The sensor is S1 in this alarm that we found in a Radio Electronics magazine from May 1971. Several sensors can be used in series. The SCR supports equivalents from the 106 series.
This circuit was found in a 1967 Philips documentation. The circuit fires when light stops hitting the...
We found this circuit in a 1990 documentation. It draws one out of 10 numbers and during the draw...
This preamplifier for magnetic cartridges was found in the February 1990 issue of Radio...