Yet Another Modem 9k6
        (G3RUH Compatible)
        The modem is capable of 9600 bit/s operations and interfaces directly to the PC serial port from which it is also powered. It has a built-in HDLC controller which greatly simplifies the development of driver software and allows fast and reliable HDLC frame synchronization.
        The baseband codec features a GMSK - or cosine NLF - G3RUH compatible modulator, a powerful hardware digital carrier detector and a high resolution Rx clock recovery circuit.
        Updates

        YAM Release v1.10 (24 Nov 1997): yam1_10.zip
          • YAMSD110.PDF - Schematic Diagram (hardware release v1.10)
          • YAM110.MCS - FPGA Configuration File (hardware release v1.10)
          • README.TXT - Release Notes
        Modifications in v1.10 since previous release v1.7:
        Corrections:
          • In the schematic diagram the Pin 21 of the Xc5202 FPGA was
            erroneously left open. The error has been corrected and Pin 21
            has been tied to GND.
            • In the schematic diagram the power-supply pins of the TL064
            op-amp were erroneusly inverted. The error has been fixed
            and the power-supply pins tied to the right power rails.
          Updates:
          • For lovers of whistles and bells three LEDs have been added
            (PWR, ON-AIR and CD signals).
          • The Xc5202 pinout has been changed to improve the routability
            of a single layer PCB. Refer to the new schematic diagram for the
            details.
          • The PTT interface has been slightly simplified.
        Important Note: The new configuration file YAM110.MCS is NOT compatible with
        the hardware release v1.7 and should be used only in conjunction with the hardware release
        v1.10.
        Note that the batch files in the driver archives (TFX_COMx.BAT, YAMPKT.BAT) contains the command line:
          YAMINIT YAM17.MCS ...
        If you are to use the v1.10 YAM hardware correct this line to:
          YAMINIT YAM110.MCS ...

        PCB Layout v1.10
        Single-sided PCB for homebrewers (low-resolution drawings, not to scale):

          Top Overlay (~13 KB .gif file) - Untested.
          Bottom Layer (~19 KB .gif file) - Not mirrored. Untested.

        A double-sided PCB is under construction too and the first samples will be available very soon via our local ham association.
        Click here to download the drawings (~390KB, .pdf format).

        Drivers
        Nord><Link's "The Firmware eXtended" for YAM: tfxyam09.zip
          This software is subject to the ALAS license. Please read it before download.
          Any commercial use is prohibited.
          Archive contents:
          • YAMINIT.EXE - YAM modem configuration utility
          • YAM17.MCS - YAM modem configuration data (hardware release v.1.7)
          • TFX_YAM.COM - The Firmware for YAM
          • TFX_COMx.BAT - Sample TFX_YAM initialization batch files

        FlexNet YAM Driver v0.4 : yamser04.zip
        The FlexNet YAM driver has been developed by Jurgen Hasch, DG1SCR.
        An expecial thank to Juergen for his precious work.
        Archive contents:
          • YAMSER.EXE - The FlexNet driver
          • FL.BAT - Sample FlexNet initialization batch file
          • YAMSER.ENG - Documentation in English language.
          • YAMSER.DOC - Documentation in German language.

        YAM Packet Driver for NOS: yamnos.zip
        This is still an alfa release. Use it only for evaluation purposes since the P-persistence algorithm is not yet implemented.
          Archive contents:
          • YAMINIT.EXE - YAM modem configuration utility
          • YAM17.MCS - YAM modem configuration data (hardware release v.1.7)
          • YAM.COM - Packet Driver for the YAM modem
          • YAM.ASM - Packet Driver source code
          • YAMPKT.BAT - Sample YAM initialization batch file

        Documentation
        V1.7 Basic Documentation: yamdoc17.zip
          • YAMSD17.PDF - Schematic Diagram (hardware release v.1.7)
          • YAMPAR.TXT - Parts List
          • YAMPCB.PS - Luis Yanes' PCB - Solder side (not tested)
          • YAMSLK.PS - Luis Yanes' PCB - Silkscreen overlay (not tested)
          • EYE.GIF - YAM Eye Diagram

        V1.7 Core Documentation: yamcor17.zip
          • YAMCORE.PDF - YAM FPGA Core Schematics (hardware release v.1.7)
          • TXPROT.GIF - Serial interface transmission protocol
          • TXPROTD.GIF - Details of the serial interface transmission protocol

      Nico Palermo - IV3NWV. All rights reserved.
      If you have comments or suggestions on this device, email the designer at iv3nwv@microlet.com