The hardware (1995 design).

This is the decoder/generator hardware for HRPT, CHRPT and HRI (note: no HRI after december 2005!)

between EPROM and RAM module: Dip switch. Just 2 switches are used, to select between HRPT, CHRPT and PDUS. (Selection between decoders and generators is done via the parallel port.) This dip-switch is replaced by connectors/jumpers on the new PCB.

At the left the trimmer to adjust the VCO frequency.

Where to get FPGAs

Here are a few addresses where you can try to get the FPGA's. If you know other addresses please let me know, so I can add them to the list.
Note that this is just a collection of possible addresses; I don't check this info from time to time if it is still valid. So, no guaranty!

Make sure that you get the right type in the right package:

  • XC3042-70PC84
  • XC3042A-7PC84

    Note: Xilinx type XC3042L is a 3.5V type, so you need different EPROM/RAM/74HC14 and parallel port types (3.5V equivalents) or 3.5<-->5V translators. The schematic and EPROM content stay the same.

    NOTE: For future designs maybe just the XC3042A type will be possible to use. So, if you have the choice between XC3042 and XC3042A then use XC3042A.

    Digi-Keyhttp://www.digi-key.comXC3042A-7PC84C, XC3042-100PC84C
    Avnet Try
    and enter near Enter your Part number(s): xc3042
    Display ElectronicaUtrecht, the Netherlandsnot in stock

    How to get a PCB

    PCB info if you want to make your own PCB.
    See Eprom files if you want to program your own EPROM.

    PCB and EPROM can be ordered at: farcircuits.
    In this link, go to the table below, and choose:
    DTMF Encoders, Decoders & Controllers
    Last item in this page is the HRPT decoder.

    Incl. shipping
    PCB Eur. 13,00
    EPROM Eur. 10,00
    PCB + EPROMEur. 23,-

    Order form in html: order.htm
    Same, in pdf format: order pdf

    Please mention on the form that you want to order the HRPT/PDUS DECODER BOARD and/or EPROM for HRPT/PDUS decoder.