Interesting and Advanced Projects / Products in Amateur Radio

Last updated 2021-06-24.

Update 2021-06-19. This list isn't meant to be a semi-static list. It's a gathering place for what I've found to be interesting in Amateur Radio that I chose to make public. Eventually each of these entries will be written about in detail.

Amateur Radio Bands of Interest

I've mostly been a fan of the Amateur Radio Very High Frequency (VHF) and Ultra High Frequency (UHF) bands, rather than the Amateur Radio High Frequency and Microwave (above 1 GHz) bands. Being in the US, I'm subject to, and benefit from, the allocations of Amateur Radio bands from the Federal Communications Commission (FCC). Other countries' Amateur Radio allocations are different. The American Radio Relay League (ARRL) has a nice page with US Amateur Radio allocations in text rather than hard-to-read poster form. The bands of most interest to me, and why. Links are to the relevant Wikipedia articles:

• 28.00 - 29.70 MHz (10 meter band) - This band is underutilized by most Amateur Radio operators, but reasonable speed data. It offers some interesting propagation randomness, especially in the summer.
• 50.00 - 54.00 MHz (6 meter band) - Like the 10 meter band, this band is underutilized and can do data, and offers interesting propagation randomness.
• 144.00 - 148.00 MHz (2 meter band) - The 2 meter band is the most popular VHF / UHF band. If offers good range (within Line of Sight Limitations). It was the most commonly used band for packet radio - 145.01 MHz was the original packet radio frequency, and 144.39 is used very extensively for Automatic Packet Reporting System (APRS). 
• 219.00 - 220.00 MHz (1.25 meter band) - The 219-220 MHz band was allocated to secondary Amateur Radio usage when 220-222 MHz was reallocated. Its arcane usage rules means that it's never been used (to my knowlege) and there's no activity (to my knowlege) to change that status.
• 222.00 - 225.00 MHz (1.25 meter band) - The 222-225 MHz band in the US is underused. It's an ideal "playground" for data communications, but is hampered by few 222-225 MHz radios currently in production (see below).
• 420.00 - 450.00 MHz (70 centimeter band) - Most of the US is blessed with 30 MHz of spectrum in the 70 centimeter band. Those of us unfortunate enough to live within approximately 75 miles of the Canada / US border (Line A) cannot use 420.00 - 430.00 MHz as that portion is allocated to commercial use in Canada. The 70 centimeter band is used extensively for higher speed / higher bandwidth communications. For example, it's acceptable in the FCC rules to use a 100 kHz channel within the 70 centimeter band.
• 902.00 - 928.00 MHz (33 centimeter band) -  The 33 centimeter band is one of the most interesting US Amateur Radio bands. It overlaps 100% with the Industrial, Scientific, and Medical (ISM) rules, meaning that there's no "exclusive" Amateur Radio operation in this band. There are licensed services within 902 - 928 MHz but those licensed services cannot require the license-exempt (ISM) users to cease and desist, and must accept any interference from licens-exempt users. In my opinion, 902-928 MHz is most useful from technologically sophisticated ISM devices such as those from Freewave Technologies and other vendors.
• 1240-1300 MHz (23 centimeter band) - The 1240-1300 MHz band in the US is underused. It's an ideal "playground" for wideband data communications, but is hampered by only one Amateur Radio available for this band.

Of all the bands above, the 1.25 meter band 70 centimeter bands are of the most interest and utility to me. It's still possible to obtain a repeater allocation for those bands in Western Washington. In Western Washington, the 2 meter band is considered to be "full up - don't bother asking" by the Western Washington Amateur Relay Association (WWARA) despite the near total silence of the vast majority of repeaters on 2 meters.

Websites Doing Interesting and Useful Things
Some of these have a hardware or software component, but are included here because there's an additional element of organization beyond just their software or hardware.

Note - Organizations and Conferences that allow some level of user involvement (social) were spun out of this page into a separate page - Interesting Amateur Radio Groups / Clubs / Informal Associations / Meetups / Online.

