On 02/28/2017 09:42 AM, Seth Morabito via cctalk wrote:
Synertek used an LM311 (an LM358 would work just fine)
to build a
comparator circuit. I _think_ you could use this exact circuit to
take the analog output from the CoCo and turn it into a 5V sqauare
wave.
I don't know a thing about the CoCo cassette format. I know that back
in the day when things like the KC standard were the rage, a NE567 PLL
was considered the cat's whiskers for data recovery. But again, I don't
know what the CoCo cassette standard looks like.
Also, you may want to look at the IBM 5150 (PC) cassette circuit. My
recollection was that it was pretty robust, even if few made use of the
facility.
--Chuck