The new low-cost 9k6 FSK modem for centronics interface

PICPAR - Printer Port FSK Modem

This brand new development, carried out together with Henning, DF9IC, integrates all digital functions of the conventional PAR96 modem into a PIC microprocessor. It is directly connected to the PC's printer port and allows unlimited 9600Bd FSK operations. A 19200Bd version is available too.
The result is a 9k6 FSK modem with only three chips. Because it consumes only 4 mA power, it can be supplied directly from the centronics interface. The PICPAR is 100% compatible to the PAR96, so all existing drivers can be used. The only difference is the missing of the external power supply, also the PAR96 only provides one filter FIR characteristic instead of eight as with the PAR96. But this difference should not matter with modern equiment with linear transmission characteristics.
Because we use powerful rail-to-rail-OpAmps in the analog section of the modem, a high output deviation of up to 3.5Vss is achieved.
The modem is delivered either as a kit or as assembled unit in a small plastic housing (size 91 * 67 * 25 mm). A still smaller SMD version is planned for the near future. Please note, that a radio modified for 9600Bd is also required for this modem.
There is a driver for this modem in BayCom version 1.60, a TFXPAR driver is available to run hostmode programs on that modem and there is also a driver for it in the most recent LINUX kernel.