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Linux Kernel security developer, working for Microsoft. Also W7TXT. Views are my own.
Topics: #Linux #kernel #security, #amateurradio, #RF, #hamradio, #electronics, #science, #radioastronomy, #physics, #space, #arduino.

📡 https://w7txt.net/
🐧 https://blog.namei.org/
☠️ https://www.facebook.com/w7txt
jmorris

James Morris

Reply to @va3db@mastodon.radio
@va3db @n8dmt FWIW, I have had good RF experiences with the Samlex units made for radios, and MeanWell modular units for use inside project boxes.
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jmorris

James Morris

Reply to @ftg@mastodon.radio
@ftg No. This will eventually fail and fall off, probably while driving down the highway.
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jmorris

James Morris

@mossmann very cool: measuring < 0.01 Hz changes in an 60 kHz signal from Colorado while flying in a passenger jet is impressive.

RE: https://mastodon.social/@mossmann/115493045854686572
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jmorris

James Morris

AI really is no fun.
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jmorris

James Morris

Reply to @pathunstrom@ngmx.com
@pathunstrom yes.
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jmorris

James Morris

Reply to @MW1CFN@mastodon.radio
@MW1CFN Thanks, some great info there!
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jmorris

James Morris

Reply to @analgesicsleep@mastodon.social
@analgesicsleep Misleading advertising!
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jmorris

James Morris

Reply to @K4NE@mastodon.hams.social
@K4NE It's the Andonstar AD246S-M, which was recommended to me by another microwaver. Has HDMI out, and a smaller installed screen, which is probably right for me.
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jmorris

James Morris

@jbz who needs Black Mirror?

RE: https://indieweb.social/@jbz/115435878385867328
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jmorris

James Morris

Reply to @MW1CFN@mastodon.radio
@MW1CFN yes, indeed, it's on my list of things to try. A couple of years ago I noticed a station in NZ was able to copy some very weak signals from me and it turned out they were using a Wellbrook receiving loop. By the time I wanted to then buy one, they went out of business and I just missed their final sale. I do need to be able to transmit, so not quite the end of the world.

Loops seem to be a reasonable option for vehicle mounted HF as well. They may look ungainly but so does everything if you want to cover 3-30 MHz.
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jmorris

James Morris

I finally bought a USB microscope and wow does it help with reverse engineering RF circuits. Quite an interesting & surreal world down there, too. This is from a 60 GHz wireless backhaul device. The RF wavelength is about 4.5mm.
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jmorris

James Morris

Reply to @touk@smores.town
@touk get out
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jmorris

James Morris

Reply to @MW1CFN@mastodon.radio
@MW1CFN you have an amazingly quiet QTH! I get S9 noise on many HF bands and I'm often shocked to see ~zero noise when portable. Could be I need better grounding & setup, too.
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jmorris

James Morris

@andersonc0d3 congrats! Good to see bugfixes with the reporting.

RE: https://infosec.exchange/@andersonc0d3/115419629407280002
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jmorris

James Morris

I gave a talk on generating millimeter-wave signals from 122-141 GHz at Microwave Update on the weekend.

https://microwaveupdate.org

Here are the slides: https://w7txt.net/wp-content/uploads/2025/10/A-Synthesized-F-Band-Signal-Source-for-122-and-134-GHz-v1.pdf
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jmorris

James Morris

Large discone antenna in Arizona, covers 3-30 MHz. Licensed amateur operators can use this, at the Titan Missile Museum. I didn’t have a radio with me.
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jmorris

James Morris

Reply to @MW1CFN@mastodon.radio
@MW1CFN would be interesting to measure the background noise at each location, too.
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jmorris

James Morris

Reply to @W6KME@mastodon.radio
@czarbucks @amyedge @ai6yr @lckrohjr @AE4WX @Jennifer @BakerRL75 @firefly @W6KME how are you using ax.25 ?
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jmorris

James Morris

Reply to @MW1CFN@mastodon.radio
@MW1CFN very nice! Sounds like an efficient setup for reaching all skip angles in all directions.
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jmorris

James Morris

WSPR and Red Bull for breakfast in Eastern WA.
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