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QRP FUN
Apr 24, 2019 2:10:24 GMT
via mobile
Post by Admin on Apr 24, 2019 2:10:24 GMT
Not Part 15 but low power fun. I'm a Ham radio operator and haven't had time lately to make any contacts.
Tonight though I got on my MFJ-CUB CW 20 meter radio. About 2 watts into a ground mounted vertical antenna. This radio is the size of a small portable radio.
I made a couple CQ calls. No answer. So I tuned around and heard a weak station calling CQ. I called back and we connected.
The station in Florida was also low power, same as me. I'm in Northern Ohio. We exchanged name, location, signal reports and quick comments as you never know how long you'll be able to hear each other.
In all, about 15 minutes but amazing and fun to do it with such a simple setup. I'm ready to do more of this and since I'll retire next week, I'll finally have the time...
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Post by Boomer on Apr 24, 2019 3:53:33 GMT
QRP, the art of low power
I always like to hear how much can be done with low power, QRP, on all kinds of bands, from longwave to 2.4 ghz wi-fi, though I don't know how much skip can happen up at the higher end there.
It should be noted that there are also some frequencies on shortwave where Part-15 can be used, like 13.56 mhz, the most well known.
I hope you can do good works with your retired time, and being retired will lighten the load somewhat. Maybe you could program MRAM more, or get your carrier current rig back up.
Nice contact there though, maybe we're heading towards the sunspot peak again.
Boomer
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Post by thelegacy on Apr 24, 2019 15:57:59 GMT
I do wish there was a good AM transmitter for 13.560 and maybe C-Quam. I can't remember how many mW's your allowed that could make or break you. More than 100 mW and the signal could go 2 miles local and maybe DX if the band was open.
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Post by mark on Apr 24, 2019 23:15:57 GMT
@ Admin,
Happy retirement, and a good time to retire at that. The weather is just getting nice now.
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Post by Boomer on Apr 25, 2019 4:13:03 GMT
E-bay has had some 13.56 transmitters available, I think they were being sold out of Cypress? They're simple units in a black box, with power, audio and antenna, and maybe a volume control for the modulation.
The circuit is really simple, with about 12 parts, I saw the innards of the thing somewhere, sorry I'm not more researched, but that was a year ago.
The circuit looked like a one transistor crystal oscillator, with a one transistor modulator. That's all you need, since the power you need is low, it's said to be 2 milliwatts into a half wave dipole for the frequency, and it goes by signal strength at a specified distance. In a way that's good, because you could use a shorter vertical whip antenna with more power going into it, to reach the specified field strength.
I believe that range is 2-5 miles local, with skip outside the area, which is always possible. I got parts for my own rig, but haven't built anything yet.
Boomer
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Post by Boomer on Jul 19, 2019 17:07:22 GMT
You might like this Bob, for QRP (low power). Hope you're around, but if you're in Hawaii right now, I wouldn't blame you for relaxing in your retirement. Hang loose!
I know you live in Ohio, so I thought about this post for that reason too. I was listening to a web radio, and tuned to the frequency of 1620 because it was one channel that seemed to be the clearest.
There wasn't much there, but a signal was fading in and out, and I could hear a few words at a time. I heard 'Mentor' and 'Cleveland' and it had that narrow quality of a Traveler's Info Station, voice quality audio.
Looking it up, indeed there's a TIS station in Mentor OH, up by Lake Erie. The web radio was located over 150 miles away, and the time was about a half hour before dark.
I've calculated a TIS station's power output as being well under 1 watt, maybe a few hundred milliwatts, with a max local range about 3.5 miles, so that's some impressive QRP there to hear it skip 150!
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QRP FUN
Jul 21, 2019 6:38:52 GMT
via mobile
Post by thelegacy on Jul 21, 2019 6:38:52 GMT
This was something I brought up a long time ago that a few hundred milliwatts could possibly skywave even on the medium wave and.
Thanks for bringing that one up I find it very interesting.
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Post by Druid Hills Radio on Jul 22, 2019 12:59:13 GMT
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Post by Boomer on Jul 24, 2019 1:13:25 GMT
The Youkits casing looks a lot like what are used to house hobby FM transmitters too! Must be a common case, black extruded aluminum body with end panels. I should see if they're available for projects that I might make.
Boomer
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