A PIC Microprocessor Board
for Controlling EME Antennas

This page describes a project that was begun around 1998. In 2004, Jean-Jacques (F1EHN) began offering a printed board based on this design. I, KK6MK, am still the developer of the firmware for the board.

For the latest information, you should go to the F1EHN Site.

There you will find the latest EME System information, the latest PC software, and a printed board that is the current version of this design.

I should keep the latest firmware available on this page, but I recommend the F1EHN site as the best source for all the latest information, software, and hardware.

The F1EHN System

Several years ago, F1EHN, Jean-Jacques Maintoux, in France, designed a superb system for controlling antennas used to make Earth-Moon-Earth (EME) amateur radio contacts. This system is one of the most widely used by hams who make EME contacts. The heart of the system is an excellent PC program that runs on Microsoft Windows operating systems. The program tracks the position of the moon relative to the operating location. It can be used to steer an antenna and keep it pointed at the moon. The program also performs several other functions useful for EME contacts. A hardware interface board connects to one of the PC's serial COM ports and communicates with the program to complete the system. F1EHN makes this program available to the amateur community at no cost.

Origins of the New Controller Board

I worked with Jeffrey, WA6KBL, and Tay, W6HD, to design and test this board. The original goal was to make an interface between the F1EHN board and US Digital absolute encoders for positioning feedback. The design used a Microchip PIC microprocessor. After this was completed, I realized that it should be possible to put all of the functionality of the existing F1EHN controller board into a PIC-based design. This could have some advantages. Features that are now done on separate boards could be put on one board, fewer parts would be required, and newer parts that are more easily available could be used.

A new design was undertaken and the following goals were set:

This hardware and software has been completed and Tay, W6HD, has been using it without problems. Currently all the implementations that have been built are hand-wired prototypes. If there is enough interest from various people, we could do a layout and have PCBs built. Contact me if you are interested in this.

The Package

Two Microsoft Word documents were written in 2000 - 2004. As a historical reference, they are provided in this zip file: newbrddocs.zip

The details of the original [obsolete] design are contained in this zip file: ehnemu109.zip

This file contains:

The most recent version of firmware is in this file:
201g.zip *Updated 02/2004


Information on the US Digital A2 absolute encoders we used can be found at their site: http://www.usdigital.com

The free Microchip MPLAB IDE can be downloaded at: http://www.microchip.com


F1EHN Site