Today, my radio went up in smoke

So the local newspaper reminded of a few things to have at home to sustain 72h and thought perhaps should look into a "new" radio, a grandma style that can take EMI if and when the artificial sun lights up above us, or is it even possible to make a semiconductor device surviving, the antenna is a dilemma.
 
Ok, the problem (seems to) have been fixed, all is back to normal.
But there’s damage, all plugged chargers etc. are gone. Amazingly, our 12V halogen-lamps (on a transformer) survived without any sign of damage.
This makes me think of the trend to build amps with smps‘s (ACA, Sony VFET…)—would they be toast just as the radio?
 
Jolly good! What further measures were taken to solve the problem?

I think there are smps and smps! Expensive amps presumably utilise the most advanced, robust and reliable smps design.
I sometimes encountered burning wall warts - but no damage on the secondary side equipment. This may be plausible, simply because the tiny transformer transfers only a fraction of the primary single surge that is soaked by the bulk caps.
 
Jolly good! What further measures were taken to solve the problem?
So, the good ol‘ transformers aren’t „the last hope“…

Actually, I don‘t know what measured have been taken. Electrician came a second time and made some repairs.replacements. I‘d say he was a little more thorough than the first time. Now, everybody in the house is hoping nothing sas overlooked. 🫣
 
When the first MiG-25 was flown to Japan by a defecting pilot, it was taken apart and analyzed.
The Americans fell over laughing at the valve based electronics, until someone pointed out that it would still work when a nuclear event occurred, something that was entirely possible in a war.
Semis would not survive.

The thing had a 600kW radar output, known to kill rabbits on the runway if on full power, instructions were to use full power only after take off.

Please put a suitably rated MOV / voltage protection device at the mains inlet to protect your entire house equipment from such events in the future.
Wires do corrode, screws do come loose.
 
Ok, the problem (seems to) have been fixed, all is back to normal.
But there’s damage, all plugged chargers etc. are gone. Amazingly, our 12V halogen-lamps (on a transformer) survived without any sign of damage.
This makes me think of the trend to build amps with smps‘s (ACA, Sony VFET…)—would they be toast just as the radio?
Simple devices often can take serious abuse (for a short time). It will shorten their lifespan though. Complex modern (Far East produced) electronics often go immediately when the fault occurs. No matter what guru recommend SMPS, one better not uses them in audio as they have no real advantages in low power devices except their low price. They take away the mains voltage/PSU issue as it seems mains voltage is horror to some and the word liability gives shivers to companies that sell kits. Given the fact that DIY slowly is dying new DIYers apparently can be persuaded to build very simple low part count stuff with ready made adapters/wall warts. This is a commercial choice, nothing else. The fact that those SMPS need an extra filter tells something. The campaign however works OK as now one needs to defend using linear PSU's 😀

Built in PSU's that are switched on and off with real mains switches are reliable and stuff truely is switched off. Win-win. Chances of incidents goes down by factors compared to "green" wall warts that are powered on 24/7.
 
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Injection wins hands down on most aspects and some of them are forced so no choice really 🙂

Anyway it is up to the builder to use SMPS for below 50VA application in DIY audio but it is not a choice for quality/longevity. It is just "cheap & easy" camouflaged with blah blah.
 
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Injection wins hands down on most aspects and some of them are forced so no choice really 🙂

Anyway it is up to the builder to use SMPS for below 50VA application in DIY audio but it is not a choice for quality/longevity. It is just "cheap & easy" camouflaged with blah blah.
I ran into one of the better known and popular contributors here who when discussing power supply filter capacitors was arguing with “ C dv/dt = i “

Of course that assumes V dc/dt is not an issue.

Then there was the fellow who did not understand why a diode would fail at 35% of the PIV rating in a DC power supply.

As many of the finished product power supplies are switchers, I believe it is a general lack of basic knowledge that has folks using them.

Seems time to post a DIY article on designing a power supply. I did in the past promise to do a magazine article on selecting small fuses. (Still collecting data on how real fuses open. Not very surprising some of the cheap fuses are not consistent.)