• 44net - Static IPv4 addresses (and routing) are available for Amateur Radio experimentation.
• aprs.fi - aprs.fi is the "public face" of Amateur Radio APRS activities. For example, world-circling balloons carring Amateur Radio beacons can be followed by anyone, including school kids. aprs.fi is just an amazing project.
• Amateur Radio Engineering Task Force (ARETF) - Think RFC's for Amateur Radio. It didn't quite launch, but it has potential to be revived is being revived with a different focus.
• Amateur Radio Internet Exchange (ARIX) - An educational and research network used to connect ham radio operators by providing licensed Amateur Radio enthusiasts a free fabric to inter-connect experimental IP networks.
• Amateur Radio Software Awards - This is needed - kudos to the ARSA Award Committee. 
• Brandmeister - Brandmeister is the worldwide "backbone" for Digital Mobile Radio (DMR) repeaters used in Amateur Radio. What's laudable about Brandmeister is that they're open to experimentation and evolution of DMR usage such as position reports (like APRS), data, and other experimentation. Other DMR networks, including two here in the Pacific Northwest, are run essentially as commercial networks - no experimentation, only certain types of conversations allowed, and much "regimentation". Anything I'm directly involved with in DMR will use Brandmeister.
• Broadcastify - The world's largest source of public safety, aircraft, rail, and marine radio live audio streams. It's a good example of what can be done.
• Decentralized Amateur Paging Network (DAPNET) - Interesting project in Europe of using paging technology in Amateur Radio for message distribution.
• Hackaday.com - I love Hackaday because they treat Amateur Radio, especially data modes and projects (like New Packet Radio) as interesting wireless experimentation for techies. Hackaday makes Amateur Radio look cool to techies, which we desparately need more of.
• HamWAN - HamWAN is a vision for building an Amateur Radio Wireless Internet Service Provider. It began as a project in the Seattle area and has since been replicated in other areas.
• Highspeed Amateurradio Multimedia Network (HAMNET.EU) - A Europe-wide high speed wireless TCP/IP network for Amateur Rado. Best explained in a video presentation. 
• IRCDDB - IRCDDB is the "non-official" network of D-Star repeaters; anything I do with D-Star will use IRCDDB.
• Laurel Volunteer Examination Coordinator (VEC) - Taking your Amateur Radio examination with a Laural VEC team is a superior exprerience. They do not charge a fee for an Amateur Radio examination, and they upload the license application electronically so you have your callsign much faster than other VECs.
• Mac Ham Radio - Website for Amateur Radio Operators using Apple MacOS and Apple iOS software and devices.
• MicroHAMS Digital Conference - MicroHAMS is an Amateur Radio club based in Redmond, Washington, USA. What makes it special, in my opinion, is that it sponsors an excellent Digital Conference in the Spring, on par (in my opinion) with the ARRL and TAPR Digital Communications Conference (DCC).
• Open Research Institute (ORI) - ORI's genesis was developing a ground station system for a potential Geosychronous Earth Orbit (GEO) satellite payload that would have been accessible from the North America. The satellite didn't happen, but ORI continued and morphed into a more generalized organization.
• QRP International - I'm much more of a fan of QRP (weak signal) radios now that WSJT exists.
• RadioID.net - Digital Mobile Radio (DMR) wasn't designed for Amateur Radio with support for callsigns, only "ID numbers". For DMR to be usable in Amateur Radio, someone had to provide a "translation table" of DMR ID numbers to Amateur Radio callsigns, and RadioID.net took on that task and, in my experience, does it well.
• RadioReference.com - database of public safety frequencies and live audio feeds of public safety.
• Repeaterbook.com - In my opinion, Repeaterbook.com and its apps is the best director of Amateur Radio repeaters. Its data is crowdsourced and usage is free.
• Reverse Beacon Network - Hams are incredible creative; this is a network of receivers connected to the Internet. See where your signal is being heard around the world.
• Signal Identification Guide - an open sourced (Wiki) compendium of various modulation types. When you receive something you don't understand, look it up here.
• Signals Everywhere - Good reference site on using Software Defined Transceivers.
• SMSGTE - A gateway between Amateur Radio APRS messages and Short Message Service (SMS) messages.
• Weak Signal Propagation Reporter Network (WSPRNet) - Network of receivers that monitor for Weak Signal Joe Taylor - Experimentatal (WSJT-X) transmissions
• Winlink - Winlink has made "last mile emergency email" plug and play. Within their paragigms, it works well. I think every Amateur Radio operator should support Winlink for emergency communications.

