Many, many moons ago (mid-80s) when N5UWY was in paramedic school, his instructor for the ACLS portion would go off on tangents and always referred to those tangents as “cultural enrichment”. Mostly those tangents were relevant but not always. When W5JA and N5UWY were teaching a license class back a couple years ago, the latter started highlighting questions that had come up in class with answers expanded as necessary. He plans to do the same this year; consider this “cultural enrichment”. Watch for and icons.
Countries – what do they mean in amateur radio? Well, it’s a little different than what the United Nations considers a “country”. Not only are actual political countries considered but also, let’s call it “degree of difficulty”. So not only does the United States of America count as a country but so do Alaska and Hawai’i. This scoring system was devised, believe it or not, in the 1930s. Clinton B DeSoto, Assistant to the Secretary, ARRL, wrote an article describing his proposal in the October 1935 number of QST. The ARRL has the article online. The current list of ARRL-recognized “DXCC Entities” is online as well.
19″ is 2 meters? What did Mark say??? Here’s the math. The “2 meter band” runs from 144 to 148 MHz. If you do the math to calculate the wavelength (this is repeated further down) you will find that 144 MHz has a wavelength of 2.082 m and 148 Mhz has a wavelength of 2.026 m. Now, a common vertical antenna is 1/4 of a wavelength (or λ) long. One fourth of 2 meters is 50 cm (or 0.5 m). And how long is that 50 cm in inches? Yep, 19.6″. So he’s not crazy.
Earth-Moon-Earth communications. Usually abbreviated EME (or E-M-E) and sometimes known as “moonbounce”. Yes, it is possible to send a signal to the Moon and hear the signal after it bounces of the surface a few seconds later. The military tried this in the 1940s and amateurs started trying it in the 1950s with the first succcessful two-way amateur QSO via the Moon taking place in 1960. One of SCARS’ members, “Lucky”, W7CNK, holds several firsts in the realm of EME communications:
- 1970-03-15 – first EME QSO on 220 MHz (with WB6NMT)
- 1987-04-07 – first EME QSO on 3456 MHz (with KD5RO)
- 1987-04-24 – first EME QSO on 5760 MHz (with WA5TNY)
Items from past classes
Phonetic alphabets – (click to embiggen): I’ve not found a good article on the history of phonetic alphabets (also called “spelling alphabets”). The chart here was assembled from a couple of sources. The “ICAO” alphabet has been around for over 60 years with a couple changes. The International Civil Aviation Organization came up with it in response to growing international air travel. After the Second World War everyone “agreed” to use English on the aeronutical frequencies (various HF assignments, plus 108-136 MHz, AM, for civilian and 225-400 MHz, also AM, for military use) there needed to be a common way for radio users, many of whom were not native English-speakers, to spell things out when necessary and the standard alphabet was born. The same alphabet has since been adopted by NATO (and, because of that, the national militaries that make up NATO) and amateur radio. For nearly as long, APCO, the Association of Public-Safety Communications Officials (but originally the Associated Police Communications Officers), has used their own list. If you search for the history on the excellent apcohistory.org site, you’ll see repeated suggestions that APCO adopt the ICAO alphabet. To date, that hasn’t happened. Maybe that’s a good thing “1 ALPHA 12” wouldn’t have sounded right.
Some common abbreviations -Most of these are abbreviations used by Morse telegraphers and probably should only be used in CW or Data communications.
- CQ – Used to establish communications with any station. “Seek You”. Any mode.
- DE – French for “from”, as in “CQ CQ CQ DE N5UWY”. CW, Data modes.
- 73 – Best Regards. Not “73s”! That would be “best regardses”! Any mode.
- K – Back to you. CW or Data (or NYC Police and Fire!).
- DX – Distant station. Any mode.
- QRS – Send more slowly. Reduce Speed. CW only.
- QTH – What is your location? Location.
- QSL – Can you acknowledge? Acknowledged. Also used for post cards that hams send to acknowledge a contact. Send Log.
- QRL – Are you busy? I am busy. Popularly used as “is the frequency in use?” which is what you would say on HF phone.
- QSY – Should I change frequency to …? Change frequency to … .
- QSO – Can you communicate with … ? I can communicate with … . Popularly, any contact.
- QRZ? – Who is calling me? You are being called by … . Popularly used in phone contesting as shorthand for “next station please!”
