autopsy:

12►

This is my first Modem, this is a Acoustic coupler modem for Commodore PET but i could use it with a IEEE488 Interface for the Commodore 64.

The Commodore’s 8010 Modem is an IEEE-488 (1978 standard) device which communicates via any standard telephone.

The 8010 Modem meets Bell 103 standards for communication at a fixed rate of  00 BAUD. The telephone interface is acoustic so the modem is portable. This means Commodore computers can communicate with, large computer systems like The Source and MICRONET, and other small computers.

Initially Commodore supplied software will support the following applications, with many more to come.

1) Terminal emulation.
2) Disk file send and receive.
3) Wordpro 3 sequential file send.
4) Hardcopy using Commodore printers.
5) Disk spooling.

A switchable four-section bandpass filter provides out-of-band rejection assuring accurate processing of the input from received carrier, even at signal levels of less than -47 dBm.

Jitter-free data is guaranteed by a soft limiter and phase lock loop discriminator. The carrier detect circuitry prevents the CBM Modem from operating when excessive noise would produce errors or cause marginal operation. This feature also assures accurate teleprocessing connections and inhibits chatter when the received signal fades.