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Loggings => 22 Meter Band HiFER Beacons => Topic started by: Dave Richards on April 15, 2018, 1835 UTC

Title: Question About Morse Code Speed for Beacon "BRS"
Post by: Dave Richards on April 15, 2018, 1835 UTC
Hello there, fellow HiFERs. I'm very happy to see a dedicated HiFER section on these forums.

I am scratch-building a little beacon that will put out about 2mW into a horizontal dipole on top of my property fence, at about 7 feet above ground. It will be a bit of a cloud-warmer, I think, but I'm interested to see how it will get out. It will be powered by a single small solar panel with no batteries, so will be operational during daylight hours only. I hope I won't be missing the valuable grey-line propagation time with this approach, but we'll see how it goes. It should be on the air sometime this week. As it sits on the bench, it is coming up on around 13556.91 or thereabouts.

My question to the group is what you think an ideal code speed is? I want it to be fast enough to be copyable to the ear, so no QRSS. I have a personal preference for something around 10 - 12wpm, as anything slower bores me somewhat. However, I want the decision to be driven by what is most likely to be copyable to listeners struggling with what will almost certainly be a very weak signal. The beacon's callsign will be BRS, in honor of my neighbor's cat Boris.

I'm thinking that a relatively high speed would maximize the chance of copying the entire callsign before any fading takes the signal out, so I'm veering towards around 10wpm. What do you guys think?
Title: Re: Question About Morse Code Speed for Beacon "BRS"
Post by: Σ on April 15, 2018, 2151 UTC
Around 10-15 wpm is a good compromise. A lot of beacon hunters use SDR so the can easily see the CW on screen as well as hear it. I copy CW much better using two of my senses.

I enjoy your blog, btw.  😁
Title: Re: Question About Morse Code Speed for Beacon "BRS"
Post by: Dag on April 16, 2018, 0128 UTC
I have two HIFER beacons on 22m: one is slow speed frequency shift keying CW  (FSKCW4), where each dit is 4 seconds long, and another in slow speed CW (QRSS3) where each dit is 3 seconds long.  Each transmits "FL" identifier.

The reason for the slow speeds is because low power beacons (<2 mW) will be likely very hard to copy by ear unless the propagation is spectacular, and we won't have decent HF conditions for years to come. We haven't even hit the bottom of our current solar cycle yet and there's been a number of sun-spotless days this year.  Copying HIFER beacons is mostly due to software like ARGO where you can actually see the signal on the waterfall.

So, for those two reasons (very low power and poor propagation until the sunspots return), if you are going to run QRPp CW on 22 meters, my suggestion is to slow it way down to about 5-7 WPM. This allows for ear copy if conditions allow, and copy by ARGO software if conditions are poor.

Good luck with it!
Title: Re: Question About Morse Code Speed for Beacon "BRS"
Post by: Dave Richards on April 16, 2018, 1118 UTC
Thanks for the input, Σ and Dag - and thanks for the kind words on my blog, Σ. This little beacon will probably get a write-up. I also built a little temperature beacon, which will get written up first. It's a neat little device that outputs the current temperature as Morse code on the HiFER band. I liked the circuit, and got to wondering if I could build it as a simple beacon. Dag - using QRSS speeds for both your FSK and CW is a good choice. Even at the maximum radiated field strength allowed on this band, we're still talking about very low power levels. I use 4.6mW into a dipole as my standard, as calculated by W1TAG.

I ran it into a 50 ohm resistor this afternoon and put it on the scope. Peak-peak voltage into 50 ohms is only around 0.6 - 0.7V, so it looks as if the RF power out is only about 1mW. This could turn out be more challenging than I had thought.

I think I'll start out using ~5wpm and go from there. It sure will be great when the sunspots return. Perhaps I should say "if", but I want to be optimistic about this. The thought of spending the rest of my life in a repeat of the Maunder Minimum isn't very inspiring!
Title: Re: Question About Morse Code Speed for Beacon "BRS"
Post by: Σ on April 16, 2018, 1206 UTC
During the day you'd be surprised how well these flea powered beacons are heard. Conditions lately have been poor but on some days I've heard up to six HIFERs within an hour or so all running "normal" CW speeds. Half the fun is seeing some CW poke its head out of the noise and you need to spend some time trying to copy the whole 2 or 3 letter call.
Title: Re: Question About Morse Code Speed for Beacon "BRS"
Post by: Ed H on April 20, 2018, 1829 UTC
PVC runs about 10 WPM using a K1EL keyer, and has received several reports over the years from member tesla in Colorado. Antenna is a sloping dipole supported from a mast on the roof, the top of which is around 18 ft from roof level. This leaves the dipole ends still well clear of the roof.

We're just across "The Bay", so I'd hope you can get similar results at least, if you can clear the hills to your East.

Best of luck, and I'll keep an ear out.

Title: Re: Question About Morse Code Speed for Beacon "BRS"
Post by: Dave Richards on April 21, 2018, 1920 UTC
Thanks for the info and encouragement Ed. Space for antennas is limited here, due to my living situation, but this beacon project has already taught me a few things. A couple of good lessons have already been learned, and I am currently leaning towards not putting it on the air. It will most likely be the subject of a blog post though. I will provide a link to it in this thread if and when that happens.

The two things I have learned so far are -

1) I am hopelessly behind the times in continuing to use 78L05 regulators. I had a small stash of them, so was blindly using them, without considering alternatives. However, the 4mA quiescent current and ~2V dropout voltage was a needless drain on a little beacon that only draws ~3mA on key-down and is intended to run solely from a small solar panel with no battery. I have finally put in an order for some more modern LP2950 regulators, which have a quiescent current of <0.1mA and much smaller voltage overhead of ~0.1V.

2) The ATtiny 85 which keys the oscillator was not starting up properly in the mornings when the sun came up. I think this was because I had the BOD (brown-out detection) set to 1.8V. At that low voltage level, the small panel wasn't supplying enough current to power the beacon properly. The remedy was to burn the fuses on the chip again and increase the BOD to 2.7V, which seems to have cured that problem. Another cure would be to simply include a battery in the circuit that is powered from the panel.

Anyway, I'll link to my blog post when this particular learning experience is over. Thank you for your help and comments.
Title: Re: Question About Morse Code Speed for Beacon "BRS"
Post by: Ed H on April 23, 2018, 2057 UTC
Interesting stuff.

I should have given more consideration to efficiency with my beacon. Wanting to put something on the air without too much design effort (time), I chose to buy a 20 m QRP transmitter kit from Vectronics. Of course, even this is too "QRO" for Part 15 HiFER work, so an attenuator was designed to reduce the 1.25 W to the mW range. It works, but is wasteful, and modification is planned. I also need to integrate the keyer to run off the same supply as the transmitter (probably using a 7805...)

Nor was I that impressed by the Vectronics experience. I had trouble ordering the kit with a case, and when that was resolved and finally arrived, the "Attractive plastic adhesive faceplate" was a cheap paper sticker with the controls completely mis-labelled. Hmmm.

But... it does work, and in the enthusiasm of getting something on the air, the details were happily overlooked.

Good luck - and I look forward to reading more.