A Pseudo Cursor for Oscilloscopes: Add a Calibrated Time Base to Dual-Trace Scopes

The electronics hobbyist can add this project to an uncalibrated oscilloscope to make it much more accurate. The increase from about three per cent accuracy to 1000 times that is the aim of this circuit, which is also available in kit form for about thirty-five dollars. It is based on an oscillating crystal and decade divide-by chips. The theory behind the device, plus information to adapt the plan to differing scopes, is given. Construction is simple enough as to receive only one paragraph of comment.