Band Nomenclature – first a picture (click to embiggen):Now, some words: I put this together when I got curious about the letters assigned to our various microwave bands. Then there are the other names (HF, VHF, etc) and they seemed to cause some confusion the other night; let’s see if this helps (or hurts!).If you read enough old stuff about radio, particularly QST, you’ll note that before a certain point, everything above the 10-meter band was known as “u.h.f.” What is now The World Above 50 MHz was titled On The Ultra Highs. It appears to have started in the 1930s and covered activity on what was our 5-meter (56 mc.), 2 1/2-meter (112 mc.), and higher allocations. I’ve googled and googled and can’t find when the decision was made to go to HF/VHF/UHF. I did discover that the column name changed in 1943. In fact, it was On The Ultra Highs in the March issue and was retitled On The Very Highs for the May issue. I thought there would be an article in the April issue explaining the new nomenclature. Sadly, there is nothing. Still looking.
Flex Radio Systems – This is the Flex 1500 that was passed around in class.
Radio Propagation phenomena – Tropospheric Ducting often occurs above about 50 MHz and allows “greater than line of sight” communications with stations out to about 800 km or more (about 500 miles). The E layer of the ionosphere can also support communications on VHF and higher bands when “thin clouds of intense ionization” occur. During these “Sporadic-E“, or Es, events signals may be heard up to 2500 km away! (about 1500 miles). The peak season for these events in May, June, and July. N5UWY’s best DX via Sporadic-E on 144 MHz was made during a huge opening back in June of 2010. The QSO was made with K1PXE in Maidenhead grid square FN31ke near Bridgeport, Conn, a distance of about 2200 km. Pat Dyer, WA5IYX, who recently became a Silent Key, co-authored an excellent article about Sporadic-E propagation in a 1992 issue of QST magazine. Doug, KC5JUS, a forecaster at the Norman National Weather Service Forecast Office, likes to listen for distant FM broadcast stations. You can clearly see from his map that there is a “donut” of no reception between the green dots and the red dots. The green indicate stations (most likely) received using tropospheric ducting as the propagation mechanism while the red indicate those (most likely) received using Sporadic-E as the mechanism. Meteor Scatter – Gary mentioned bouncing signals off of the ionization trails left by meteors entering the atmosphere. There is a website where meteor scatter enthusiasts chat and make meteor skeds known as Ping Jockey. Not a particularly pretty site, but has a lot of info on this exciting mode. Remember, if it ionizes the ionosphere, someone is bouncing signals off of it!
Microwave – Hams have a bunch of assignments above 450 MHz.
- Comet GP6 dual-band fixed antenna.
- MFJ’s version of the “ham stick”.
- Build your own 1/4λ ground-plane antenna!
- Rubber ducky, you’re not the one?
Open-wire feedline – Window line? Ladder line? Twin-lead? What? Here is a good synopsis.
Modulation categories – There are three broad (very broad) categories of modulation:
- radiotelegraphy – on-off keying of a carrier usually using Morse code
- radiotelephone – transmission of voice by any means (including, oddly, digital modes)
- radioteletype – transmission of data by any means
Oddities here: Radiotelegraphy — testing for which, in the amateur service, was phased out between 1991 and 2007 — is pretty straightforward: it’s Morse code. Sent by straight key, “bug”, electronic keyer, or computer, doesn’t matter.
Radiotelephone is any mode that encodes human voice and transmits it over radio. This includes single sideband (SSB), amplitude modulation (AM), frequency modulation (FM), or … oddly … digital modes like JARL’s D-STAR or ETSI’s DMR.
Radioteletype is actually a generic term for data being transmitted over radio for mechanical reception at the other end. In the amateur service, radioteletype, usually abbreviated RTTY, usually means Baudot-encoded data sent by shifting the frequency of a transmitter. This is known as frequency-shift keying, or FSK. In fact, hams are usually even more specific when they say “radioteletype”: they usually mean Baudot-encoded data sent at 45.45 bauds using a shift between the mark and space frequencies of 170 Hz. But really, radioteletype is a generic term and in the FCC regs, any time they use the term “radioteletype”, think digital modes: RTTY, PSK31, THROB, JT65, whatever.
