Cassette Interface Assistance

[allison]

On 2/28/17 12:56 PM, Chuck Guzis via cctalk wrote:
> 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
Only works for FM and frequency shift based formats.

Everyone had their own favorite.  I used to flip a bit doing biphase in 
software
at 2400 baud.  Minimal parts to none.

Allison
> 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
>