Yes, am all aware that there are proper tools to do this "professionally". But this is way cooler. One and a half day suffice to erase them to 0xFF's.
Way faster than it used to be in the 70's? (debatable), but I otherwise DO miss the ozone layer.
NOTE from this site
"UV-C radiation, which is lethal, is emitted at wavelengths of 200-280 nm. Fortunately, UV-C is completely absorbed by atmospheric ozone and oxygen. Even with severe ozone reduction, UV-C radiation would still be absorbed by the remaining ozone."
EPROMs require UV-C's (according to wikipedia) ... hum .. anyway, 1.5 day to wipe my 27128's is an actual observation.
I have got 20 or so 271282's (salvaged from an arcade board), so this erasing delay is a non issue for my Console/Cartridge development.