Couldn't a cheap diode fix that polarity reversal problem?
If you know how to insert one. I would assume it would have been pre-installed.
Not having this type of protection is what males emachines cheeper.
My electronics teacher in high school brought us a project — fix his 6-meter marine radio.
The cleaning people had disconnected his battery, and reconnected it backwards. He hadn’t noticed, turned on the radio, and when it didn’t work proceeded to push button after button.
Multiple circuits were fried, which made it a challenging task for us, since we had to work our way through a series of failures.
The first circuit to fry? The diode that was placed across the inputs which was supposed to short the power if it was hooked backwards, blowing the fuse.
I haven't fooled around with this stuff in a long time, but I think one diode could prevent the damage - and four diodes (aka a bridge rectifier) could allow it to continue operating normally?