Reminds me of an old coworker, who I think had some sort of paranoia or persecution complex, because he always had stories of how his mouse would stop working at random and cite the kinds of EM pulses that could be used to cause such an effect, clearly the work of someone who wanted to harass him
Seen that with an elevator running. As soon as the elevator moved, wifi & BT died.
The problem was that the elevator was older than wifi and BT, so there was no warranty or something they could just call on. I told them to still get it fixed, as the local equivalent of the FCC is known not be be that nice when something is creating problems on the spectrum.
My neighbor’s poorly shielded microwave would knock out our WiFi. Because microwaves are in the 2.4GHz range, which is also the same range as older WiFi. Except that a microwave operates with several thousand times more power than WiFi, so it essentially acts as a jammer when it’s not shielded well.
Figuring that out took me fucking ages. I eventually heard her microwave beep through the shared wall, right as my WiFi came back online.
Yep, microwaves are nasty in that regard.
It’s truly a challenge when even your elevator is on the spectrum.
Me trying to find out why I hear static on my ham radio.
Some decades ago when I was still an engineering student, my team had to present an electronic assignment. The damn circuit didn’t work, no matter what I did. So I decided to go ask the teacher for advice. I walked away a couple of meters, when my teammates told me that the circuit finally started working. As soon as I went back, it failed again. We soon determined that it failed only when I was near it. My teammates presented the assignment while I was at the other side of the lab. We passed the assignment, and sure enough, when I approached again to pick up my things, the damn circuit stopped working again.
https://catb.org/jargon/html/magic-story.html
A Story About ‘Magic’
Some years ago, I (GLS) was snooping around in the cabinets that housed the MIT AI Lab’s PDP-10, and noticed a little switch glued to the frame of one cabinet. It was obviously a homebrew job, added by one of the lab’s hardware hackers (no one knows who).
You don’t touch an unknown switch on a computer without knowing what it does, because you might crash the computer. The switch was labeled in a most unhelpful way. It had two positions, and scrawled in pencil on the metal switch body were the words ‘magic’ and ‘more magic’. The switch was in the ‘more magic’ position.
I called another hacker over to look at it. He had never seen the switch before either. Closer examination revealed that the switch had only one wire running to it! The other end of the wire did disappear into the maze of wires inside the computer, but it’s a basic fact of electricity that a switch can’t do anything unless there are two wires connected to it. This switch had a wire connected on one side and no wire on its other side.
It was clear that this switch was someone’s idea of a silly joke. Convinced by our reasoning that the switch was inoperative, we flipped it. The computer instantly crashed.
Imagine our utter astonishment. We wrote it off as coincidence, but nevertheless restored the switch to the ‘more magic’ position before reviving the computer.
A year later, I told this story to yet another hacker, David Moon as I recall. He clearly doubted my sanity, or suspected me of a supernatural belief in the power of this switch, or perhaps thought I was fooling him with a bogus saga. To prove it to him, I showed him the very switch, still glued to the cabinet frame with only one wire connected to it, still in the ‘more magic’ position. We scrutinized the switch and its lone connection, and found that the other end of the wire, though connected to the computer wiring, was connected to a ground pin. That clearly made the switch doubly useless: not only was it electrically nonoperative, but it was connected to a place that couldn’t affect anything anyway. So we flipped the switch.
The computer promptly crashed.
This time we ran for Richard Greenblatt, a long-time MIT hacker, who was close at hand. He had never noticed the switch before, either. He inspected it, concluded it was useless, got some diagonal cutters and diked it out. We then revived the computer and it has run fine ever since.
We still don’t know how the switch crashed the machine. There is a theory that some circuit near the ground pin was marginal, and flipping the switch changed the electrical capacitance enough to upset the circuit as millionth-of-a-second pulses went through it. But we’ll never know for sure; all we can really say is that the switch was magic.
I still have that switch in my basement. Maybe I’m silly, but I usually keep it set on ‘more magic’.
1994: Another explanation of this story has since been offered. Note that the switch body was metal. Suppose that the non-connected side of the switch was connected to the switch body (usually the body is connected to a separate earth lug, but there are exceptions). The body is connected to the computer case, which is, presumably, grounded. Now the circuit ground within the machine isn’t necessarily at the same potential as the case ground, so flipping the switch connected the circuit ground to the case ground, causing a voltage drop/jump which reset the machine. This was probably discovered by someone who found out the hard way that there was a potential difference between the two, and who then wired in the switch as a joke.
Your capacitance is probably weird. Are FM radios you tuned also very likely to go to static when you walk away? (also possible the cause was something you were wearing or carrying)
maybe you wore something that gave you just enough static charge to cause problems?
My old keyboard had an identical problem to this. I would play games with my friends, and randomly it would just cut out for like 1 second. When it first started I thought it was just me getting old and fudging my key presses, but suddenly one day, I realised it was my office fridge that had turned on.
I’ve had a couple of issues like this:
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Wireless mouse has a flaky connection. Turns out the issue was the USB port it was plugged into (probably RF interference as other devices worked fine on that port)
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We had a couple of radio receivers in a server rack. The scale of the project had shrunk over the years, so what used to fill up 2 racks now only half filled them (mostly because of upgraded components becoming faster and smaller over the years). Another project needed needed some rackspace, so we reracked everything into a single rack. When we were done, we found that one of our receivers couldn’t get a signal, and another would lose it regularly. Checked over all of our connections and the antennas, but everything seemed normal. Turns out something in the other project was blasting out RF interference.
