We started out with an old modem and ended up with a useful circuit ... Next, following this schematic, wire up the resistors, capacitors, and diodes (click for larger size): Phone socket 1 ...

The modem itself is a boxy affair bearing all ... [Jared] built a block diagram of the circuit and determined the important frequencies for things like the local oscillator. He worked through ...

Generation One IFC Modem Circuit Card Specification: Pioneering Interoperability in Satcom Crafted by the Seamless Air Alliance Modem Expert Working Group, the Generation One IFC Modem Circuit ...