USING the λ 2536.5 mercury resonance radiation as exciter and the medium quartz spectrograph with a fine slit, one of us 1 successfully recorded the doubling of the λ 2536.5 line in the spectrum of ...

Here is an ultra simple automatic light switch circuit for bedrooms. After construction, connect the input terminals of this circuit in parallel to the internal buzzer terminals of a Quartz-Alarm ...