Ham Radio Analysis Paralysis

Lately I’ve been pretty quiet on all ham radio fronts because I’ve been stagnant on getting the ball rolling on a lot of stuff. So I’ve been facing a turning point that’s leading me down a road to learn how to write firm/software – C for Embedded things, C++ for everything else, and python for everything everything else. And GNURadio for radio hacking. However, I’m an Electrical Engineer, and I really want to design and test hardware, but as time goes on everything around me is about software. Even my fiancée is a software engineer!

Life also has priority – I’m 25 years old, so between all my friend’s weddings that I have to go to, I have a wedding coming up next year, I’m trying to travel my butt off around the world with my fiancee, and otherwise generally when I come home I like to cook, clean, play with cats, then sit around and watch YouTube or reddit until I fall asleep.

Stuff on my “want to do this but I’m faffing about” list:

  1. YOTA – I want to lead the charge to bring YOTA to IARU Region II (North & South America).
  2. Ham Radio Hackathon – I think ham radio needs it’s own hackathon. There is a huge opportunity in the hobby to bring hackers and hams together to create some really cool stuff, so I want to cooperate with folks from places like Hackaday, Adafruit, etc to start something up. Cloud logging, improving APRS, connecting DSTAR/YSF/DMR/P25 together, just a few ideas for such an event.
  3. Youtube. I have a lot of ideas of videos to make, but that takes a lot of time to record and edit, and I really don’t get that much inspiring feedback, that many views, no revenue whilst spending about $20/month for Adobe Premiere Student…
  4. Phasing Line Podcast – same as Youtube, but with Adobe Audition. Marty is also busy 110% of the time with Baker Island Dxpedition Social media stuff and being the young ham of the year and all. Earlier this year I also help start the Noisy Key Podcast, which didn’t even get off the ground due to availability of a bunch of teenaged hams and me.
  5. Contesting – my favorite activity in ham radio, but haven’t sat down for a full contest since last year’s SSB sweeps. Weekends are usually spent in new cities, at new food places, at cool bars, or cleaning the apartment.
  6. Projects on my mind:
    1. Project Echoloon – haven’t done anything with that besides the Blog Post
    2. FaradayRF – what I think might be a perfect foray into improving my programming skills, but I’m reluctant to start because I don’t want to buy $300 of radio equipment I might not end up using (except I already bought two Gotenna Mesh’s for $150 for the explicit purpose of hacking them…at least I could resell), and I generally have a disdain for programming I can’t seem to get over: I prefer heat and smoke, not compile errors, when things break.
    3. GoTenna Hacking – same as above, except I realize I need to get dirty with GNURadio, which i’ve been installing and learning for about a year now. Not getting very far. I don’t have a real point to it besides seeing if it’s feasable to use GoTenna on amateur bands, or adopt similar meshing protocols for ham radio.
    4. Mesh Networking with SLSRC Engineering squad – basically go on the roofs of tall buildings, install some networking stuff in the St Louis Suburban Radio Club’s repeater racks, and have fun. In the past I hung out more often, but then their work days were colliding with days I was busy doing other stuff, and eventually got out of touch. Doesn’t help that hteir meetings are on Friday evenings, when I’m either in another state…physically or mentally.
    5. Creating a new amateur radio datalink paradigm/protocol/philosophy – I really like when computers talk to each other. But when it comes to APRS, it makes me very angry – it’s slow, it requires a TNC or computer to create audio tones that plugs into an FM voice radio, and uses packet which isn’t very robust, and the documentation leaves a lot to be desired. I want to see FaradayRF (which uses plain 2-FSK at the moment) to revolutionize amateur radio data to get away from 1.) 1200baud APRS and 2.) having to buy a D-STAR radio to use digital 128kbps “fast” data. or 3.)buying a COTS radio module for a specific task.

Or just find a way to make it easier to connect with D-STAR without having to buy an Icom radio since it’s protocol is already written, and it’s not that hard (in my mind at least) to find a cheap a GMSK modem and microcontroller pair, plop it on a PCB, work some software magic, and boom D-STAR data radio modules. However, I can’t not believe that someone has done this already and the fact this is is also reinventing the wheel puts me off (there’s sooo many radio protocols out there!).

Also, yea yea yea APRS is compatible with every voice FM radio on the market and it was a great use of equipment at the time (which was the late 80s) but now we really need to have our hands on small data radios similar to zigbee and LoRA.

These are the things on my mind. Perhaps writing them all down will help me think about it in a different way.

I will be attending HamJam in Atlanta, GA this weekend, so that’ll be fun and hopefully inspiring. It’s very close to where my fiancee’s family lives (near Alpharetta) so it’s double points.

Anyone else got so much on their proverbial plate that it makes them halt all processes? Let me know in the comments, my twitter, email, etc. for your ways to swim through the mud of analysis paralysis in ham radio.

