[HN Gopher] Scenes from the last operational Morse-code radio st...
___________________________________________________________________
Scenes from the last operational Morse-code radio station in North
America
Author : fortran77
Score : 139 points
Date : 2024-03-02 14:22 UTC (1 days ago)
(HTM) web link (www.theatlantic.com)
(TXT) w3m dump (www.theatlantic.com)
| ddol wrote:
| KPH receiving station is 45 miles north of San Francisco, without
| bridge traffic you can make it in a little over an hour.
|
| My father-in-law was an engineer in the navy and loved seeing the
| morse & radio equipment.
|
| But the trip was fun for all the family; the driveway up to the
| reviving station building is lined with Monterey cypress trees,
| which have grown into a tunnel. [0] It's a beautiful scene, my
| wife and mother-in-law were really taken aback.
|
| [0] https://www.nps.gov/places/point-reyes-cypress-tree-
| tunnel.h...
| cylinder714 wrote:
| The Maritime Radio Historical Society, KPH's website:
|
| https://www.radiomarine.org/
|
| The volunteers fire up the transmitters every Saturday; the
| schedule is on the website.
| 1st1 wrote:
| Direct link to photographer's site with photos:
| https://www.annhermesphoto.com/radio-squirrels
| resters wrote:
| Don't forget that morse is still used by amateur radio operators
| worldwide.
| jmclnx wrote:
| I am curious if its use is dropping off. I heard knowing morse
| is no longer a requirement to get a license.
| vetrom wrote:
| It is no longer a requirement, but there is a significant
| amount of amateur spectrum where CW (morse) is the preferred
| or only permitted modulation.
| dbcurtis wrote:
| It is no longer a license requirement.
|
| It is still used for casual contacts by people that enjoy it.
| It is used for various things that fall under the banner of
| "radiosport" -- for my part I enjoy Morse-code-only radio
| contests. It is used for identification beacons for repeaters
| or propagation beacons. And for radio experimenters, a Morse
| code transmitter makes a great first project since it is so
| simple and is foundational to everything that comes after it.
| Pretty much any transmitter that you build is just extra
| stuff on top of a Morse code transmitter in one form or
| another.
|
| Morse code has a distinct signal-to-noise ratio advantage
| over any other simple modulation scheme, since the receiving
| filter can be so narrow, and 100% of the power is going into
| the carrier any time you are key-down. This is why Morse code
| is good for propagation beacons and also for other
| experiments. There are, of course, modern error-correcting
| codes that beat it, but then both the transmission and
| reception become much more complex. (See FT8 for a currently
| popular weak-signal mode).
|
| I view Morse code radio contests much like a sail boat
| racing. Nobody moves containers of goods from China to LA on
| sail boats. But lots of people enjoy a good boat race on a
| sunny afternoon, and enjoy keeping the old marlin-spike
| seamanship skills alive. Likewise, ftp is a much smarter way
| to move a 3GB file from London to SF than using Morse code,
| but that doesn't mean that Morse code isn't good humor during
| a weekend radio contest.
| ianburrell wrote:
| One area Morse code is popular is using limited radios. Morse
| code works well with tiny (phone sized), low power radios.
| There is challenge called SOTA where hike to top of mountain
| and make contacts. It is much easier to take small radio and
| Morse paddle than the bigger radios needed for voice. There
| are low-power data modes, but then have to carry computer
| along and deal with software.
| uint8_t wrote:
| In absolute terms, probably, but some are declaring a
| renaissance associated with the increasing popularity in
| portable operation. Summits On The Air (SOTA) in particular
| favors lightweight transmitters. CW is such an efficient
| mode, in terms of speed, reach and circuit design that it is
| worth learning Morse for that single use case.
|
| Personally, once I gained some proficiency with CW I realized
| that it is an enjoyable pursuit in and of itself, so now
| while not climbing mountains I stay on the low parts of the
| band and exchange postcards with octogenarians and I couldn't
| be happier.
| irrational wrote:
| I got my license during the pandemic and it was not a
| requirement.
| teeray wrote:
| It's still very popular... tuning around CW portion of 40
| meters still yields plenty of stations. There's a fair number
| of enthusiasts in the Long Island CW Club [0] and CWOPS
| [1]--bith very welcoming groups committed to teaching CW.
| It's fun too--a bit like learning an instrument tbh. Learning
| it gives you access to very cheap, small, lightweight QRP
| (low-power) transcievers with great performance worldwide.
| It's also a useful skill when band conditions aren't as
| favorable.