Interesting Hardware / Projects - Software Defined Receivers and Transceivers

• Analog Devices ALADM-PLUTO - A friend directed me to this device for getting started with GNU Radio. This device is different because it's a software-defined transceiver, not just a receiver.
• CaribouLite SDR - A software defined transceiver for the Raspberry Pi Zero. Secondary Link.
• F5OEO rpitx - It doesn't get any cooler than a software defined transmitter that's just a Raspberry Pi with a wire connected to a GPIO.
• Flex Radio - I've been impressed with Flex Radio since their founding as they are "all in" on Software Definied Radio for Amateur Radio HF like Tesla is all in on electric drive vehicles. I just wish they did the same thing for VHF/UHF radios.
• Heathkit SB-104 Software Defined Radio - Dan Quigley N7HQ (now Flex Radio's Director of Amateur Products) did a very nice job retrofitting a Heathkit SB-104 with a TAPR High Performance Software Defined Radio (HPSDR) and other modules. Dan completely preserved the look, feel, and function of the SB-104. I attended the presentation that's linked.
• KiwiSDR - A software defined receiver designed specifically for the Beaglebone series of single board computers. The combination is specifically designed to be used as a web-based receiver, accessible locally or (preferred) accessible from the Internet.
• KrakenSDR - A phase-coherent software defined radio with five RTL-SDRs.
• LimeSDR - This is a capable software defined transceiver. What impressed me is that the manufacturer decided to do an Amateur Radio front end for it called LimeRFE - power amplifier, etc.
• Nuand Blade RF - The same friend that directed me to the ALADM-PLUTO stated that the next step up in performance per dollar for a software defined transceiver is the Blade RF series.
• Red Pitaya - This is the most capable software defined transceiver that I know of. It's so sophisticated and capable that it wasn't originally a platform for radio experimetation. As I understand the story it was created as a multifunction radio test set. As it's evolved, it seems to be the favorite Amateur Radio software defined transceiver of those who can write digital signal processing software.
• RTL-SDR.com - They make good quality inexpensive software defined receivers, and their website is the best "heads up" about anything in the software defined receiver / transceiver field.
• SDRPlay - This is my favorite manufacturer of software defined receivers. In my opinion their products are a good balance of receive performance and reasonable cost. They have very capable software for their products for Windows, and a plug and play image for a dedicated Raspberry Pi.
• Softrock Software Defined Radios - When they debuted in 2005, these neat little kits answered my longstanding question about how simple a radio you could make with modern computer hardware doing the "heavy lifting".

