#7468
Guenther
Spectator

Hi All,

a very nice and useful schematic indeed!

That remembers me to Experiment 89 and 90 of the old Egger/Braun Base manual:

  •  89: Soundlevel Meter (Schallpegelmesser)
  •  90: Burglar Alarm (Geräuschwarnanlage)

This two schematics were used / planned for the Lectron Bastelsätz sets (see there, including videos)

The problem of 90 is that the light only shows with a short flash any noise activity, but never leave ON until another noise will happen. So the light control is quite nice but not practicable because I would like to see the light for more than several seconds (= alarm !). Here the use of a Flip Flop will be the solution, like in your circuit.

Another planned Bastelsätz was the Remote Control Device (Fernsteuerung) – see there incl. video -, presumably a similar circuit which switch ON a light / TV set / radio and – with a second noise e.g. hand clapping – make it switched OFF. To switch a 230 VAC unit I have to use a relay with power contacts (not the Lectron relay). This is a dangerous area so it’s not recommended for assembling by non-experts!

The schematic:

Please note: the internal wiring of the Flipflop and the Impedance transformer are placed on a separate PCB and on the mainboard, see photo above. A control LED will show the active state.

As always: the combination of linear and digital functions (and – if meaningful – with relay) is a good possibility for understanding electronics!

Best,

Günther

  • This reply was modified 2 years, 7 months ago by Michael.
  • This reply was modified 2 years, 7 months ago by Michael.
  • This reply was modified 2 years, 7 months ago by Michael.
  • This reply was modified 2 years, 7 months ago by Michael. Reason: Changed font and size styling for easier reading. Also embedded hyperlink to Bastelsatz page