|
| [0] https://longislandcwclub.org/ [1] https://cwops.org/
| jmclnx wrote:
| Nice, I hope people keep at it. And the low power radios
| sounds interesting.
| seabass-labrax wrote:
| It's still done in the UK, however you don't have to memorise
| anything. You're allowed to take a Morse code table into your
| examination, so most people don't consider 'learning' Morse
| code to be a requirement.
| karaterobot wrote:
| It makes me happy to know these guys are out there. I like that
| they've got a thing they care about and are dedicated to.
|
| Sounds like the ship this station communicates with, the S.S.
| Jeremiah O'Brien, is a restored Liberty ship used for day
| cruises. I'd love to know about the relationship between the
| (presumably) WWII naval history nerds who restored that ship and
| the Morse code nerds who operate this station.
| cylinder714 wrote:
| The S.S. Red Oak Victory, a Victory ship built in Richmond,
| California, is now a museum ship berthed near where it was
| built. Its radio room, operated by an amateur radio club, is
| open on Sundays.
|
| https://www.qsl.net/redoakarc/
| dayofthedaleks wrote:
| Nice to see reliable terrestrial radio services chugging along
| with orbital services becoming less assured.
|
| I was recently pleased to see eLORAN is gaining momentum to fill
| the void left by LORAN-C's shutdown in 2010. 8 meter resolution
| through radio triangulation is pretty impressive.
| jodrellblank wrote:
| Ignoring the Morse Code radio station, in the context of those
| banks of instruments and controls... each individual readout can
| be done cheaper and more reliably in software, but doing
| everything in software means one or two LCD screens.
|
| Will it ever be wall-sized banks of screens covered in eInk
| displays as standard industrial controls? Will it skip straight
| past that to Augmented Reality?
| ruined wrote:
| through-hole components and physical controls are standard,
| durable, and maintainable in a way that microelectronics will
| never be
|
| i see small touchscreens on devices where maintenance doesn't
| matter
|
| but if you need a complex bespoke interface that's durable and
| lasts for years, you will use a physical control surface made
| of off-the-shelf parts
| doubloon wrote:
| Had an interesting conversation with someone who used to run
| a radio shack and now works for one of the few remaining
| 'screwdriver shops' (PC shop).
|
| If I understood it, her theory was basically that radio shack
| wouldn't come back because the size of components nowadays is
| too small.
|
| And its funny you mention touchscreen. Because I bought a
| mechanical switch from her to do a DIY Mod on a 20 year old
| car. It was pretty simple and worked well. But this car also
| had a touch screen that was extremely anti-DIY friendly.
| These screens tend to get 'burnt' by the sun after 20+ years
| and stop working correctly. The typical fix for this screen
| is complete replacement or extremely complex repair via mail.
| Parts won't be available forever and the whole thing is
| closed source and incredibly hard to reverse engineer.
| WalterBright wrote:
| I patented a scheme where cell phones could communicate with
| morse code. The idea was to put a rocker switch on the phone, one
| side for dit and the other for dah. Then, you could text people
| without needing to look at the display. You could be texting
| people at a meeting with your hand in your pocket. The phone
| would convert the morse to text to transmit to your penpal.
|
| You could also opt to receive morse by having the phone vibrate
| in morse so you could stealthily receive texts, too!
| eastbound wrote:
| Cool. But the boss could subscribe too. Is it encrypted? Are
| there standards for morse code encryption?
| WalterBright wrote:
| The morse app would just convert it to/from text, and then
| the text would be sent by whatever app you would be
| keyboarding input to.
| nosrepa wrote:
| You can do that even now! Gboard has had Morse as an option for
| years.
| kqr wrote:
| But almost always with these things it's not iambic/semi-
| automatic, which it should be to be somewhat useful.
|
| I have been looking for morse code keyboards for smartphones
| and I have only found one that was good, and it was an early
| iPhone thing that hasn't worked on modern iPhones for years.
| davchana wrote:
| On older nokia phones un 2000-2004 (when I had them), I could
| text as long as I know I am on the typing screen. I knew
| pressing 2 three times gives you c, one 3 gives you D, #
| changes case, 0 gives you space. Two zeros gives you dot.
|
| I remember texting a lot while phone is under the table, or
| simply in pocket.
| bastawhiz wrote:
| This (T9) was incidentally a great accessibility feature for
| folks with limited vision. My mom is mostly blind and was
| able to text my brother and I without her giant magnifying
| glass, often faster than we could reply. Today, for better or
| worse, she largely uses speech to text.
