The PCS 103 Modem

The Backwater Message System was originally created to test the PCS103 modems. The PCS103 modem was designed by Michael Day for the Portland Computer Society to sell as a kit. Roger Giles created and provided a foam rubber case in which the modem components were mounted. The money received for the modem kits was used to buy and operate the PCS BBS system.

Later on, the company that Michael Day was working for at the time, Edge Technology, decided that they wanted to sell the modem. RCA had sent a tender asking for a price on modems to use with their teletype machines.

An agreement was made between Edge Tech and PCS. Edge Technology got the rights to sell the modem as a complete device. PCS got the rights to sell the modem as a kit. Edge Technology sold over 500 of the modems to various customers. PCS sold over 200 kits in the Portland area.

The files provided here are copies of the manual for the PCS 103 Modem kit. The files are copied from the revision 3 manual, which was the last manual made for the modem.

We hope you enjoy this bit of history.


You can download the entire set of PCS103 files here:


You can look at or download individual PCS103 manual files here:


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