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Car allergic to vanilla ice cream (2000)

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Re: Car allergic to vanilla ice cream (2000)

#461

Post by jonhohle »

midoridensha wrote: post #409
jonhohle wrote: post #222

Earlier quoted context omitted.

When it’s sunny, my wife’s car can’t open the garage door, and my car requires getting extremely close. Once the sun goes down, we can both open the door from the street. It turns out our solar panels (or the optimizers, or the inverter) emit radio frequencies that interfere with our garage door opener. When the sun is out and they are producing energy, the interference is stronger than the homelink garage door opene…

How old is the garage door opener? Older ones used frequencies that are more susceptible to interference from certain sources. It's possible to buy new receivers to connect to your existing door opener.

The garage door openers aren’t terribly old, but they are terrible!

I have a HomeKit opener attached to it that we use during the day. Fortunately that’s been reliable enough to get around the issue.

Re: Car allergic to vanilla ice cream (2000)

#462

Post by jonhohle »

_whiteCaps_ wrote: post #248
jonhohle wrote: post #222

Earlier quoted context omitted.

When it’s sunny, my wife’s car can’t open the garage door, and my car requires getting extremely close. Once the sun goes down, we can both open the door from the street. It turns out our solar panels (or the optimizers, or the inverter) emit radio frequencies that interfere with our garage door opener. When the sun is out and they are producing energy, the interference is stronger than the homelink garage door opene…

Some clip on ferrites on the inverter cables might help. If you have any amateur radio neighbours they'd probably love to help you with a project like this.

On the cables coming in from the panels or wiring going back to the main panel?

Re: Car allergic to vanilla ice cream (2000)

#463

Post by jonhohle »

djmips wrote: post #237
jonhohle wrote: post #222

Earlier quoted context omitted.

When it’s sunny, my wife’s car can’t open the garage door, and my car requires getting extremely close. Once the sun goes down, we can both open the door from the street. It turns out our solar panels (or the optimizers, or the inverter) emit radio frequencies that interfere with our garage door opener. When the sun is out and they are producing energy, the interference is stronger than the homelink garage door opene…

Just curious but did you try any bodged shielding?

I used a coax cable to move the antenna closer to the exterior wall and didn’t see an improvement, however, I might not have grounded the shielding properly. I’ve had to replace the control board since then and didn’t replace the antenna on the new board, but may try that again.

Re: Car allergic to vanilla ice cream (2000)

#464

Post by doloputer »

ciabattabread wrote: post #375
Animats wrote: post #227

Earlier quoted context omitted.

Telcos used to monitor their copper outside plant for moisture. This was called Automatic Line Insulation Testing in the Bell System. The ALIT system ran in the hours before dawn. It would connect to each idle line, and apply, for tens of milliseconds, about 400 volts limited to very low current between the two wires, and between each wire and ground, measuring the leakage current. This would detect moisture in the c…

Ah, so that's why there were always nitrogen tanks on NYC sidewalks.

Yup, here's a tom scott video on the very same: https://www.youtube.com/watch?v=juZqGU9iuq0

Re: Car allergic to vanilla ice cream (2000)

#465

Post by I_Am_Nous »

bombcar wrote: post #272
addaon wrote: post #126

Earlier quoted context omitted.

Alternators aren't needed for starting. Perhaps a similar issue with the starter motor? But even then you'd hear the thunk of the starter solenoid. Any audible clue definitely makes root-causing simpler.

I have a crank sensor that is going out, and though it still works most of the time if the crankshaft stops in just the right position it becomes an absolute bear to start, and runs in limp mode when it does. Any of the other positions it works just fine.

This reminds me of an old F250 my dad had. He towed it from Colorado to Missouri and about halfway he noticed his gas mileage got worse. But, you know, coasting down mountains until you get to plains would also have a similar outcome, so he didn't think about it.

Once he got to Missouri he noticed the transfer case (I think) had somehow bounced out of neutral and was partially engaged, which chewed many teeth off the flywheel. To start it we had to get a pipe wrench and manually rotate the flywheel to a spot with enough teeth to catch the starter and turn over. That got harder and harder (as it kept chewing off more teeth) so eventually we had to push start it and pop the clutch. Thankfully it was a manual so it still worked!

Re: Car allergic to vanilla ice cream (2000)

#466

Post by Paul-Craft »

K7PJP wrote: post #398
mrguyorama wrote: post #309

Earlier quoted context omitted.