| kqr wrote:
| What GP describes is not T9. The thing known as T9 is a
| predictive algorithm based on a compressed dictionary that
| generates words from single presses on each key. If you
| triple-tap 2 with T9 you get "cab", not C.
| bastawhiz wrote:
| I stand corrected on the name. My mom used what they
| described.
| chgs wrote:
| With normal pre t9, typing cab was a bit of a pain, 222
| _2_ 22 if I remember the "end of character" code right.
|
| It was more accurate than typifying on an iPhone with
| predictive text though.
| SoftTalker wrote:
| Yes and every middle- and high-school kid with a "dumb"
| cell phone could text without looking, holding the phone
| under the desk or in a coat pocket and using T9 code.
| neilv wrote:
| A related one-handed, eyes-off way to text fast is with the
| Twiddler chording keyboard, used by the wearable computing
| people, circa turn of the century:
|
| https://en.wikipedia.org/wiki/Twiddler
|
| Of course that, too, requires special training to use. And
| harder to integrate into a smartphone design than 2 side
| buttons. (Maybe turn the back of an iPhone-like form factor
| into a chording keypad, with physical buttons or some other
| tactile affordance?)
|
| Brad Rhodes at MIT would have a Twiddler in a pocket, a small
| Private Eye brand HUD on the corner of his hat brim, and a
| lunchbox-sized PC on a shoulder strap. He could be typing and
| looking up information while he was talking with someone or in
| a meeting, without them necessarily being able to tell.
|
| (Though, if someone did notice use of the wearable computer,
| they might not say anything anyway, since -- as he eventually
| realized -- some people who hadn't gotten the demo thought that
| the box with the cables coming out of it and going into
| clothing might be a medical device.)
| mech422 wrote:
| >>used by the wearable computing people, circa turn of the
| century
|
| One of the things they discovered, is voice command really
| wasn't suited to a wearable as it was distracting in
| meetings, susceptible to background noise, made you look like
| you were talking to yourself, etc.
|
| One of my favorite BoFH style stories was of someone that
| worked in an office where each PC was equipped with dragon
| naturally speaking. Apparently, you could walk thru the
| office yelling "format c:" <pause> "yes"....
| margalabargala wrote:
| You...patented this?
|
| Were you trying to ensure no one ever did this?
| WalterBright wrote:
| I patented a few things so I could be officially called an
| "inventor" ! I know, I know, the sin of pride.
|
| Here's a list: Patent 7831208 Wireless
| mobile phone having encoded data entry facilities
| Patent 7812993 Lossy method for compressing images and video
| Patent 7711748 Method and apparatus for simplified access to
| online services Patent 7028033 Method and apparatus
| for simplified access to online services Patent
| 6897977 Lossy method for compressing pictures and video
| Patent 6850782 Wireless device with vibrational communication
| capabilities Patent 6657647 Controlling the order in
| which content is displayed in a browser Patent
| 6418323 Wireless mobile phone with Morse code and related
| capabilities
|
| I could have patented many of D's innovative features, but
| chose not to. Many have been incorporated into other
| languages without attribution, but although that's a bit
| irritating I did sign up for that.
| chgs wrote:
| What prototypes did you build?
| WalterBright wrote:
| The startup I was with did some mockups.
| seabass-labrax wrote:
| You could consider joining the Open Innovation Network. Had
| you patented the D features and licensed them freely as a
| member of the OIN, in return, you'd effectively get
| immunity from patent claims against you from any companies
| who use the D language!
|
| [1]: https://openinventionnetwork.com/
| vijayr02 wrote:
| I call prior art - documentary link below:
|
| https://youtu.be/oye9AmOdsZc
|
| Watch from around 7:53 for around 1 minute.
| bigboy12 wrote:
| There's a vocal group who want to bring back the abacus.
| Sometimes you should just let go. .
| WWLink wrote:
| I always found it disappointing nobody tried making a phone
| with 5 programmable buttons on each side. It would make an
| excellent chording keyboard setup if the phone was narrow
| enough to grasp.
| WalterBright wrote:
| Much more efficient than the "tap code" prisoners re-invent.
| Retric wrote:
| POW's who knew more code still resorted to a new "tap code"
| because dot, dash, pause can't quickly be encoded with simple
| tap and pause.
| WalterBright wrote:
| Tap and scrape. Or taptap for dit, tap tap for dah.
| Retric wrote:
| I realize why you think this might work but understand
| people went with a new system for multiple reasons.
