Should see some of the stunts pulled by USB chargers and car power adapters. Horrendously dangerous devices - no filtering, no regulating, no fuses. It's not just people being stupid and buying cheap adapters, though that doesn't help, it's companies supplying high value devices with these dangerous adapters.
With the above, you've been duped by a fake antenna, that's not so bad. At least it wasn't a power charger that overloads the battery and starts a chemical fire and burns down your car/house.
Yes, I have a big gripe with power adapters/converters...