This circuit was designed to obtain a valve-like distorted sound from an electric guitar or other musical instrument. For this purpose a very high gain, three-FET amplifier circuit, was used. The output square wave shows marked rounded corners, typical of valve-circuits when driven into saturation. Therefore, the distorted sound obtained from such a device has a peculiar tone, much loved by most leading guitarists.

Circuit set-up using oscilloscope and sine wave generator: Connect a 1KHz sine wave generator to J1 and the oscilloscope to J2. Adjust R4 until the output square wave shows equal mark-space ratio. "By ear" circuit set-up: Connect a musical instrument to J1 and an amplifier to J2. Carefully adjust R4 in order to obtain as maximum output sound intensity as possible.

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]