php?productid=16450&cat=0&page=1

XAGYL FLR4G30 450MHz 1000mW miniPCI

A compatible IRLP Interface Schematic

IRLP nodes generally must use official IRLP boards. Their reasoning is that headaches the IRLP volunteers would have to deal due to nodes using self-built cards that weren't behaving properly. It appears impossible to obtain an IRLP node number without an order form and payment. http://www.irlp.net/orderform.html The IRLP board is $105. They also suggest a $40 donation.

However maybe you are interested in messing with a Linux based repeater controller. Or are I need of a spare IRLP board for interim node setups and testing.

Kyle, K0KN has designed a schematic for people in these situations, to emulate the IRLP board. This is perfect for people in these situations, as seen here. Otherwise you might find some people willing to part with theirs on the IRLP mailing list.

The IRLP board has an on-board hardware MT8870 DTMF decoder. It feeds the decoded digits as a four bit word to the printer port on the PC. This helps to ensure you have dull duplex control at all times, no matter what the state of /dev/dsp.. The decoded digits hit the custom_decode file where you can script/define functions.

If you wish to use IRLP with a different open interface such as the VA3TO, WB2REM, G3VFP, G4CDY,...Rigblasters, MFJ, SignalLink, etc. (as many of these interfaces have schematics readily available.) The following two open projects have the code necessary to talk to interface IRLP to other hardware interfaces. The rtpdir bridge - to bridge EchoLink IRLP and Asterisk . And thelinkbox also supporting USB sound FOB interfaces.