Open Computing History Project

This month's featured interview revisits the early days of dial-up bulletin board systems through the recollections of a sysop who ran a two-line BBS out of a spare bedroom in Ohio from 1986 to 1991. The system, built around an IBM PC XT clone and a pair of 1200-baud modems, hosted a small but devoted local community of callers trading files, playing door games, and arguing about hardware on public message boards.

Volunteers at the project's hardware lab have finished a six-month restoration of a PDP-11/70 front panel donated by a retired systems engineer. The switch register and all of the indicator lamps now work, and the panel is on display in the lab.

We have added a scanned rate card from a regional timesharing bureau, listing connect-time, CPU and storage charges for 1979. The card was found tucked inside a programming manual donated earlier this year.

Rate cards like this one are a small but useful source for anyone researching what computing actually cost before personal computers. This one lists separate prime-time and evening rates for connect time, charges per CPU second, monthly rates for disk storage by the track, and a surcharge for printing at the bureau's own site.

We are looking for volunteers to help catalogue a recent donation of core memory planes and associated documentation. The donation came from a retired field engineer and includes planes from several different mainframe and minicomputer systems, some still in their original shipping cartons.

The work involves photographing each plane, recording its markings and dimensions, and matching it against the documentation where we can. No prior hardware experience is needed, only patience and a steady hand. Training will be given at the start of the next lab session.

A visiting research assistant spent the summer running period benchmark programs across six home computers from the project's collection. The aim was to see how well the published magazine benchmarks of the time hold up when repeated on real hardware that is now more than 25 years old.

Our hardware group has written up the repair notes we have collected over the past year for membrane keyboards found in early 1980s home computers. Membrane keyboards were cheap to make and are now the most common point of failure in the machines we receive.

The notes cover the usual problems: cracked traces on the ribbon tail, keys that stop registering after the conductive ink wears off, and connectors that have corroded from years in a damp basement. For each machine we list what has worked for us, what has not, and which repairs we consider reversible.

The archive has received a nearly complete run of a regional home computing hobbyist magazine published between 1981 and 1986. The donor subscribed from the second issue onward and kept every copy in good condition, with only three issues missing from the five-year run.

We have finished transcribing a set of ARPANET host tables covering the decade from 1973 to the NCP-to-TCP/IP transition in January 1983. The tables were printed out at regular intervals by a site that kept them for reference, and they were donated to the project last spring along with a box of RFC printouts.