gloog

To add to the other answers you’ve gotten, “cycles” and “hertz” are both still used. The frequency (in Hz) is a count of how many cycles are in a one second period. A datasheet for an electronic device might have the frequency it’s compatible with listed on it (typically 60Hz in the US, 50Hz in Europe).

For some signal processing and protection equipment you’d also see a number of cycles listed on the datasheet - that will always be paired with a “at X Hz” clarification, because it’s functionally telling you how long the device takes to operate. For utility line circuit breakers, for example, “3 cycle” and “5 cycle” breakers are the most common options in the US, where 3 cycles translates to “this breaker will be fully open within 3/60 of one second of a trip command.”

The context of the quoted section of the article is about what an acceptable false positive rate would be, not about what situations drunk driving would be acceptable.

Also a layperson, but while the courts may have ruled against certain details of background check requirements (like whether certain kinds of restraining orders can be used to disqualify someone from buying or possessing guns) they have not ruled against background checks being required for gun sales as a concept. The entire purpose of these kits, whether the manufacturer says so or not, is to bypass background check laws by selling something that technically doesn’t meet the definition of a firearm but can very easily be modified to become one.