Automatic 9V Battery Charger

This is the scheme diagram of automatic 9V battery charger circuit, the parts list provided below the schematic image. The circuit was designed by Jan Hamer, translated by Tony Van Roon dan republished in this circuit diagram site. The circuit details are based on european standards: 120E, 150E, etc. The ‘E’ just stands for Ohms… Read More »

Motion Filter Effect

This motion filter effect circuit will controls the initial frequency and controls how much the envelope follower responds to the input signal. An envelope follower/filter combination translates the typical dynamic properties of your axe into modulated timbral changes too, you could feel of it as an automatic wah-wah pedal. Independent Initial Frequency and Sensitivity knobs… Read More »

6V Gel Cell Battery Charger

The following scheme diagram is the battery charger circuit for 6V Gel Cell battery type only. Components List: R1 = 22 ohm, 1W R2 = 270 ohm R3 = 220 ohm *R4 = 715 ohm, 1% *R5 = 3.57K, 1% *R6 = 1.40K, 1% *R7 = 1.47K, 1% C1 = 0.1uF, ceramic C2 = 0.1uF,… Read More »

Theremin Music Instrument

The following diagram is the Theremin music instrument effect. A guitar or instrument amplifier is an ideal companion unit for the theremin; either one allows bass or treble boost, as desired, and fuzz (distortion) or reverberation (if these features are incorporated in the amplifier”s circuit). Simply provide a suitable cable plug and connect the theremin”s… Read More »

Six LED Stereo VU Display

The following image is the scheme diagram of six LED stereo VU display circuit which build using Dot/Bar Display Driver IC LM3915. This VU display should be connected before amplifier module circuit. You may connect this circuit at pre-amp output, tone control input/output or equaliser input/output. This circuit powered with 12V DC supply. About LM3915:… Read More »