Why is the 10-meter band not 30 MHz? – Well, a couple reasons. First, not all the frequency allocations we have today (see 47 CFR 97.130, for example) are what we had 80 or 90 years ago. At one point, all our bands were almost perfectly aligned “harmonically” … 160, 80, 40, 20, 10, 5, 2.5, and 1.25 meters. Well, we’ve added to that and moved some stuff around since then so it doesn’t work out as nicely. More to the point, in most cases we’ve rounded. It gets pretty confusing on the longer-wavelength bands, especially 80 meters. Or is it 75 meters? Well, do the math as below. The band runs, in megahertz, from 3.5 to 4.0 MHz, so …
300 / 3.5 = 85.7 meters 300 / 4.0 = 75.0 meters
In everyday amateur use, hams usually mean the phone end of the band when they say “75 meters” and the CW/DATA end of the band when they say “80 meters”.
The math on 10 meters looks like this:
300 / 28.0 = 10.7 meters 300 / 29.7 = 10.1 meters
Yeah, we round.
Remember, the longer the wavelength, the lower the frequency.
Frequency vs Wavelength – As Phil said, 300/f (where f is the frequency in megahertz, MHz) yields wavelength in meters. The 300 stands in for c, the speed of light. The speed of light is actually 299,792,458 m/s (meters per second) but because we’re using millions of Hertz, we can take out a bunch of zeroes and round to “300”. The fun thing is (well, fun for nerds) is that 300/λ (where λ is the Greek letter Lambda which is used to denote wavelength) yields the frequency in megahertz!
Local sources for ham stuff – There are a few places locally where you can pick up items. Some of the vendors listed are expected to be exhibitors at this summer’s Ham Holiday hamfest in OKC.
- Clear Signal Products, a/k/a The Coaxman – Mustang, Oklahoma – Feedline of all types, antenna wire and support rope, connectors. See site for more.
A little further away:
- B & H Sales – Derby, Kansas (176 miles) – Radio Shack dealer (as opposed to the former corporately owned stores) that carries many ham radio items.
- Ham Radio Outlet – Plano, Texas (186 miles) – full line dealer and mailorder.
- Texas Towers – Plano, Texas (186 miles) – full line dealer and mailorder.
- Main Trading Co – Paris, Texas (211 Miles) – full line dealer and mailorder.
Decibels – 1) The Bel is named after Alexander Graham Bell, inventor of, among other things, the telephone. Where the 2nd l went, I have no idea. We almost always deal in tenths of a Bel, or decibel. 2) If I double the power out of my transmitter, the other station will see about 3 dB improvement in my signal. Likewise, if I cut my power in half, the other op will see about a 3 dB decrease. Since an “S unit” is commonly accepted to be 6 dB, that’s about a half an S-unit either way (more on that below). 3) If I increase (or decrease) my transmitter’s power by a factor of 10, the other op will see about a 10 dB increase (or decrease). That’s a little less than 2 S-units. Think about that: the difference between a 100-W “barefoot” rig and one that has a 1000-W amp (a “full gallon” in ham slang) is about 2 S-units. 4) You can add the dBs. If I increase my power by a factor of 4, that’s 6 dB. How do I know? Because that’s the same as doubling it and doubling it again. You get 3 dB for the first doubling, another 3 for the second, add them together and that’s 6 dB. Note that I never went near a logarithm! Note that this is all true for power ratios (10 log P2/P1), but not for voltage ratios (20 log V2/V1). Some dB resources:
- http://www.astrosurf.com/luxorion/qsl-db-power-units.htm – basic, but not apparently written by a native English speaker.
About those S-Units. There is no actual standard for what signal is associated with an “S9” signal. The original convention, developed decades ago by Art Collins, W0̸CXX, founder of what became Rockwell Collins, was that the signal at your receiver’s antenna terminals was 50 µV (50 millionths of a volt) was S9. If you’re into dBm, that’s -73 dBm. Every S unit below S9 was a drop of 6 dB and every dB above was just shown as so many dB “over” S9 up to 60 dB, usually in increments of 10 dB. The IARU’s Region 1 has codified that as Technical Recommendation R.1 (Note that the Americas are in IARU Region 2).
Callsigns – The International Telecommunications Union coordinates all radio callsigns to prevent duplication. They maintain a listing of all allocated callsign blocks. The USA is allocated the following blocks:
From there, the FCC decides how to allocate calls to individual radio stations in the various radio services that it regulates.