Interesting Hardware / Projects - General

• Alinco DR-235 MkIII 222 MHz Radio - A 222 MHz radio currently in production that has a "data" connection for flat audio, suitable for higher speed data communications such as VARA. I've seen some mentions that this radio has been discontinued by Alinco.
• Arrow TNC - A full fledged TNC with built-in Bluetooth Low Energy (BLE) connectivity and incorporating a 144 MHz (2 meter) radio. 
• BridgeCom Systems Systems BCM-220 - A 222 MHz radio currently in production that has a "data" connection for flat audio, suitable for higher speed data communications such as VARA.
• Crowd Supply - Acts as an incubator (similar to Kickstarter) for small projects and a storefont. They feature a fair number of RF projects / products.
• Inductive Twig HamShield: LoRa Edition - This is the only vendor / project that I'm aware of that attempts to make the very popular LoRa hardware into compatibility with Amateur Radio. I think LoRa has great potential in Amateur Radio, especially if it can be made into a mesh network. Update 2022-06-16 - Not only is Inductive Twig no longer in business, I had a bad experience trying to purchase from them during their "closeout" sale. Thus I cannot recommend them and removed the link to this product.
• Kenwood TM-V71A Radio - In my opinion, this is the best VHF / UHF radio for data communications available at this moment. It features the 6-pin MiniDIN standard "data" port for easy interfacing, 144 / 440 MHz, 5 / 25 / 50 watts transmit power, and its settings can be controlled via RS-232.
• M17 Project - Developing a new Digital Voice standard, and hardware, for Amateur Radio. They have some interesting sub-projects such as mvoice (Linux soundcard client for use on the M17 reflector system) and building your own M17 receiver.
• Masters Communications Digital Radio Adapter (DRA) series of audio interfaces. These devices, particularly the DRA-45 and DRA-50 have become the preferred audio interfaces for using VARA FM, primarily because they have additional audio amplification to drive some radios to full deviation. 
• Mobilinkd TNC3 - Folks I respect really like this TNC. It's built around DSP, can handle 9600 bps FSK, it's battery powered, and communicates via Bluetooth. I've read, but cannot find a link, that the TNC3 can be flashed with firmware for the M17 Project.
• "NanoVNA" - This came out of nowhere a few years ago - an inexpensive, handheld, open source Vector Network Analyzer. These are just amazing. It's a bit of a learning curve to understand how to use them, but they're very powerful. Update 2022-06-16 - I was contacted by a person who claimed to be a developer involved with "the real NanoVNA", claiming that the link I originally provided is to an unlicensed (? Open Source?) clone rather than to the "real NanoVNA". I'm not equipped to sort out which of the "NanoVNA" is more "real" than another, thus I removed the embedded link. If you're interested, do your own research and form your own conclusions.
  
• New Packet Radio - Packet Radio reimagined as higher speed and native TCP/IP. Good article 1 article 2 on New Packet Radio.
• Nexus DR-X - This is a project that's local to me for a capable, multipurpose digital interface, with great software support.
• NW Digital Radio DRAWS - The DRAWS is my favorite built-for-purpose sound card modem for Amateur Radio, mated with a Raspberry Pi. I was particularly impressed that it was engineered with higher speed modes in mind such as 9600 bps (and faster) FSK and has no bandwidth-damaging transformers.
• Packet Radio Users Group (PRUG) FX.25 KISS TNC - FX.25 to date has only been implemented in Dire Wolf software (needs a host like a Raspberry Pi and a sound card). An "appliance" like this could make FX.25 and Forward Error Correction more widely used.
• QRP Labs (various products) - These are fun kits, centered around low powered CW radios, but there are some versions that can be used with some data modes like WSPR.
• Raspberry Pi - The Raspberry Pi ecosystem of products, projects, support, and software, and of course the inexpensive price, to me makes it the preferred computer platform for Amateur Radio. For as little as $10, "just throw a computer at it".
• Receive Beamforming with an Array of Inexpensive Software Defined Receivers Article / Paper / Code
• SG Lab 20 Watt 2.4 GHz Amplifier - Amateur Radio Operators within the footprint of the Es’hail 2 / QO-100 geostationary satellite use 2.4 GHz as an uplink frequency, so they need a bit more than a few milliwatts of power to reach geostationary orbit, even using highly directional antennas.
• SG Lab 20 Watt 2.4 GHz Amplifier (low power input) - See above; this version is designed for the very low power output of Software Defined Transmitters.
• TCP/IP over LoRa Radios - LoRa radios are a "fertile area for future development".
• Terrestrial Amateur Packet Radio Network (TARPN) Nino-TNC - This is a new KISS TNC with a USB interface capable of 9600 bps and a new Forward Error Correction (FEC) protocol.
• TNCPi9k6 - This is a 9600 bps KISS TNC for a Raspberry Pi designed by John Wiseman G8BPQ, originally produced by Coastal Chipworks (which has ceased operations).
• Unsigned.io OpenModem TNC - What can I say... I'm a fan of TNCs, especially ones designed and produced in the 21st century. OpenModem has a unique capability of logging AX.25 packets to an SD card for later analysis. 
• Unsigned.io RNode LoRa Radio - Another LoRa Amateur Radio for experimentation with LoRa technology.

