Comment by lnsru

The thing is that one needs understanding of an electrical engineer to debug circuits one wants to repair. When you have understanding you can do some voltage measurements and try to identify faulty part. There is gazillion different parts now, that wasn’t the case 2 decades ago.

I know few people who repaired their washing machines just watching youtube videos. No skills and no knowledge. That’s the best error you can find - series error. All the appliances of the same manufacturer built in the 5 years will predictably fail and replacing 20 cent regulator revives the machine.

There are then random faults, that need deep knowledge and hours of debugging. They’re not economically viable to repair unless the machinery is very expensive. Good example is 400€ transistor replacement in €20k Tektronix probe.

Then there are things one shouldn’t touch - Tesla battery packs and open microwave ovens for example. Enough energy to kill or badly injure the unlucky hobbyists (in German): https://www.kosmo.at/tesla-akku-explodiert-mann-schwer-verle...

There are enough analog electronics to repair what requires deep analog design knowledge. Music instruments and radio equipment might fall into this category.

I would say, the repairs make no sense in the future that comes. With more and more electronics and programmable components the repairs are not economically viable. I am designing a motherboard with MPM54304 PMIC and a microprocessor. Both are programmed and without firmware sources and circuit diagram one will not able to recreate desired functionality. After product release I will organize workshop for my colleagues from service department and they will still come to me to discuss the repairs when some early faulty products will be send back by customers.