Circuits & Schematics - Measurement

Famous analog designer and author Jim Williams published an awesome design in 1986 for a 100-MHz voltage to frequency converter ( Ref. 1 ). He named this high-climber (picture it on the roof of the Empire State building swatting biplanes out of the ...

RTDs (resistance-temperature detectors) are the preferred sensor choices for designs requiring precision. Although RTDs are approximately linear over the limited temperature range of 0 to 100 C, these sensors exhibit a slight but progressively more ...

The original application of the circuit in Figure 1 was to locate coins, but it applies wherever you need to locate metal objects. The circuit uses a beat-frequency technique: Whenever a metal object comes close to the search coil, the metal causes ...

Figure 1’s silly-simple voltage-to-time ADC is an exercise in dynamic range. Assuming that it is used with a 10-MHz counter/timer, its resolution is roughly 10 µV per count for inputs around 0 V and 100 mV per count at 1 kV, and it ...

Figure 1 is a cheap and cheerful voltage inverter I offered awhile back in “A simple, accurate, and efficient charge pump voltage inverter for $1” ( Ref. 1 ). Figure 1. The generic and versatile xx4053 provides the basis for a cheap, ...

ADC circuits that resolve signal into 20 or more bits need a low-noise signal source for measuring parameters such as harmonic distortion or effective number of bits. A notch filter removes the fundamental frequency from the oscillators signal for ...

Mystery solved? Not quite. I made a test coupon of the output transmission line and measured it. Over the crossover region, it showed a mere 0.04 dB loss with increasing frequency, much less than the measured result. I turned my attention back to ...

Students, hobbyists, and professionals today enjoy unprecedented access to powerful and affordable test equipment for understanding and building electronic projects. But as enthusiast projects have become more advanced and ambitious, it is still ...

This circuit is a simple sweep generator. The sawtooth is generated by the PNP transistor and the 555 . The transistor together with the 2 diodes at the base form a constant current source which charges the 330 nF capacitor. If 2/3V CC (=6 V) is ...