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Reports from Dayton are that Kenwood has a D-STAR tri-band handheld under glass in the booth, along with colorful brochures. None of my sources are reporting on price or availability, and the documents all show “Tentative”. Never the less, this news along with the development going on within the dv4 group are pretty exciting!

Kenwood APRS DStar ! @hamradio360 #hv2016live #dstar @kenwoodhamradio pic.twitter.com/vLNrdATtb4

— KF7IJZ (@KF7IJZ) May 20, 2016

UPDATE: Tom KJ9P on the ground in Dayton reports that the model name and number haven’t been published yet, but it should be available by year end with an MSRP between $500 and $700.

I also had a D-STAR conversation with Tony N8NNX as he was walking the floor at Hamvention regarding the dv4mobile product. His inquires came back also with a 2016 availability date and prices between $800 and $1000.

Michael Brown, KG9DW, is a regular contributor to AmateurRadio.com and writes from Illinois, USA. Contact him at [email protected].

Reports from Dayton are that Kenwood has a D-STAR tri-band handheld under glass in the booth, along with colorful brochures. None of my sources are reporting on price or availability, and the documents all show “Tentative”. Never the less, this news along with the development going on within the dv4 group are pretty exciting!

Kenwood APRS DStar ! @hamradio360 #hv2016live #dstar @kenwoodhamradio pic.twitter.com/vLNrdATtb4

— KF7IJZ (@KF7IJZ) May 20, 2016

UPDATE: Tom KJ9P on the ground in Dayton reports that the model name and number haven’t been published yet, but it should be available by year end with an MSRP between $500 and $700.

I also had a D-STAR conversation with Tony N8NNX as he was walking the floor at Hamvention regarding the dv4mobile product. His inquires came back also with a 2016 availability date and prices between $800 and $1000.

Michael Brown, KG9DW, is a regular contributor to AmateurRadio.com and writes from Illinois, USA. Contact him at [email protected].

The 288 km path  courtesy: REAST

One of the local lightwave builders, Mark (VA7MM), brought my attention to some outstanding lightwave work conducted several years ago, by a group of very dedicated amateurs in Tasmania.

A pair of articles describes their successful attempts to send signals, via cloudbounce, over the astounding distance of 288km (180mi), crossing Bass Strait between the north Tasmanian coast and southern Australia.


What did it take to transmit lightwave signals over such a distance? Basically a system similar to the ones recently employed in our own local lightwave experiments but on a grander scale ... much grander!

The receiver is based on one of the KA7OEI designs, with modifications to increase its sensitivity. The receiver, and several other designs, can be found on Clint's website here, probably the best source of information on amateur lightwave available anywhere.

The lightwave receiver  courtesy: REAST

Although the basic receiver used a typical-sized fresnel lens, what really set it apart from most was the use of a large (10mm x 10mm) Avalanche Photo Diode (APD) for the detector, to maximize the field of view produced by the fresnel and gather every bit of light possible ... at a cost of $1200!

The 10mm x 10mm rx APD courtesy: Hamamatsu

The transmitter was also big, consisting of an array of 60 red Luxeon III LED's, similar to the Red Rebel Luxeons used in our own local tests. Each LED had its own 12cm square fresnel lens, heatsink and method of focusing. Certainly this was a mammoth project, by amateur lightwave standards.

The 60 LED TX array courtesy: REAST

One of the biggest problems when using such a high-gain system, is the difficulty in pointing. They found that aiming in altitude was simply a matter of pointing a few degrees above the horizon but azimuth pointing was much more critical, requiring accuracy to within a half-degree.

Earlier long-haul tests out to 209 km used the digital JT65 mode for signal decodes but the 288 km test used a fairly esoteric weak signal mode called WSC built on the Spectrum Lab software. This mode is capable of digging almost 20 db deeper into the noise than JT65, down to almost -50db.

An in depth description of the two long-haul events, including equipment schematics, can be found in "288 km Cloudbounce from Tasmania to the Australian Mainland" and in "209 km with Narrow Beamwidth Transmitter".

The 288 km crossing project evolved over several years and is all very well documented, from the first early steps, at the Radio and Electronics Association of Southern Tasmania's (REAST) website here.

