This is an adapter attached to a TV set. This machine changes a TV to a Oscilloscope. See the photo! This photo indicates a sine wave 50mV 120Hz. See the circuit! Free oscillater makes an 15kHz pulse signal (A). This signal is amplified by an buffer AMP. On the other hand , an amplifier makes 300 times of input signal. And it is shifted to 6V center. A comparater compares a voltage (C) and (B). this comparater makes an pulse width modulated signal on (D) point. Differencial circuit makes a small pulse on the changing timing of the pulse. Buffer receives two signals ,(A) and (E). Therefore it is called as an adder. This machine is able to indicates only 60Hz or 120Hz or 180Hz

Build your own LC Meter and start making your own coils and inductors. This LC Meter allows to measure incredibly small inductances making it perfect tool for making all types of RF coils. LC Meter can measure inductances starting from 10nH - 1000nH, 1uH - 1000uH, 1mH - 100mH and capacitances from 0.1pF up to 900nF. The circuit includes an auto ranging and "Zero Out" function to make sure the readings are as accurate as possible ... [more]