Amateur services worldwide (with very few exceptions), have callsigns consisting of a prefix that includes a digit and suffix of one to 4 letters. International examples would be 7K1AAA, a Japanese callsign where 7K1 is the prefix and AAA is the suffix or VE2DO, a Canadian callsign where VE2 is the prefix and DO is the suffix.
Local examples are N5UWY and W5JA where N5 or W5 is the prefix and UWY or JA is the suffix. The former was sequentially issued by the FCC (at the time, Technicians and Generals received “1×3” calls starting with N) while the latter was obtained via the vanity call program.
For sequentially-issued callsigns, the prefix determines where the amateur licensee was located when their license was issued. Those numbers date back to the original “Radio Inspection Districts” from 100 years ago! The FCC publishes explanations of the various amateur service callsign systems.
Digital Modes – So many digital modes. KB9UKD has a lovely page with audio samples of all sorts of bleeps and boops that you might hear on not only the amateur bands but the commercial bands as well. G3UCJ has another site that has more of a ham focus and he shows what the software looks like so you can see that waterfall we mentioned.
On-Line Repeater Directory ArtSci has a good on-line listing of repeaters in the U.S., at http://www.artscipub.com/repeaters/
Channel list for the two meter band – I made this list because I couldn’t find one. With the exception of the (newish) 60-meter band amateur frequency allocations are not channelized below 29 MHz (the FM portion of the 10-meter band) – operators are relatively free to pick an unused frequency and begin communicating. Above that line and below our 23-cm allocation (1240 Mhz) most bands are channelized, at least in part. The 2-meter band is the one I hear questions about most often, but I could not find a good list, hence the link above. Note that the spacing between the channels in the channelized portion (where FM and digital communications take place) varies by state. Most states use a 15-kHz spacing (OK/AR/MO/KS, for example), while several western states use 20-kHz (Texas, notably). Oddball Alaska uses 60-kHz and southern Nevada uses 30. The far right column indicates into which channel plan each of the channels on the far left fit.
Varistors – I didn’t know what this was, either, exactly. Or if I did know, I’d forgotten. Yes, it’s a contraction of variable resistor, but not variable through manual adjustment. The most common way you will encounter them is in over-voltage protection devices in the form of a metal oxide varistor, or MOV. The MOV has a very high resistance until a threshold voltage is reached, at which point the resistance drops. Since the MOV is usually connected between the circuit being protected and ground, this disipates the transient voltage spike. See the Wikipedia article for details and references to other sources.
Circuit Symbols – The slide from the book had a lot of cultural enrichment on it. If you look through the question and answer pool (which is, by regulation, in the public domain), you’ll see that for the Technician test you only need to know the symbols for the following components:
- Light-emitting Diode
- Variable Inductor
- Variable Resistor
The General test will include a few more symbols, but this is it for Tech. You’ll also need to be able to identify simple switch types. And there will be block diagrams!
Jud’s Crystal Radio Rocket – Click for details.
Peter had one, too!
SKYWARN Severe Weather Spotter Training – Many hams participate in severe weather reporting nets. If you are interested in severe weather spotting and want to participate in your local net, you’ll need to participate in a spotter training session from the National Weather Service. A list of training sessions, both live and on the web, is available from the NWS Norman site.
Heeeeeere’s Johnny! – Apparently, Single Sideband Suppressed Carrier was invented by Johnny Carson! OK, it was John Renshaw Carson, and not “that” Johnny Carson, but he was the guy. As with many communications innovators, he was employed by the American Telephone and Telegraph Co.Update: I just listened to Ham Nation for the first time. Very well done. And, more importantly, they make the same Johnny Carson joke! Episode 81 has a history of single-sideband.
Northern California DX Foundation beacon system – Information about NCDXF’s worldwide propagation beacon system.
Electromagnetic Spectrum Chart – This chart can be printed out on a plotter or other large-format print, wrapped around the appropriate-sized mailing tube, at which point it makes a spiral! Most importantly, it lists where the submarines transmit! (About 13 kHz to about 40 kHz)
Software for Macintosh systems – I was asked about exam practice software for Macintosh computers since the program on the disc only works with Microsoft’s Windows. Lo, and behold, there is a whole website devoted to Mac Ham Radio. Better yet, there are tutor programs listed! I make no warranties expressed or implied as to the usefulness or merchantability of any of these programs!