|
| First the goal is for the guards not to hear what your
| doing or just to hear seemingly random tapping. Scrape etc
| means your producing two different types and levels of
| noise making patterns more obvious and it's harder to
| control who can hear.
|
| Also what matters is time not the number of taps. One
| common encoding was 1 to 5 taps then pause followed by 1 to
| 5 taps and another pause for each letter thus averaging 6
| taps and two short pauses per letter. Morse code generally
| means 4 dots or dashes per letter so now you have 4 to 8
| taps ie ~6 taps, but far more pauses in alternate
| encodings.
| WalterBright wrote:
| I'm not sure the guards would be so stupid as to not know
| what the tapping means. It may be hard to tell where the
| tapping is coming from, though.
|
| > averaging 6 taps and two short pauses per letter
|
| This would be true if the letters are used with equal
| frequency. But they are not. Morse encoding uses short
| sequences for more common letters and longer ones for
| less common letters. For example, Morse E is dot, and T
| is dash.
|
| https://en.wikipedia.org/wiki/Morse_code#/media/File:Inte
| rna...
|
| For tap code, E is 5-1 and T is 4-4.
|
| https://www.inverse.com/article/11684-the-flash-and-tap-
| code...
|
| The advantage to tap code is it is easier to learn.
| Which, of course, also makes it easier for the screws to
| learn it and "tap" into those communications.
| Retric wrote:
| Moving which letters are the most frequency would help
| tap encoding but the much worse Morse encoding more than
| accounts for this.
|
| With tap encoding you need 1 unit for tap, 1 unit for
| pause between sections and 2 units for pauses between
| letters. Thus A is 1 + 1 + 1 + 2 = 5 units 2 letters take
| 6 units, 2 letters take 7 ... etc and only one Z takes
| sits at 5 + 1 + 5 + 2 = 13. (The exception is C and K
| share the same encoding at 1 + 1 + 3 + 2 = 7 units.)
| Average is ~9 units before considering letter frequency.
|
| For Morse the best you can do is tap and 1, 2, or 3 units
| of time for pauses. Let's assume tap takes 1 units.
| Pauses between dot's and dash are the most common pause
| so that's 1 unit. The pause between taps on a dash the
| next most common and uses 2 units, and the pause between
| letters is 3 units -1 because you don't need the short
| pause after a dot or dash.
|
| In effect a tap is 2 units (tap pause) dash is 5 units
| (tap, pause, pause, tap, pause) on it's own and every
| letter has a penalty of 2.
|
| So E is now easily beats tap encoding at 2 + 2 = 4, T is
| (5 + 2) = 7, but things get much worse, The reasonably
| common C is 5 + 2 + 5 + 2 + 2 = 16. With the worst case Q
| sitting in at an abysmal 5 + 5 + 2 + 5 + 2 = 19. And
| that's if you can keep all the taps and pauses strait, I
| would be shocked if most people could actually pull off Q
| most of the time.
|
| Feel free to do the time calculation on this sentence for
| each encoring, Morse code ends up far worse.
|
| PS: Did some editing in the first 16 minutes after
| posting.
| WalterBright wrote:
| > In effect a tap is 2 units (tap pause) dash is 5 units
| (tap, pause, pause, tap, pause) on it's own and every
| letter has a penalty of 2.
|
| See my other post in this thread about tap for dit and
| taptap for dah. This shortens the time. A dash would be 3
| units - tap tap pause, not 5.
|
| > I would be shocked if most people could actually pull
| off Q most of the time
|
| An experience Morse operator doesn't attempt to decode
| Morse. His brain is trained to shortcut it and the
| letters are formed automatically, just like a skilled
| piano player is not actually aware of his finger
| movements or the individual notes.
|
| I suggest tapping with a pencil to compare rather than
| trying a mathematical approach. Try SOS for example. I
| don't see a tap taking the same time as a pause. You can
| do a double tap in the same time period as a tap-pause
| easily enough. The tap itself doesn't take time.
| Retric wrote:
| Morse operators don't need to think about things because
| the sequences are so short and there's a rythim that
| keeps letters distinct. Abstractly dot dot dot with even
| spacing could be EEE or S but not EI or IE. Listing to
| longer messages makes the pause pattern clear, and you
| can even learn who's sending the message based on how
| they encode it.
|
| However, with SOS anyone can just dot dot dot, dash dash
| dash, dot dot dot longer pause on repeat and the message
| is clearly SOS not EEETTTEEE. That's why SOS was chosen
| it allows out of band communication of information. Even
| better triangulation adds location information allowing
| effectively anyone to say HELP I AM AT LAT X LONG Y.