I thought the apple "lift and drop the computer" story was about the Apple 3. It had no vents, so it was always overheating and "unseating chips" like the Xbox 360 heat issues. https://en.wikipedia.org/wiki/Apple_III#Design_flaws And so it doesn't become apocryphal but stays a real story, there 100% were people who "Fixed" their RRoD Xbox 360s by wrapping them in towels for an hour so they cooked themselves even more…

I've got an HP Laser Printer from about 15 years or so. About once a year, the printer stops responding and I have to remove the board, put it in the oven for 10 minutes or so to revive it.

What even is the theory on how that could possibly work? I believe you, it's just that I don't have any mental model of how baking a circuit board makes it work right for a year, and how it keeps working to fix the issue.

Re: Car allergic to vanilla ice cream (2000)

#467

Post by orbital-decay »

mschuster91 wrote: post #457
liotier wrote: post #433

Earlier quoted context omitted.

A customer's DSL connection dysfunctioned every evening during December - but worked fine the rest of the year... Culprit: interference from nearby Christmas decorations leaking EM all over the place. A customer's DSL connection dysfunction's frequency increased mornings and evenings. Culprit: the lift's electric motor leaking EM all over the place. A bunch of DSL connections degrade when traffic increase... Crosstal…

It's not like fiber doesn't have its own weird failure modes. Favourite one I heard was shoddy belowground work while crossing a street. No problem with ordinary car traffic, but heavy trash haul trucks could interrupt the link.

An ISP my friend worked at was having weird outages in one area, and it turned out that they had an apartment block built right in the way of their free-space optical link. Surprisingly, it was fine at first because the link went straight through it without obstructions, window to window. But when they started to add window panes, finishing the construction, the link became spotty, and adding the doors blocked the signal completely.

Re: Car allergic to vanilla ice cream (2000)

#468

Post by AdamJacobMuller »

xenadu02 wrote: post #155
pixl97 wrote: post #75

Earlier quoted context omitted.

I had a truck do this kind of behavior once. Finally figured it out after months when I moved a wire and it started, then move the wire close to another wire and it would no longer start. These were wires that would typically be close, so my guess is one of the wires was now generating enough noise that it was bleeding over into some other system and causing it to fail. As the car bounced around the proximity of the…

EMF can do some seemingly crazy things. I built a kiln controller and the initial version would sometimes randomly lockup, reboot in the middle of an operation, or do other seemingly "crazy" things. Sometimes even the hardware watchdog would stop functioning. Turns out contactors pulling in and out a 5000w load generates some strong EMF and sometimes that EMF is enough to cause random glitches to the CPU or other har…

EMF is fun.

We had one access point (unifi) in our datacenter which was consistently failing.

fail, RMA, fail, RMA, probably replaced that thing 5 times. It was also incredibly unreliable.

Meanwhile all the other access points (probably 10 of them in total) had 0 issues.

Eventually realized that the cable for that AP was running perpendicularly over the conduits which fed power into our suite, so, about 1MW of power. Relocated the cable so it was farther from the conduit and it never had an issue again. Makes you wonder about the effect of working in such environments.

Re: Car allergic to vanilla ice cream (2000)

#469

Post by ajmurmann »

QuiDortDine wrote: post #394

Simpler but funny tech support anecdote: at some point, someone called me over and said their keyboard would print the letter 'e' repeatedly. I tried another keyboard of course, and it still did it! Rebooted the computer, still 'e's all over. Finally, I looked at her mouse: it was half of a wireless mouse-keyboard combo. Turns out, the keyboard hadn't been turned off before it went in the pile, and other keyboards on…

Bluetooth devices are the worst for this. I had a very similar case where the letter "z" would randomly be pressed. Same case of random Bluetooth keyboard in a pile. More obnoxious though was a Apple Mouse that kept trying to connect to one of our work stations. It over and over would pop up a dialog saying the mouse wants to connect. It would happen usually in the morning and last a few minutes during which you in essence couldn't work. There was no way in macOS to have it remember the decision to not connect. When we tried to just pair with it too get rid of the dialog it would fail. We never solved this one. It just stopped happening one day.

Re: Car allergic to vanilla ice cream (2000)

#470

Post by ajmurmann »

lotsofpulp wrote: post #125

I find it incredible that not only a family would eat ice cream every, but that they would travel to get it everyday instead of just having it on hand in the house.

Not to mention that the car company would send someone out not only to their home, but in the evening and not only once but for weeks. I'd even have a hard time believing this if they loved next door to the companies HQ. Either the world has changed a lot or this is totally made up.
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