nº933

Precise refrigerator temperature alarm. When internal temperature exceeds preset value between 0 and 10 degrees Celsius a powerfull alarm signal is triggered. It can be heard even with door closed. Low current consumption in stand-by, Supply 4xNiMH

nº932

Simple "red led catch game" with adjustable speed, supply 2xNiMH

nº931

SW band to MW band frequency converter with 1 transistor, supply 4xNiMH.

nº930

Ganged variable capacitor with reading scale

nº929

Simple lamp flasher controlled by LDR, supply +5V_USB

nº928

Four levels clapper for incandescent lamp; low sensitivity to speech, high sensitivity to clapping, supply 230Vac/50Hz.

nº927

Dimmer for incandescent lamp with 4 levels: OFF, L_min, L_med, L_max; tact-switch operates with total galvanic isolation, supply 230Vac/50Hz.

nº926

Staircase lamp controlled by smartphone ringtone. The ringtone audio signal derived from earphones output activates staircase lamp for the predefined timing. Complete galvanic isolation between TRS plug and circuit hot side is achieved by: 1) using one optocoupler to trigger monostable circuit and 2) A photovoltaic led coupler consisting on the hot side white led voltage regulator coupled to yellow led which supplies energy to the optocoupler audio trigger amplifier.

nº925

Light controlled audio spectral glider, supply 3V

nº924

Audio effect "wah wah", suppy 3V

nº923

Longwave experimental radio receiver with 2 bipolar transistors and loudspeaker output. Operating by night, tuning at 252kHz, Radio Algérie, Chaîne 3, supply 3V