Interesting Software / Projects

• Amateur Radio Emergency Data Network (AREDN) - Flash selected Wi-Fi radios with AREDN firmware to create standalone mesh networks.
• Amateur Radio Instant Messaging (ARIM) - A text chat system for Amateur Radio.
• axmail - Amateur Radio to SMTP email gateway.
• Chattervox - An AX.25 packet radio chat protocol with support for digital signatures and binary compression. Like IRC over radio.
• DIGI_NED - I've been told this software, although no longer actively maintained, is one of, if not the, best software for operating a digipeater.
• Dire Wolf - software based Packet Radio. It's simply amazing how much better Dire Wolf works than hardware modems. I can't offer enough kudos to WB2OSZ for Dire Wolf.
• Dragon OS - A plug and play Linux image of just Software Defined Radio packages.
• HamPi - Amazing integration of much Amateur Radio software for the Raspberry Pi, already compiled into a plug-and-play image.
• F6FBB FBB - Very capable Packet Radio Bulletin Board System (BBS). Yes, BBS' are still useful.
• fldigi - A suite of software data modes. FSQ is particularly robust.
• FreeDV - Open source digital voice. FreeDV is very efficient, and despite describing it as being for Amateur Radio High Frequency (HF) operation, it's usable for much more than Amateur Radio, and much more than just HF operation. What I like about FreeDV is that it's just another data mode - that translates to voice. Although FreeDV is software, it has been implemented in a hardware modem for use with SSB radios.
• G8BPQ Software Suite - G8BPQ's suite of software is Packet Radio Networking - Bulletin Board Systems, Chat Bridges, and much more.
• GNU Radio - GR is open source software defined radio. GNU Radio Companion is a graphical interface that makes it possible to create software defined radios by dragging modules around in a into graphic layout. In addition to the software and support, they sponsor the GNU Radio Conference.
• JNOS - JNOS is the swiss army knife of Amateur Radio packet radio networking. It's a multi-mode router, including basic AX.25, Net/ROM, TCP/IP (including encapsulation), and BBS routing. Yep, it's still going after all these years.
• JS8Call - The one thing that the WSJT software suite doesn't have is a keyboard-to-keyboard chat mode. JS8Call is an independent project based on the WSJT technologies that implements a very robust chat mode.
• KL4YFD Sound Card Modes - Not only is he developing new modes, but he's sharing his source code. Of particular node are his OFDM modes that take advantage of "flat audio" input / output on data radios.
• Linpac - Amateur Radio AX.25 chat and PBBS program using Linux's AX.25 stack.
• multimon-ng - Good example of obscure projects for Amateur Radio. This one decodes various obscure data modes, including POCSAG (paging). Imagine the robustness of paging used in Amateur Radio now that we all have access to high resolution timebases and flexible data transmission modes.
• MultiPSK - Like multimon-ng, integrates a number of data modes.
• OpenRTX - Open source firmware enabling new capabilities for selected DMR portable radios.
• OpenWebRX - web based multiple user sotware defined receiver.
• OpenWRT - Open source firmware for routers and Wi-Fi access points. It's the basis for AREDN and many other interesting projects.
• Pi-Star - Multiple Digital Voice modes used in Amateur Radio, on a Raspberry Pi.
• PiGate - Imagine you're at a mass casualty shelter and people have phones that don't work on (saturated or down) cellular networks. PiGate is an appliance that combines a Wi-Fi access point, web server, form for sending email, and integration with Winlink, so that non-hams can send brief emails, via Winlink, under supervision of an Amateur Radio operator.
• PiSDR - Raspberry Pi image of a wide range of software defined receiver software for a variety of software defined receiver hardware.
• RadioMirror - Basically, streaming blocks of files, with a checksum. I wrote a blog post on RadioMirror that explains my vision.
• Robust Packet - A project is underway to revive the Robust Packet on-air protocol.
• SDRServer - Streaming data to multiple users from a software defined receiver device.
• SV2AGW Packet Engine - Software that operates as a packet radio TNC that can be connected to multiple applications.
• Universal Radio Hacker - A complete suite for wireless protocol investigation with native support for many software defined radios.
• UZ7HO software Packet-Radio TNC - UZ7HO was one of the first to offer TNC capabilities (mostly) in software.
• VARA-FM - Vara is a "clean sheet of paper" approach to high speed data over Amateur Radio. It offers impressive speed on VHF/UHF with improved reliability. One impressive feature is that it can be used effectively over ordinary voice repeaters, even if there's a CTCSS tone used for access.
• XASTIR - Open Source APRS do-everything software.
• XRPi - AX.25 / NetRom / TCP/IP router, intended mainly for use in packet switched data-over-radio networks by radio hobbyists. It's a port (or evolution of Xrouter, originally written for DOS.
• WSJT - Dr. Joe Taylor W1JT has revolutionized Amateur Radio data communications by creating entirely new communications methods using advanced digital signal processing made accessible to Amateur Radio operators.