I’m starting a podcast

http://phasinglinepodcast.com

Marty Sullaway KC1CWF (aka Chicken With Fries) and I are starting a ham radio podcast. We’re kinda winging it, so we’ll see how it goes. No schedule, no topic, no ads (yet.) Just Marty and I having a conversation, two guys and a mic style. We just hope to make something different and entertaining to younger people in the hobby. 

A promo ep is available on iTunes and Stitcher, and the RSS feed for your favorite podcasting app is at http://www.phasinglinepodcast.libsyn.com/rss. Just search Phasing Line Podcast and you’ll find it. 👍

Project Echoloon: A Small, Open Source, Cross-Band Repeater Board for High Altitude Ballooning

I had an idea to do this on a long drive back from a friend’s wedding. As far as I know, there isn’t a lightweight single-board  [removed 10/11/16] solution for a crossband repeater for high-altitude ballooning. If there was, we’d be hearing about it a lot more. We would have contacts via balloon along with via satellite. I aim to develop something cheap and easy to build, and maybe at some point get someone to mass-produce and develop the project further.

[Added 10/11/2016]: I also just really wanted to write this down so I could sleep at night instead of thinking about this idea, to practice writing requirements, which is a day job thing I do sometimes, and to keep my skills up with electrical projects and development, which isn’t usually a thing I do in my day job.

This has been done before, but not in a very thorough manner. I’ve searched google for high altitude balloon, and found a few things, from a crossband repeater on EOSS’s site, to student senior design projects, and a few other projects here and there, but nothing as organized or mass-produced as it can be. Basically, I would like to take the current APRS high-altitude balloon digipeater and beacon hype and turn it into a crossband repeater high-altitude balloon hype and make a sort of special operating event, contest or award scheme out of it just like today’s ham radio satellite communications.

This isn’t yet a completed design, it’s more like my personal notes on the project. It’s in active development, and it may never be complete – I’m a busy person with a busy life, and I certainly don’t have the time now to devote to it, but hopefully either soon I will, or someone with the time will take it and run with it, so long as open source design practices are followed. You can certainly make and sell the project commercially, just please keep it open.

For those interested in traceability, this is the first release of any information dealing with the project. If it gets momentum, I’ll put it on Github. Edits to this page will be denoted by <thing added> [added <date>]or <removed thing> [removed <date>].

I shall call it Project Echoloon. Not to be confused with http://www.echoloon.com/. Name subject to change lol.

Project Echoloon

Project Echoloon is an Amateur Radio cross-band repeater device that can be lifted by a few helium or hydrogen-filled party balloons. It will also contain an APRS transmission capability so that users can be somehow notified that the repeater is in the area, to know exactly where to point antennas at, and to allow it to be easily recovered. It’ll be very low power so it can operate during several minutes or hours before the balloons burst and the device falls back to earth [added 10/11/16] within recoverable range.

It’ll be powered by a small Li-Ion or LiPo battery and possibly a small array of solar panels. It should allow for at least 8 hours of operation during good sunlight.

It shall be cheap – no more expensive than a Baofeng. In fact, it’ll probably use the same RF chips that are in the Baofengs and other chinese radios. It will have adequate filtering too. $25 is my first guess for an initial price. I’m not doing this for a profit until it’s in a manufacturer state.

It should be recoverable too, being tracked by APRS and having a transmitter to radiolocate. Once it’s impacted, a strobe LED will also blink and an audible alarm will go off. We could even put a Tile on it or something for the last 100ft.

I think a parachute adds too much weight and the device will be light enough so that if it falls at terminal velocity it won’t be damaged. It’ll go in a small foam case to help thermal stress, help cushion its impact and float if it goes in water. It should not be allowed to go too far so that A.) it doesn’t go out of the country and B.) you don’t have to drive too far to recover it. It could be modified for circumnavigation at some point, but it’d have to have a lot more logic to stay legal in every country it may be over.

The design, software, hardware and documentation will be open source. I hate closed source projects in ham radio with a FIERY PASSION. It’s cool you want to make a buck, but you can still make a buck making stuff open and freely available for anyone to improve it or build it themselves. That’s the spirit of ham radio.