|
| For a slightly less trivial sequence like
| HAMBURGERANDACOKE you very much need 3 distinct types of
| pauses to make things understandable. Further you really
| need to try communicating to someone else not just
| congratulating yourself after doing something simpler
| than average Morse code.
| WalterBright wrote:
| > you really need to try communicating to someone else
| not just congratulating yourself after doing something
| simpler than average Morse code.
|
| I didn't advocate something simpler than Morse, I wrote
| that Morse was more efficient than Tap. Nor did I
| "congratulate" myself. Your reply also seems answer
| points I did not make.
|
| SOS is also easy to remember without knowing full Morse.
| Retric wrote:
| > SOS is also easy to remember without knowing full
| Morse.
|
| It's not simply a question of memory. SOS and Morse are
| meaningfully different protocols.
|
| But I don't think I conveyed that bit particularly well.
| Try alternating between IAB, SOS, and IJS all are are dot
| dot dot dash dash dash dot dot dot. However, IAB and IJS
| is uses 3 different pauses not just 2. And that's before
| your tap morse code adds yet another type of pause.
| WalterBright wrote:
| P.S. After experimenting a bit, tap for dit and taptap for
| dash seems to work fine.
|
| For fun, get a pencil and tap SOS on your desk (or rattle
| your jewelry): tap tap tap taptap taptap
| taptap tap tap tap
|
| If you don't have a pencil, bang your cell phone instead!
|
| Hey, that gives me another inspiration. Don't need a rocker
| switch to enter Morse in your phone. Phones have an
| accelerometer, just bang the phone!
| kragen wrote:
| also a microphone
|
| if you like this, you might like 'magic boxes and secret
| knocks' https://www.mail-archive.com/kragen-
| tol@canonical.org/msg000...
| WalterBright wrote:
| I didn't think about the mike. Nice.
| kragen wrote:
| thanks! i had the advantage (?) of writing that before
| cellphones had accelerometers so i had to think up
| something else. haven't implemented it yet, tho
| kqr wrote:
| This is my annoyance when people talk about knocking in morse
| code. Though I suppose WalterBright in a sibling comment
| solved that handily.
| wrs wrote:
| This reminds me of the fantastic Connections Museum in Seattle
| [0] that maintains historical telephone switching equipment in
| (mostly) working condition with an all-volunteer staff. When I
| first visited, I was surprised to see that all the volunteers
| were about half the age I expected! You can see some of them on
| the YouTube channel [1].
|
| [0] https://www.telcomhistory.org/connections-museum-seattle/
|
| [1] https://youtube.com/@ConnectionsMuseum
| fnordpiglet wrote:
| Whenever I see this my joy is tempered by mourning for the loss
| of the living computer museum to accountants eating at the
| corpse of Paul Allen.
| oldnetguy wrote:
| The living computer museum was a great place to visit, but it
| is not the accounts eating away. It is his sister.
| wrs wrote:
| I'm with you! It was my dream to retire and become one of the
| old guys in lab coats repairing stuff at Living Computers.
| Maybe they'll get that sorted out and I'll still get a
| chance.
| fnordpiglet wrote:
| Not likely. As mentioned in a parallel comment it's
| partially that Jody Allen, his sister, doesn't value the
| geek culture in the least and partially that the owner,
| Vulcan, is run by MBA accountants that are finally
| unshackled by their eccentric nerd funder. Between them
| they're seeking to put the nerd passions of Allen to death
| and focus squarely on playing money managers. There appears
| to be little respecting of his legacy or wishes in his
| estate management and a lot of avarice.
| iamjaredwalters wrote:
| This has been an unexpected and enjoyable rabbit hole for me.
| Thanks for posting.
| whartung wrote:
| Does anyone know how the telegraph lines were architected?
|
| Did you have segments of shared stations, where a message sent
| from one station was echoed to all the connected stations, with
| one responsible for forwarding messages across segments?
|
| Just curious what the path of a message from, say, New York to
| Chicago was.
| dbcurtis wrote:
| You raise an interesting question, but note that this article
| is about KPH, a radio telegraph station, not land-line
| telegraphy.
|
| I don't know much about your actual question though.... I know
| that there were "repeaters" in the lines, basically a relay
| with a local battery, on longer lines. I know railroads had
| their own network of telegraph circuits between stations, with
| poles along the track right-of-way. I know that the first
| trans-Atlantic telegraph wires was what led to research into
| basic transmission line theory, since the first cables only
| allowed pitifully slow signalling and the reason why was not
| well understood.
