We recently got rid of a four year old microwave where the magnetron turned on spontaneously and silently when the door was closed, runaway heating the box. Control panel, lights, turntable, fan, everything is idle.<p>Manufacturer didn't consider this an interesting defect and refused to swap out-of-warranty. The lack of give-a-shit in appliances is becoming apparent.
I migrated our house to a "commercial" variant of the microwave oven [1] as I was tired of all the over-engineering and annoying patterns in modern microwaves.<p>This microwave has exactly UI element other than the door - a digital dial that goes from 10s-6m. No start/cancel, no power level, no defrost, no program mode. I don't "cook" using the oven, only reheat or very rarely heat/boil small quantities of water.<p>The microwave beeps only once after complete and it's not incredibly loud.<p>Despite my kids literally abusing this device, it's been rock solid for 7+ years. Amusingly my company started putting these same exact models in our office break/kitchen areas a couple years after I bought mine.<p>[1] <a href="https://www.amazon.com/gp/product/B00BDF5ZNS" rel="nofollow">https://www.amazon.com/gp/product/B00BDF5ZNS</a>
There exists only one correct design of microwave ovens.
It has zero ICs.
It has exactly two direct user-inputs and one indirect.<p>The two dials select on-time and duty-cycle (cooking time and "power").
The third input is the safety switch which deactivates the cycle when the door opens.<p>This design is the most userfriendly, the most economic and the most reliable.<p>This is the hill I will die on.
Notice that door switch middle is a crowbar[1] which is there to prevent the magnetron from powering on when all else fails (and there is a lot of interlocking). My friends parents had a microwave that kept dying so I opened it up and realized one of the three switches was a crowbar and it blew the fuse. I changed the fuse and it powered on again and ran for a few more days until it blew again. They decided it was unsafe and canned it.<p>1. <a href="https://en.wikipedia.org/wiki/Crowbar_(circuit)" rel="nofollow">https://en.wikipedia.org/wiki/Crowbar_(circuit)</a>
Fascinating in that our GE microwave (still actively sold) has an undisclosed feature that if you lift the door, when fully closed, by no more than a few mm, the microwave will start. I noticed this when cleaning the enclosure with a rag and my hand ever so slightly lifted up the door from the bottom. I can see how a consumer could wedge a kitchen utensil or plate accidentally under the microwave causing it to start and continue to run. Zero logic protection.
The title is a bit clickbaity, since the actual "oven" part (the magnetron) stayed off. As it should, since the safeties for it are much more robust than the other parts:<p><i>I’m quite impressed by how many independent mechanisms there are to prevent the magnetron from accidentally turning on. Not only are there three door switches to ensure the door is closed, there’s also a mechanism to guard against a faulty microcontroller or software.</i><p>Personally, I think the ones with mechnical controls, no microcontroller, are the most reliable and also easiest to repair.
One of the comments linked to an article about keyboard problems caused by a LED, which was previously discussed here:<p><a href="https://news.ycombinator.com/item?id=36581204">https://news.ycombinator.com/item?id=36581204</a> - Repair adventure: A single white LED causing stuck keys on a RN988 keyboard (2023-07-05)<p>I wasn't thinking about the color of the LED at the time, but after reading this article, I wonder if we should prefer products with green LEDs in general, like green LEDs are just more reliable than blue/white LEDs for some reason?<p>Also, I can't seem to find microwave ovens with red LEDs.
Nice investigation!<p>My 25 year old microwave is really solid, except for the lamp, which has blown. It's an old bulb so it should be replaceable - except that physically there's no way to do it without unscrewing the magnetron, which is well into scary territory - you need to basically re-qualify it after reassembly by scanning for leaks with a professional instrument. I don't want to throw it away because it still works, but fixing the lamp would cost more than buying a new one.
I have a Samsung microwave with a really weird bug. If the door is just a few millimetres ajar, it turns on by itself. It's not just mine either, a lot of reviewers point out the same. It seems to be a design flaw. It's not a huge issue, since I'm not exactly in the habit of positioning the door in a half-open state.<p>My guess is that they have some broken/inverted logic related to the "turn off if the door is open" feature.
Interesting that he thinks the clock would be better with a 32kHz crystal than with monitoring the 60Hz power frequency. The power line frequency is very tightly regulated over the long term, and should have an overall better accuracy.
My microwave is a 1993 Panasonic. It sat in a basement for about 10 of the intervening years, but has been a daily driver for the last 6-7. Comparing it to current retail units, it's remarkable how little has changed in that time.
Once had to repair my washing machine. It was easy to identify the problem after removing the control board: a single $1 chip integrating nothing more than 4 motor driver FETs cooked itself due to the lack of a heatsink. Unfortunately could not fix it because the board had a thick layer of some glue-like stuff which I could not remove, and so had to replace the whole board, doubling its lifetime to more than 10 years. It still rocks but got out of balance and is quite noisy sometimes.
> "I’m quite impressed by how many independent mechanisms there are to prevent the magnetron from accidentally turning on. "<p>Ok, I've never been really fond of microwave ovens so I don't use mine that much. After reading this I am starting to fear my microwave, definitely.
I scared myself with my microwave, a cheaper Samsung. Somehow it turned “itself” on when I opened the door once. I quickly slammed it shot and jumped back. Hopefully it’s this exact failure and the magnetron didn’t actually start.
Partially off-topic, but I’ve seen complaints in the thread about microwaves in general. Here’s the trick — buy a commercial microwave. They’re reliable, powerful, and have only a few features. They come in all sizes.<p>You’ll put less duty on one in a month than a commercial kitchen does in one day, so it will last forever. Time is money in a kitchen so they’re powerful and fast. They tend to have very simple, direct controls, rather than a myriad of popcorn/pizza/whatever buttons. Commercial microwaves often have an integrated diffuser, so they don’t need the stupid rotating glass plate in the bottom.