Ham Nation – Ham Nation is an internet-based TV show on TWiT TV all about ham radio. Bob Heil, K9EID, of Heil Sound, is the host with various co-hosts and guests. Looks like it runs live on Wednesdays at 2000 local time (0200 UTC Thursday).
Morse Code Resources – Knowledge of Morse Code has not been required for US amateurs since 2007 but there are still thousands of hams who use Morse — often known as “CW”, short for Continuous Wave — on a daily basis. Tune in to just about any band on the weekend of the CQ Worldwide DX Contest CW weekend if there is any doubt! If you have any interest in learning the Morse Code, there are a number of on-line and on-air resources. As is often the case, the ARRL has an excellent list of resources to get you started. The ARRL’s headquarters station, W1AW, also transmits Morse Code practice sessions several times per day on several HF radio bands. See the W1AW operating schedule here.
International Operation – It used to be something of a pain to operate from areas outside the FCC’s jurisdiction. The exception was Canada, where a 1950s-era treaty provided the ability to operate without any paperwork. That treaty is still in force and you can simply arrive in Canada and operate your Amateur Radio Station. When it comes time to send a station ID, you simply use your callsign followed by the call area in which you are operating, e.g., “N5UWY portable VE2”, and at least every half-hour say where you are (“80 km north of Montreal”).For other countries, it used to be difficult, took months for approval, and usually cost a couple bucks on top of postage. In the last 20 years, that’s changed for the better. The USA is signatory to two agreements, one with CEPT, the European Post and Telecom organization, where all that is required to operate is your FCC license, your passport, and a copy of the tri-lingual FCC notice, and the other with CITEL, a similar organization affilated with the Organization of American States that covers North and South America, where it’s a little more involved, requiring a $10 International Amateur Radio Permit (available from the ARRL). These descriptions are simplified and not all countries are members of those two organizations, so be sure to check the ARRL site on international operations before making your travel plans!
Digital Audio Radio Service – The DARS is the service in which Sirius XM is licensed. The service operates in the the S-Band, between 2320 and 2345 MHz. These frequencies are in the middle of the 13-cm amateur band, which runs in two swaths from 2300-2310 and form 2390-2450 MHz. That middle swath of spectrum was removed from the Amateur Radio Service specifically to create what became DARS. More information on Amateur microwave here.
Logs – Although logs are no longer required by rule and haven’t been since 1984 it’s still a good idea to keep one. Here’s an article on the ARRL website all about logging. Remember, you can conceivably be talking with operators all over the world and while it may be quarter to noon here, it very likely isn’t where the other station is located. As a result, most hams keep their logs in Coordinated Universal time, or UTC. You’ll sometimes hear this referred to by the military descriptor “Zulu” or the obsolete name “GMT”. Link to accurate time from NIST.
60 m – Technician-class hams don’t have access to the 60-m HF band. Hopefully, though, many of you will choose to upgrade General and take advantage of this relatively new (2003) band. The rules for using this band have recently changed and the ARRL has published a guide to its use. If any questions in the General class Q&A pool are made obsolete by the rules change they will be withdrawn from use, so don’t worry about having to study “wrong” information.
630 m – At the 2012 World Radiocommunication Conference (WRC-12) amateurs were allocated a new MF band at 630 meters. Yes, 630 meters! The new band, along with a new allocation at 2200 m (yes, that’s over 1 mile), was finally made available for US hams in 2017. The ARRL has some preliminary details from 2012. Current information is available here.
Azimuthal Map – A map of the world using an azimuthal projection will show you the correct beam heading to any part of the planet. You can make a map centered on your location at the AZ_PROJ map site. If you don’t know your latitude and longitude, you can use a Maidenhead Grid Locator instead. Norman, and Central Oklahoma are in EM15 and the National Weather Center is located at the more precise location of EM15ge. Maidenhead Grid Locators, or more commonly just “grid squares” are used on the 6-meter band and higher. Work and confirm stations in 100 or more grids on a band and you can get an award.
One of the SCARS members, Ralph, KA5RUZ, and his antennas were mentioned. Here is a look at what he has done.
“Anti-Islanding” – Underwriters Labratory has a standard, UL1741, that (assuming the solar or other co-generation equipment is installed to code!) ensures that any equipment on “load side” of the power circuit goes OFF if the “source side” goes off. This prevents the backfeeding talked about in class. Here’s some more info on UL1741. Along the same lines, a permanent stand-by generator needs a transfer switch for the same reasons. Here is some more information on those.