Space / Satellites

• AMSAT-DL (Germany / Europe), AMSAT-NA (North America) / AMSAT-UK (UK) - Satellites built, operated, and used by Amateur Radio Operators.
• Amateur Radio on the International Space Station (ARISS) - ARISS supports the Amateur Radio equipment and activities on the International Space Station.
• Es’hail 2 / QO-100 - This is the coolest Amateur Radio "satellite" (actually, it's a hosted payload on a commercial satellite) currently operational. It's cool because it's geostationary above Europe, Africa, and Middle East. A few luckly Amateur Radio Operators at the far Eastern edge of Brazil can also work it.
• Earth - Moon - Earth Communications (EME) - AMSAT started a tradition of naming Amateur Satellites Oribiting Satellite Carrying Amateur Radio (OSCAR) follwed by a sequential numeric designator. The first AMSAT satellite was named OSCAR-1. EME enthusiasts sometimes refer to Luna as "OSCAR-0". I just think EME is uber-techie cool.
• FalconSAT-3 - FalconSAT-3 was a training satellite for US Air Force cadets. It was decommissioned for USAF use, and is now used exclusively for Amateur Radio. One of the neat features of it is that it includes a "flying Bulletin Board System - BBS". 
• FLTSATCOM System - Fleet Satellite Communications (FltSatCom) System is a US Navy geosynchronous "bent pipe" wide bandwidth transponder pair of satellites. I wrote an article discussing FLTSATCOM.
• Othernet - Very cool project to do "datacasting" from satellite. Not entirely a new idea, but a new approach.
• Phase 4B Payload for North America GEO Satellite - (Thank goodness for the Internet Archive's Wayback Machine!) This was a well-conceived, well-scoped realistic project that seemed realistic. Apparently the host satellite was canceled. It would have been great for data communications.
• SATNOGS - There are a lot of research (micro)satellites in orbit now from various institutions such as college engineering classes. The problem is that they only realize their potential when the data that they generate can get transmitted back. SATNOGS is a network of open source, inexpensive ground stations that use commodity hardware, 3D printed parts, and the Internet to receive data from these small satellites and get it back to the satellite's sponsors.
• UHF-Satcom.com - Good reference site for satellite information.

Non-Amateur Radio

• Doodle Labs Smart Radio - Doodle Labs Smart Radio series have some interesting capabilities including coverage of some Amateur Radio portions of spectrum. 
• FreeWave Technologies FGR-2 Series of 902-928 MHz Radios - FreeWave Technologies makes the most impressive data radios that I've seen for 902-928 MHz operating under Part 15.247 (license exempt in Industrial, Scientific, and Medical - ISM bands). The primary reason FreeWave radios are so robust is that they use Frequency Hopping Spread Spectrum (FHSS), thus they can "punch through" in the crowded 902-928 MHz band when "static channel" radios cannot.

Speculative Ideas
Includes legacy systems that might be instructive for future projects or potentially revived with current technology.

