i’ve seen this a LOT.  products are UL or CE approved, then when they actually go to market, parts are left out to save money.  This 12vdc power supply is a perfect example, they left out the upstream line filter, a choke, and two capacitors.  i’m going to start a new category for these things when i find them.

you can see here the AC power cord, the fuse, and a single filter capacitor (red).  MIssing is the bifilar choke, and two large capacitors.  these are usually expensive (compared to other components) and often have to be hand installed.  leaving these out likely reduced the cost of parts 5 to 10%.

also missing are two capacitors likely to filter the main chopper transistor to the right.

what does this mean? it means this power supply when running under load made all sorts of very strong radio signals that can interfere with other nearby electronics.  these missing components kept the unit “clean”, which is what the UL and CE inspections look for.  this unit for sure was in violation of FCC part 15, messed up all my satellite reception (UHF) and birdied all over the HF.  it was sold with a nice 12v peltier refrigerator so was expected to be used in the garage or in the field i suppose?

they passed these inspections, then took out the parts that made them pass.

very much like the factory taking out the catalytic converter in your car after passing smog.

or VW jacking the computer in diesels?