On 1/4/19 1:28 PM, André Fachat wrote: > > > Am 4. Januar 2019 13:17:08 schrieb Gerrit Heitsch > <gerrit@laosinh.s.bawue.de>: > >> On 1/4/19 12:22 PM, silverdr@wfmh.org.pl wrote: >>> >>> Do you remember how the analogue section was solved there? All >>> discrete or something like in 1541-II? >> >> The read amp seems to be an MC3470 in 18pin DIP. Not sure what they use >> for the write circuit, but there is a MC3346 next to the read amp which >> is a 'General purpose Transistor Array One Differentially connected Pair >> and three isolated Transistor Arrays'. Probably that plus some analogue >> tricks. >> >> Gerrit > > The MC3470 is BTW what Apple used in the Disk II anlogue board. So it > has been around for awhile Well, if it works and it cheap, why not use it? It's still easily available and still cheap (1 Euro) too. GerritReceived on 2019-01-04 14:01:30
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