• APRS as A Hailing Channel - This was an intriguing idea by Bryan Hoyer K7UDR. All Amateur Radio services in an area - Winlink, etc. should advertise on APRS.
• Coastal Chipworks TNC-X - This was a great TNC - KISS so it was really stable.
• DAMA - Another Network Solution - Describes a "Coordinator / Worker" network for Amateur Radio that would reduce collisions common in Collision Sense Multiple Access / Carrier Detect (CSMA / CD) networks.
• Data over Digital Mobile Radio (DMR) - It occurred to me a few years ago that all the Amateur Radio DMR repeaters that are being built are, at their core, data repeaters. The DMR specification makes provisions for data, but no one seems to know much about how to do data over DMR. These Maxon DMR data radios deserve some experimentation.
• Doodlelabs Radios - These were a brief experiment in combining a Wi-Fi chipset with a transverter to use Wi-Fi protocols in the Amateur Radio 420-450 MHz band. 802.11 uses a 22 MHz channel, and transverted to 420-450, it barely fits. Other not-quite-Wi-Fi variants can have a channel size as small as 5 MHz. I have some of these radios and need to find some supporting documentation. Yet again, it's an interesting idea for reimplementation with current technology.
• (Faster) Data over D-Star - Despite the fact that D-Star (as implemented by Icom) is the only digital voice mode that cleanly implements data along with digital voice, the data implementation is (in my opinion) at best an afterthought. In D-Star, 3600 of 4800 bps is hard-coded to voice, and ~300 bps are used for "overhead" (callsign, etc.) and the remaining 900 bps of the payload is data. Icom kind-of fixed this in some later models of their D-Star radios by creating "DV Fast Data Mode" which Icom describes as By using data in place of voice frames, the ID-5100A can transfer data 3.5 times faster (3480 bps) than in the conventional DV mode (with voice). The beauty of DV Fast Data Mode is that (I'm told) it is compatible with any D-Star repeater. I don't yet have a radio (or two, that I'll need to conduct a test) to verify this, but it's on my agenda. 
• David Rowe VK5DGR - His most famous project is Codec2 and FreeDV, open source digital voice modems. He is also working on a "radio", and other projects.
• DFQF2 T7F Data Radio - Like the Kantronics D4-10, this radio is now out of production and mentioned here as inspiration for a hoped-for new generation of data radios for Amateur Radio. The T7F was more advanced than the D4-10, including frequency agility. There were several excellent data radios for Amateur Radio made in Germany, but none remain in production (that I know of).
• D-Star Digital Data Mode / ID-1 Radio and "Repeater" - The Icom ID-1 was the fastest (that I'm aware of) data rate for an Amateur Radio product (that wasn't a kit / science project) at 128 kbps (half duplex). It also had the distinction of being of operating on the forlorn Amateur Radio 1240 - 1300 MHz band. While the ID-1 is out of production now, the D-Star Digital Data (DD) mode lives on in another Icom radio, and a planned successor to the ID-1 repeater. It would be a very cool project to create a new radio with the ID-1's data capabilities.
• Flexnet - Was advanced packet radio networking, that fixed many of the issues of digipeating, mesh networking (Net/ROM). It is reportedly still in use in places, and deserves more research. This discussion and this discussion is helpful. Another technology that should be trivial to reproduce and advance using current technologies.
• IPv6 over Amateur Radio - One of the valid criticisms of IPv4 over Amateur Radio is that the headers were very large, consuming considerable airtime just for the headers. While there were some implementations of header compression in the original TCP/IP over Amateur Radio packages, header compression wasn't standard. In IPv6, header compression is standard, so perhaps IPv6 over Amateur Radio is a "fertile area of research".
• Kantronics D4-10 Data Radio - It's sad that in many ways the long-discontinued Kantronics D4-10 was a high point in packet radio radios. It featured a wide bandwidth that could do 19,200 bps (and faster), 10 watts transmit power, minimal design (no fancy faceplate), and best, was designed for data, not a radio designed for voice that kind-of does data. Because it uses crystals for frequency setting (which are near-unobtanium now) it's not that useful now, but it is a benchmark for what a data radio for Amateur Radio could and should be - minimalist, stable (with the mods mentioned in the link), and reasonable power output (though 25 watts would be better). I include it here as an inspiration for a new generation of data radios for Amateur Radio.
• Networking Over HF - Interesting project!
• NW Digital Radio UDRX-440 Software Defined Transceiver / Data Radio (PDF) - This was a project that came agonizingly close to becoming a product. I profoundly wish it had, even with many rough edges. It was to be a 25 watt multimode data radio with all the features we wanted - flexible modems, full software control of transmit bandwidth, frequency, power, etc. There were good, valid reasons that it didn't quite make it. It's listed here as an example of what Amateur Radio needs as tools to make great leaps forward in becoming relevant again in the minds of most techies.
• OscarDelta IP Over AX.25 - OscarDelta IP Over AX.25 is a packet radio software developed for amateur radio operators to provide TCP/IP communications.
• Puget Sound Amateur Radio TCP/IP Group - My paper for the 1995 Digital Communications Conference (DCC) on the 9600 bps bit regeration repeater network in the Puget Sound (greater Seattle), Washington area. I made this into an article on SuperPacket, with some updates.
• Single Channel Repeater - Single Channel Repeaters have been done, but only as a "record for seconds, then play back for seconds. Instead of that, think receive for 5 mS, then transmit for 5 mS.
• Wildernets - It's hard to grok Wildernets at first, but it's an amazing piece of software. It provides a web server, Voice over IP (VOIP), mesh networking, and more. It was ported to a now hard-to-find Wi-Fi router, and it's hoped that the developer will be able to find more time to work on it.
• WA4DSY 56 kbps Modem - This was groundbreaking in its day and implemented in several areas, including repeaters in Vancouver BC and Atlanta, GA. It's still a fantastic achievement; it should be "easy" to implement this using current RF and DSP technology.

