Tag Archives: Wi-Fi and Amateur Radio

Enhance Your Wi-Fi Mojo With Old-School Radio Hobbies

I have this odd love of some really arcane signals. With a modest but decent receiver from Tecsun (the PL-880), I take advantage of the winter months in the northeast (less atmospheric electricity and no thunderstorms) to “hear” these quirky Longwave signal churn out slow Morse Code identifications. It’s utterly addicting to the right-minded radio geek, and also draws large parallels to what goes on with Wi-Fi that help reinforce my WLAN foundational knowledge.

For wireless networks , we know that output power, antenna choices, the environment where we’re operating, and the capabilities of the client devices all contribute to whether Wi-Fi is “good” or “bad”. If the signals can’t get through, then the microprocessors involved can’t turn those signals into data. Let’s talk about what it feels like to listen to NDBs for a bit, then how that relates to Wi-Fi.

I live about an hour south of Lake Ontario in the middle of New York state. With my beloved Tecsun PL880, I recently received an NDB signal from Pickle Lake’s little airport in Ontario Canada. This location happens to be several hundreds of miles away. The beacon transmitter (considered a “navigation aid”) at the airport generates a fairly low-power cone of  signal into the sky, more or less straight up (that’s the non-directional part of “NDB”). The intelligence in the signal is simply slow Morse Code continuously looping the letters Y-P-L. See this link for  information on the airport.

Pickle Lake

Given that any beacon is typically low powered and pointed straight up, finding them on the air from afar is a sport unto itself. Longwave spectrum sits below the AM broadcast band, way down where frequencies are measured in kilohertz.  It’s absolutely cluttered with man-made signals, and is at the mercy of natural electrical interference, like lightning strikes (called “static crashes” int the radio world). Yet I was able to discern that slow Y-P-L signaling from across a huge Canadian province and a Great Lake, making it an accomplishment as a signal-chasing radio hobbyist.

If you’re not familiar with Morse Code, that Y-P-L formats like – . – – / . – – . / . – . . (dash-dot-dash-dash/dot-dash-dash-dot/dot-dash-dot-dot).

In 802.11 WLAN, specialized modulation helps to ensure that the important signals prevail despite RF conditions being crappy enough to kill narrow-band signals. I see Morse Code is somewhat akin to spread spectrum when I’m chasing NDBs as the dots and dashes can often be heard through really bad conditions that would utterly destroy voice signals. (This is actually why Morse Code was created and used as a mainstream long-distance radio communications mode for so long.)

When Wi-Fi signal quality is degraded, data rates will decrease. When I hunt down NDBs like Y-P-L signal, I might have to listen to each for several minutes and manipulate the filters on my receiver before I know what I’m actually hearing- and sometimes I just can’t quite clarity.  For this and other radio activities, my own ears and mind are the actual microprocessor. Call me silly,  but each beacon identified is like catching a nice fish and brings it’s own little flicker of excitement. Here’s a great list of Longwave NDBs out there to chase, and there are many other lists to be found online.

For improved reception, I could connect my PL880 at to a better antenna, just like in Wi-Fi. I could improve my “data rates” (or words-per-minute copying) by using better filters and practicing my Morse Code more. This would make me a better “microprocessor” in this activity.

Really geeky stuff, eh? I have no problem wearing that label. I also know that there are other radio nerds out there in the WLAN community, as well as those who want to learn more about radio “stuff” beyond Wi-Fi. For those folks, I’ll be teaming up with Scott Lester to present “Radio Hobbies for the WLAN Professional at the 2019 WLAN Professionals Conference. Sign-ups start mid-December, and I hope to see many of you there!

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150 Watt Wi-Fi? Sure- And It’s Legal, For Some Of Us

The world of 802.11 is generally a realm where we measure our power in milliwatts, and are mindful not to stray past our legal limits. we can get a little beefier when doing 802.11 point-to-point links, but this is generally a discipline where we aim for the lowest power needed to keep things in good order and allow for channel reuse in relatively close quarters. This doesn’t register as news to my fellow WLAN professionals, I know. But I would wager that not everyone realizes there is more to the power story, at least in the 2.4 GHz space. That is, if you have an Amateur Radio license.

STOP! Don’t run away- I’m not recruiting, and this is actually pretty easy stuff.

A few quick facts:

  • My son got his Technician Class license when he was 12
  • Long gone are the days when you need to know Morse Code for even the highest license class
  • It’s cheap- the whole thing will run you under $20
  • Practice exams are available for free, here’s one example site
  • Like with Twitter handles, your call sign will only add to your already powerful allure
  • There are all sorts of cool radio-meets-networking-and-Internet places you can explore

Back to topic.  In exchange for the time you put into getting your ham radio license, you’ll become part of a large, international group of tech-minded hobbyists that often work their rigs as much for the public good as they do for their own enjoyment. But… even better, you get to use up to one-hundred-and-fifty-friggin’-WATTS of Peak Envelope Power  in 2.4 GHz!! The truth is that hams use the least power needed to accomplish whatever it is they are trying to do, but that sort of power availability really makes for interesting possibilities, from fun signal-throwing experiments to high-power bridging for public service.

Here’s one nice introduction to the notion, and there are plenty of others if you wield the power of Google to find them. It all comes down to FCC Part 15 (Wi-Fi) versus FCC Part 97 (Amateur Radio) and where they overlap in the low end of the 802.11 space. Even if you don’t take the plunge, just reading about what has been accomplished with high-power 2.4 GHz will get your imagination going.

I’m KI2K, by the way. I’m not super active these days, given my busy schedule. But on the right day, I seriously enjoy my Extra Class radio privileges. If you need any help getting started, just let me know. Also, ARRL is a great first stop.

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