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5

As a mode for communication, as you say, it's pretty redundant and inefficient. I've never heard of it being used seriously. Occasionally people might hold a morse code practice class and transmit the sound of morse code on a 2 m FM channel. Presumably because FM radios are what the students have, and perhaps they're not yet allowed to transmit on HF. This ...


3

Personally I wouldn't worry much about chirp (frequency pulling), unless it's really bad. It's not hard to copy, for a human anyway. It warms my heart whenever I work someone with a chirpy homebrew transmitter. Key clicks, what you're calling splatter, is another matter entirely. You'll need some sort of circuit to shape your keying envelope or your key ...


3

I took it apart and found a transistor that had been blown apart, pictured below (the black one with its metal innards showing), likely from a scenario described by @rclocher3. This is the NPN transistor that supplies voltage to the blue PNP transistor and should be switching based on its base input but instead is supplying a constant 5V. No surprise there, ...


3

My experienses on 2 meters when I was living in southern Finland (near Helsinki). My Finnisf call sign was (and still is) OH2AXE. I did not have 70 cm equipment. Antenna: 2 x 2 stack of double hybrid quads, gain about +12 dBd, about 10 m above ground. 50 W homemade linear amplifier. Most of the time the TX power is not so critical, even 5 or 10 W is enough ...


2

The SNP specs that I can find online say they can differentiate puffs shorter than 0.25 seconds, which should be good for use as a straight key at at least 5 wpm (maybe 3 to 5X slower than skilled hand keying). You’ll have to try one out to see if a trained wind instrument musician could operate one faster than these published numbers. Or if a sideswiper, ...


2

In the keyer, PNP transistor Q4 should be on when the keyer is supposed to be keyed. I assume that the transceiver's key jack goes to a CMOS high-impedance input and has a pull-up resistor, and that the key jack's sleeve terminal is tied to ground. If all that is correct, and if the keyer is working correctly, then the positive output of the terminal ...


2

Listening to your recording, some of the Morse characters aren't even legitimate for the US, e.g. ··––. The timing seems fairly regular, meaning that the characters seem formed by a machine and not by someone at a straight key, but the timing isn't quite correct. The tone is quite buzzy with square-wave-like harmonics. I'm just speculating blindly, but to ...


2

One significant advantage (probably the biggest one) of transmitting Morse as an AM tone rather than a simple carrier on-off is that the simplest radio receivers (crystal sets and other single-stage detectors) can receive AM, but can't hear a tone for true CW. This is because they don't have any internal oscillator -- these simple sets just rectify the ...


1

I have also looked for an FRS set with a CW/Morse button, […] but this seems nearly non-existent. The Family Radio Service has only limited provisions for digital data transmissions and it's likely that morse code audio transmissions (aka "MCW") wouldn't be considered that anyway. [Though this comment claims it would be fine. In that case, perhaps ...


1

Avoid modifying FRS radios I think that you should avoid modifying FRS radios. It is illegal, unless you want to build your own, go to the FCC, and spend a possibly large sum testing the radio, to make sure it complies with their rules. it would not be worth it anyway, since the FCC does not, to the best of my knowledge allow Morse on FRS. I think, that if ...


1

I believe FRS is the wrong place to look. Once you crack open that radio to hook up a telegraph key the Part 95 FCC certification is lost. MURS is another Part 95 service and it allows telegraphy, but not hand sent Morse code from the looks of it. Other comments and answers mention 27 MHz radios but I'm not so sure that they are CB radios. There's a few ...


1

When I was a kid in the seventies, I got a set of walkie-talkies for Christmas one year that each had a Morse code button. I think I had to press the PTT switch before pressing the Morse code button. I had memorized the Morse letters, for instance "A is dot-dash", and so had a few friends, but none of us had actually been taught how to send clean ...


1

When testing my speaker and volume knob(with music from my computer via audio cable), I the volume is too quiet. The line out on your computer is designed to drive the line in on some other equipment, not a speaker. The input impedance on a line input is typically around 10k ohms, and at maximum volume the voltage is around -10 dBV or 316 mV. This is simply ...


1

SNP keys have been built, and were apparently described in Mars 2004 QST. As I'm not a member of ARRL I can't access it, but the first page of the article can bee seen in the following video: https://www.youtube.com/watch?v=wsE-S2eXhK0 It says that "experienced users routinely reach 25 wpm or more", which could be interpreted as being comparable ...


1

There appear to be MIDI harmonica controller products, as well as keyer software that takes MIDI input. Probably designed from the start to be highly responsive to fast musical rhythms from air pressure change input. And with keyer software support already adapted. See: https://www.lekholminstruments.com


1

An SNP isn’t very fast at all*. If you’re okay with your mouth being “in use” perhaps a bite-actuated switch in place of (and configured the same as) a straight key would be better. You could “key” much faster that way, I’d bet. Just make absolutely sure to avoid RF burns in the mouth. :-) Prototype could be as simple as some contacts and wires on the “open” ...


1

I found a comment on the web that the U.S. Army used 641 Hz for their radio operator Morse Code training.


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