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We would occasionally need to manually move data on/off a server using a USB2.0 hard drive. This worked fine for years, until one day we had a server that would randomly disconnect from the drive a few seconds into the transfer. Tried different ports, same issue. The drive itself worked with all the others, so we decided the issue must be with the server. We swapped it out for a brand new one with plans to send the old one back for warranty repairs. Except the new one has the exact same issue. Both servers came from a newish batch from the OEM. Turns out that the earlier versions had a hardware “bug” where the USB ports would source more than the 500ma allowed by the spec. Since they fixed that, our drive would trigger the current limit during sustained use and temporarily depower the port. Solution: get a USB Y cable and power provider power from a wall block
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I had a mouse that would double click (or more) when you pushed the button. This was pretty obviously a hardware issue, but I figured I could just tell the computer to ignore double clicks that happened “too fast” and avoid needing a new mouse. In theory that should have worked, but the input stack on Linux turned out to be a giant web that I couldn’t figure out, so I ended up opening the mouse and soldering on a random capacitor I had lieing around.
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recently dealt with an issue at my parents house where whenever they connected the TV to the wifi, half the devices in the house would lose connection. turns out there was an instability in the Comcast router firmware and whenever the TV would connect it would crash everything else on the 2.4ghz frequency.
solution was to replace the router with one they owned instead of whatever crap they were leasing from Comcast.
I had an issue like this with a tp-link Wi-Fi adapter in my computer. Never buying from tp-link again
"Computer works fine now, but the smell of decomp is becoming unbearable… "
Reminds me of the story of a company whose internet connection would cut out intermittently and they couldn’t figure out why. Details hazy but the gist is here.
One day they have a tech come in to investigate the problem. He goes downstairs to where the router is, and everything’s fine.
Seemingly the moment he goes to leave, the connection goes off. Panic stations! He goes back to the router and the connection is re-establishing. OK. All tests fine. He goes away again. It goes off again. What. Tech aura is real!
Nope. Turns out that when he went downstairs, he used the stairs. When he was coming back up he was lazy and used the lift.
The lift motor had been causing enough EM noise to knock out the connection whenever it was used.
My keyboard and mouse disconnected for a second everytime I sat on my chair. I have changed my laptop recently and I haven’t been able to reproduce this behaviour.
USB-3 over USB-A upstream sockets often put out 2.4GHz noise which will interfere with many wireless dongles, including those commonly used for wireless mice and keyboards. The solution is to get a USB2 extension cable or hub for your dongles.
Intel knew this would be a problem, but ignored it.
In the core2duo era I overclocked a cpu to 2.4GHz, and It killed the wifi in the computer similarly, it took a while to figure out why it was happening, and connect the 2 seemingly unrelated thing.
Microwave ovens also work in the 2.4 GHz range, at one flat my torrents basically stopped when my neighbor used their oven.
I used to have a hard drive dock that would knock the wireless powerline adapter network out whenever it was turned off
This is like the tech equivalent of consulting the village shaman or wisewoman for some serious disease.
Pumps and motors do mess with electronics though.
True, true… The techpriest vibes I’m getting out of this is because it’s a minor to non-existant improvement that might or might not be placebo is achieved by seemingly outlandish cure. As if the angry spirit of the fridge needed appeasing so that it stops haunting your mouse.
especially if the pseudo-solution does work in terms of eliminating the symptom, but the real problem was that something isn’t grounded properly…
Ive had commercial techs float the idea of wrapping a tv reciever in foil to mitigate signal interference.
The shamans gut feelings are to be listened to.
I worked for a cable company as the sysadmin. They were having trouble with channels going off randomly but most often in the morning and evening. One day in the middle of the day I’m out there with all hands on deck discussing the problem when one of the employee’s showed up in his older GM truck. Just as he arrived the channels went out and they jumped on the scopes and cable meters to start looking for the problem. He got out it stopped. We all stood around for a few minutes saying it was going to be a long day if we couldn’t figure this out. After a little bit he was instructed to go back to burying drops on his schedule. The second he cranked up the problem started. He drove off and it stopped. Three of us just looked at one another and we called him back. Sure enough as soon as he drove up the problem started. He was given instruction to not drive past the office gate and the problem went away. As to what on that old truck was throwing out all the gigahertz interference we may never know. That truck was gone withing a week.
I can’t say if the frequency is right, but poorly shielded spark plug wires will send all kinds of EM out. You know, the older cars where if you touched one of those wires you’d feel it, or you could see the aura if it was dark jumping around.
This reminds me of when I had apprenticeship classes that got interrupted by the covid lockdowns. I was forced to do theory classes online over zoom. Every morning my wifi connection would drop for a few minutes at a time during my classes.
Turns out it was the microwave. Every time someone used the microwave, it would disrupt the wifi/router for the whole house.
Ended up making a sign to let people know I was in class. My classes were only for 8 weeks total. I had about 4 or 5 weeks remaining by the time I figured it out so it wasn’t too long of an inconvenience.
I’ve seen similar. Whole two story office building’s wifi got knocked out by some big ol’ 1960s microwave.
No one could figure out why the wifi kept going down during lunch.
