My latest "homebrew" project was a simple electronic for a squezze keyer combined with a large memory to store frequently used parts of a QSO. The memory consists of an EPROM (27C512) and contains 128 programable memories each of them up to 4096 points size. The information is organized into 16 banks. The banks are selected on the front panel via a hex switch (0...F). Each bank has 8 positions with different information. These positions are selected through a switch which is also on the front panel. Because you need only 1 bit for morse code, these 8 positions are actually the data outputs of the EPROM.
This is the front panel of the CWPROMMER. On the left side you can see the poti for the speed adjustment, followed by a switch to select the bit position and then a hexadecimal switch to select the bank. The switch on the right side has three position: up sends the selected memory, middle: off and down: operate the squezze paddle. The red led is a keying indicator.
The rear panel has a socket for the power supply, one for the squezze key and two outputs for positive and negative keying to be connected to the transceiver
I also wrote two little programs to create the binary data for the EPROM from a textfile. One program is a little editor to create a textfile with all information to be programmed into the 128 memory locations. The second program takes the generated textfile and converts it into binary information. This information can be programmed directly into the EPROM. I put these to programs together with a HPGL file of the schematic into a zipfile which you can download now. The schematic does not include the squezze electronic. The speed poti (100k) and both switches are also not shown.

November 1996

This document was created on the 07/11/96 using FlexED