This adventuresome project was largely the work of VK7MO, VK7JG, VK3HZ and VK7TW. Their work is most inspiring and much can be learned from seeing what they discovered when transmitting into the cloudy nighttime skies.

Such an endeavour as this makes the local, much shorter Georgia Strait crossing, seem like a cake-walk, but I can't imagine using anything that big and bright here without causing trouble ... it would probably appear much too 'laser-like' to talk one's way out of a jam. Pointing anything resembling a laser light into the air these days is simply begging for trouble.

I can however, envision a scaled-down version, perhaps consisting of an array of four Luxeons ... at least on my end of the path, but even pointing one of those from the city could be problematic. Perhaps any NLOS lightwave attempts across Georgia Strait will need to be well away from Vancouver and its two-million sets of eyes.
Steve McDonald, VE7SL, is a regular contributor to AmateurRadio.com and writes from British Columbia, Canada. Contact him at [email protected].

During my working life I collaborate with a large groups on multiple sites and we do stuff together. When I am attempting a radio projects I take on a different tack. I attempt to be either an expert in many things or I follow sets of instructions slavishly. Most of the time it takes a long time and there are numerous failures or dead ends along the way. I’m not sure why I do this.

There are many websites that will offer support to the frustrated builder or keen expert. But few that offer hobby collaboration (or at least I haven’t looked too hard but a quick trawl didn’t really yield much). I wonder why that is? A probably misquoted quote goes along the lines of ‘Travel alone, travel fast. Travel together, travel further’. You could argue that sites such as forums offer support and collaboration by using a project management analogy, I can not agree with that. Tasks are not identified, resources are not defined and task durations are not agreed. Expertise is sought, sometimes this results in no responses.

A local ham was at the centre of a project that has now become a major SDR rig. He worked from home, in the evenings with a group spread around the world. They have developed a really astounding product that is now sold as part of the Apache Labs brand. Why is this approach not prevalent?

I’m not offering a solution, just a question. Does a place exist or am I right in assuming that there are some international superstars that produce lots of ‘things’ from 3D designs through to circuit boards and kits that hobbyists use? I think there ought to be a place where we can go to collaborate. I just don’t know where it is or how to engage with it….yet.

Alex Hill, G7KSE, is a regular contributor to AmateurRadio.com and writes from Cumbria, UK. Contact him at [email protected].

While I’m not at Dayton, I have been able to follow some of the announcements. Here’s a quick list of  the interesting ones so far!

The Elecraft KX2 – a smaller version of the KX3, 80 through 10m and fits in your hand, $750!

The DV4Home and D4Mobile radios – built from the DV4mini adapters, but full function radios. No prices or availability yet, but a great concept. I’ll be interested in the reports from the show floor.

I’m not expecting anything big from Icom. Yaesu might announce something in an HF QRP rig, but I’m not that interested (I think they are still covered up trying to get Fusion/WIRES-X going like they want). I would think Flex will have something new to show, and there is still the nagging rumor that Kenwood will do something with a D-STAR radio. Even if you don’t make the trek to Dayton, you can certainly find out a lot with a few Google searches or watching the Twitter feed!

#hamvention Tweets

Michael Brown, KG9DW, is a regular contributor to AmateurRadio.com and writes from Illinois, USA. Contact him at [email protected].

While I’m not at Dayton, I have been able to follow some of the announcements. Here’s a quick list of  the interesting ones so far!

The Elecraft KX2 – a smaller version of the KX3, 80 through 10m and fits in your hand, $750!

The DV4Home and D4Mobile radios – built from the DV4mini adapters, but full function radios. No prices or availability yet, but a great concept. I’ll be interested in the reports from the show floor.

I’m not expecting anything big from Icom. Yaesu might announce something in an HF QRP rig, but I’m not that interested (I think they are still covered up trying to get Fusion/WIRES-X going like they want). I would think Flex will have something new to show, and there is still the nagging rumor that Kenwood will do something with a D-STAR radio. Even if you don’t make the trek to Dayton, you can certainly find out a lot with a few Google searches or watching the Twitter feed!

#hamvention Tweets

Michael Brown, KG9DW, is a regular contributor to AmateurRadio.com and writes from Illinois, USA. Contact him at [email protected].