Requirements

  1.  Function(s)
    1. Simulcast half-duplex voice FM repeater
      1. Echoloon (herein referred to as “The Device”)shall receive FM voice signals from 2m band, and simultaneously re-transmit them on 70cm band OR vice versa
        1. Need to do a trade study between TX/RX bands. APRS beacon may favor transmission on 2m band whilst power requirements may favor UHF band for use with high-gain antennas.
      2. The device shall not interfere with any other repeater or satellite repeaters i.e. frequencies must be coordinated.
  2. Control
    1. The Device shall be remote-radio-controllable on an unpublished frequency.
      1. The Device shall receive DTMF codes and convert codes into control input.
    2. In the event of interference caused by the device, The Device shall be able to disable transmission functionality via a DTMF command. [FCC CFR §97.109(d)]
  3. Identification [FCC CFR §97.119(a)(b)(1)]
    1. The Device shall announce its FCC callsign in 20WPM CW every ten minutes.
    2. Every thirty minutes during positive climb or level flight, The Device shall announce “This is Project Echoloon – a high altitude balloon crossband repeater, currently at <height> feet over gridsquare <6-digit gridsquare locator>. Please use <input frequency> megahertz with PL <PL tone> hertz.
  4. Size, Weight and Power (SWaP)
    1. Size
      1. Circuit board shall be 2″ x 3.5″
      2. PCB material shall be two-layer FR4, 0.031 inch thickness.
    2. Weight: The Device shall be capable of being lifted by a number of common party-style latex or mylar balloons. Weight not to exceed 50 grams.
    3. Power
      1. Trade study on battery and solar panel configuration
        1. Battery only
          1. Short duration
      2. Solar only
        1. Not enough power, especially in clouds
        2. Very light
        3. Complex circuit design
      3. Both Battery and Solar
        1. Longer operation
        2. Heavier and more complex circuit design
      4. RF Power Output not to exceed 50mW
  5. Flight
    1. The Device shall be capable of being lifted by common helium-filled party balloons, either latex or mylar.
    2. The device shall be capable of reaching maximum height of 100,000 feet, then bursting.
      1. Upon bursting, the device shall go into recovery mode, where APRS begins to beacon more frequently (see recovery).
  6. Cost
    1. The Device shall be affordable to everybody.
      1. Material cost shall be less than $25
  7. Tracking & Recovery
    1. APRS Beacon
      1. The Device shall transmit its GPS position and a message containing repeater input/output frequencies, device name, and website on the APRS frequency.
      2. The Device shall share the same RF transmitter and antenna to transmit the beacon packet
        1. This will cause a temporary outage of repeater functionality that is not detrimental to its use.
      3. The device shall beacon it’s position every 5 minutes during ascent
      4. During descent, the device shall beacon it’s position as a function of altitude: less height = more beacons.
        1. Beneath 5000ft altitude during descent, APRS path settings shall change to WIDE-2 to make use of digipeaters with greater hops for recovery.
    2. Alternate Modem?
      1. [Added 10/11/16] Unit shall be capable of interfacing with other devices (such as a integrated APRS tracker/data radio) through USB/UART/Serial/I2C/???
    3. No parachute shall be required.
      1. This device will fall at terminal velocity but be protected from impact and thermal stresses by being enclosed in a small foam case.
    4. Post-descent recovery
      1. Upon impact, the Device shall transmit its FM CW ID and a 3 second tone every 30 seconds on it’s published repeater output frequency for RF direction-finding.
      2. The device shall have an audible buzzer and bright strobe LED for locating.
      3. The device shall have contact information written on it.
  8. Licensing
    1. The Device shall be open source.
      1. Hardware shall be licensed under the TAPR Open Hardware License
      2. Software shall be licensed under GNU GPLv3 License
      3. Documentation (including these requirements) shall be licensed CC-BY-SA-4.0. See below.
    2. I don’t know how to properly “license” anything so help shall be given to Sterling on how to do this. Regardless, I don’t care how it ends up but I do not want it to end up in someones hands as a closed-source for-profit project.
  9. Hardware and Software Development
    1. The Device shall use freely available or open source tools for schematic capture and PCB layout such as Cadsoft Eagle Express or Kicad.
    2. Hardware and software files shall be hosted on a public Github page.
  10. Mechanical Design
    1. The Device shall be encased in a small foam block to aid in thermal relief and prevent damage upon impact.
    2. Antenna
      1. Linear or circular polarization?
      2. Wire, dipole, rubber duckie, cloverleaf?

You’ve reached the end of my work so far. Stay tuned on the N0SSC twitter and this post, and soon a GitHub page, to be created.

To do:

  1. Finish requirements
  2. Power source trade study
  3. Research RF system-on-chips and filter designs
  4. Find a volunteer embedded ARM developer or figure out how to do  arduino or something…
  5. Discover how difficult or expensive 90% of these requirements are, and then remove them lol.
  6. Finish Requirements
  7. Develop BOM
  8. Develop schematic
  9. Develop layout
  10. Send to OSHPark for first prototype
  11. Fix problems
  12. Get second prototype with hopefully zero problems
  13. Burn through any money and time I had finalizing the product
  14. Marketing for interest-gathering
  15. Crowdfund $1500 or so, something modest
  16. Fund run of 50 boards
  17. Build them after 4 months of delays and parts stock issues
  18. Ship to backers.

Sorry this numbered list is gross, I don’t know CSS or HTML enough to make it look pretty.

Also,

Creative Commons License
Project Echoloon by Sterling Coffey, N0SSC is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.
Based on a work at http://n0ssc.com/posts/238-project-echoloon.

👍

 

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