|
| If you look at old photographs of rail road right-of-way, you
| see 6 or 8 wires or more, so they obviously were running
| multiple telegraph circuits along the line.
|
| In passing, I will note the trivia that land-line Morse (the
| original) and international radio-telegraph Morse is different
| in a few characters, because some of the character "clacks"
| become difficult to distinguish as "beeps" under noisy
| conditions.
|
| You have successfully nerd-sniped me today, well played.
| Animats wrote:
| For big operations such as Western Union, it was store and
| forward. Links were point to point links with messages hand-
| copied to paper at relay stations. Paper messages were sorted
| by hand, and re-sent by outgoing operators. Large buildings
| with large staffs were required.[1] KPH was such a relay
| station, where messages went from land lines to radio and back.
|
| Low-traffic lines and railroads tended to have many stations on
| one wire. Similarly, ships could talk to each other by radio.
| To get into the interconnected system, you had to go through a
| gateway to a commercial network, and there would be charges
| incurred at that point.
|
| [1]
| https://www.wondersofworldengineering.com/telegraph_office.h...
| cpeterso wrote:
| Some messages were sent through relays, or the lines could be
| tapped, I wonder if any telegraph operators encrypted their
| messages using a shared key.
| pjlegato wrote:
| Telegraphic ciphers and codes were common, both to save
| money through compression, and as it was well known that
| many people would be reading and re-transmitting the
| message as it worked its way through the system.
|
| There were various standardized codebooks published for
| when the message was not secret and compression was the
| only consideration:
|
| https://en.wikipedia.org/wiki/Commercial_code_(communicatio
| n...
|
| Frequent telegraph users with an additional need for
| secrecy, such as investment bankers, developed similar
| proprietary in-house codebooks.
| eszed wrote:
| If you're interested in this topic, here's a book to read:
|
| https://en.m.wikipedia.org/wiki/The_Victorian_Internet
|
| It's been twenty+ years since I last owned a copy, but it was
| one of my favorite books for a while. The bulk of the material
| is about pointing out amazing parallels between behaviors on
| the early internet and century-previous telegraph / wireless
| networks, but it also discusses physical and network protocols
| - not, perhaps, in huge depth (I don't remember exactly), but
| everything mentioned in sibling comments was familiar to me.
| Stratoscope wrote:
| Tangentially related, Hyundai has a nice little tribute to Morse
| code in their Ioniq 5 and 6.
|
| On the steering wheel, where they traditionally placed the
| stylized "H" Hyundai logo, there are just four dots:
|
| * * * *
|
| Which is Morse code for the letter "H"!
| JJMcJ wrote:
| The Jeremiah O'Brien, while docked in San Francisco, actually is
| in running order.
|
| Once in a while there are cruises around the Bay.
|
| It was at the 50th anniversary memorial for D-Day, steaming off
| the Normandy shore.
| sidewndr46 wrote:
| So I've tried to get aboard for a tour more than once, but from
| what I gather it's not really something you just casually do.
| When I called them (standing at the locked door) they said they
| just run tours whenever possible, which may or may not happen
| on any day. I'm assuming you need to know someone involved with
| the museum to get aboard.
| femto wrote:
| Morse code lives on in the form of Station Identification [1]. By
| law, radio stations are required to periodically transmit
| identifying information. The announcer on a commercial radio
| station will typically say it, but there are lots of Land Mobile
| Radio stations out there that don't have a person in the loop.
|
| For an unattended station, by far the cheapest and easiest thing
| to do is program the base station to periodically transmit the
| station ID as a burst of Morse code. It's not that many years
| since I wrote code to transmit Morse, that code being embedded in
| radio base stations that are still being sold.
|
| [1]
| https://en.wikipedia.org/wiki/Station_identification#Identif...
| lsh123 wrote:
| Same is true for aviation nav aids: VOR, ILS, ... stations
| transmit their name in Morse code for identification.
| larrysalibra wrote:
| Same is true for maritime racon navigation marks which
| transmit a morse code letter as identification in response to
| the reception of a radar pulse...the morse code is then
| visible on the radar display.
|
| We had to learn morse code for Hong Kong's "grade 1 pleasure
| vessel certificate of competency" -> a credential required to
| operate pleasure vessels greater than 15 meters in length.
|
| It's pretty easy to pick up and there are a few phone mobile
| phone apps that make learning morse code fun.
| firesteelrain wrote:
| Why do those pictures look like they were created with DALL-E?
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