Disclaimer: Some parts of this circuit carry dangerous Mains voltage. If you are a beginner, seek guidance from experienced users. Dealing with the 110 V/220 V AC mains voltage and measuring the AC load parameters are regarded as a challenge for ...
Some folks prefer pushbutton switches to take effect on push instead of release. These buttons do that very thing. I suppose it’s really just a matter of taste, but I’ve always liked momentary contact switches that act when you push ...
This basic beat oscillator makes continuous wave keyed code and single sideband suppressed carrier signals audible. A recent Design Idea from contributor Gavin Watkins shows an inexpensive add-on beat frequency oscillator (BFO) [ 1 ] for ...
Expensive shortwave radios include beat frequency oscillators, so why not also add one to an inexpensive radio version? Broadcast shortwave (SW) radio use may be declining, but there are still lots of interesting signals to listen to between 1.6 ...
This proposed design eliminates traditional additional requirements for AGC, AC coupling, and post amplification circuitry. This Design Idea presents a simple op-amp-based sine wave oscillator that directly generates a low-impedance bipolar output ...
A novel switch architecture caters to extended battery range coupled with robust protection and diagnostic strategies. For automotive control units, the smart output switches operating contactor coils, lamps, solenoids, PTC (positive temperature ...
This circuit enables you to generate remote control PWM test signals with a (very) generic (and cheap) chip. A recent Design Idea ( Ref. 1 ) illustrated the application of an interesting chip (the LTC6992 ) to remote control (RC) PWM test signal ...
Self-heated Darlingtion transistor pair linearly senses airflow using just two wires for both power in and signal out. Suppose we take a common TO-92 transistor and heat it to a constant temperature differential above ambient. The power input ...
Front-panel push button controls can conveniently adjust a PCB-mounted internal potentiometer’s resistance. Digital potentiometers in conjunction with MCUs find common use in analog circuits. The processor can adjust the gain of an amplifier, ...
Minimal circuit converts input frequency to a precision current source that also accommodates grounded inputs. I recently had the opportunity to share a design ( Ref. 1 ) for frequency to current loop conversion using the versatile (if somewhat ...