What We Need (In My Humble Opinion)

• Don't fossilize the Amateur Radio spectrum with repeater coordinations. We need more repeaters, especially for data, not the privileged few that the exalted grand poobas of repeater coordination groups deign to give their blessing to. There was an FCC letter once that said (paraphrased) that repeater coordinations give preference to a channel pair, not exclusive usage. So when that repeater isn't transmitting, the frequency pair is accessible to other uses.
• Fix the silly FCC rule that regulates maximum data rate. As Lyle Johnson WA7GXD once famously said (paraphrased) about what the FCC rules on this topic should be: "Here's your frequencies and the maximum channel sizes. Have a nice day." The best example of a well-reasoned modernizing of the FCC Part 97 rules is a 2017 FCC Filing by Bruce Perens K6BP. I agree with almost every point Perens makes.
• An amateur radio payload on a geosynchronous satellite for North America. Europe and Africa have Es'Hail 2. North America came maddeningly close.
• A data radio designed in the 21st century:
  • Operates on 144 MHz and 440 MHz. 50 MHz and 222 MHz would be ideal. Single band units would be acceptable.
  • No display, knobs, speaker, microphone, etc. Just flat audio input and output. Just basic LED indicators to verify power, PTT, etc., and a power switch.
  • Full remote control of operating parameters such as frequency, channel size (25 kHz, 12.5 kHz), CTCSS frequency*, etc.
  • Modern I/O interface - Ethernet preferred, but USB would be acceptable
  • Transmit power selectable 5 watts / 10 watts / 25 watts / 50 watts. There should be (at least optional) big heat sink for longer transmit duty cycles.
  • Fast transmit / receive turnaround time would be ideal.
  • Could even be simplified to be purely a transmitter; we have ample good software defined receivers available now.
• A fully software-defined transceiver for VHF/UHF. One reason I admire Flex Radio is that their products are entirely software-defined; I wish there was an equivalent radio for VHF and UHF.
• A publication that focuses on interesting stuff like the above. I'll be working on that.
• A wideband data radio that operates in the 1240-1300 MHz Amateur Radio band, with reasonable output power.
• A series of companion amplifiers (with filters) for VHF and UHF bands, including 50 MHz for the Analog Devices ALADM-PLUTO to achieve output power of at least 25 watts. If we had such a device, there would be a lot more experimentation with GNU Radio in Amateur Radio. (The problem with existing amplifiers is that the drive level requirement is much higher than what the ALADM-PLUTO can produce.)

 

This page was ported from N8GNJ.org from two previous blog posts (1) (2). I'll revise this page periodically and keep it parked at this permalink URL:

https://www.n8gnj.org/interesting-and-advanced-projects-products-in-amateur-radio.html

Thanks for reading!

Steve Stroh N8GNJ
Bellingham, Washington, USA
Copyright © 2021 by Steven K. Stroh

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