Wiring & diagram Info

Wednesday, October 15, 2014

Universal Active Filter Circuit Diagram

The circuit as shown gives the bandpass operation the transfer function calculated from FBP(s) = where = 1 + s/Qo>0 + s2/w02. The cut-off frequency, 0, and the Q-factor are given by 0 = g/C and Q = gR/2 where g is the trans-conductance at room temperature. Interchanging the capacitor C with the resistor R at the input of the circuit high-pass operation is obtained. A low-pass filter is obtained by applying two parallel connections ctf R and C as shown in Fig. 2. The low-pass operation may be much improved with the circuit as given in Fig. 3. Here the gain and Q may be set up separately with respect to the cut-off frequency according to the equations Q = 1/fB = 1 + R2/R!, A = Q2 and 0 = g ffi/C.

Universal Active Filter Circuit Diagram

Simple Optical Theremin Circuit Diagram

Normally, Theremin works by detecting hand proximity using capacitive coupling method. A Theremin circuit shown in the schematic diagram below use different method to control the pitch. The oscillator of this tone generator, both the volume and frequency are controlled using LDRs, a light sensitive electronic component, so we can call this circuit an optical Theremin. Look at the following schematic diagram.

Simple Optical Theremin Circuit Diagram

LDR1 control the frequency of this Theremin, while LDR2 control the volume level. We can place the LDR in two boxes where we can use our hand to control the aperture of the box, allowing smooth control of light amount that expose the LDR.

This light is expected to come from ambient light, entering the box through the hand controlled aperture. This optical Theremin assume a stable ambient light to produce smooth control. The output will be heard on a small loudspeaker, but will be in very low volume. You can just amplify this output with a standard audio power amplifier to get better loudness.

Simple Solar Flasher

This Simple Solar Flasher circuit is a single transistor fly back (Joule Thief) circuit that features a third coil. With it, flash duration and brightness is much enhanced, without resorting to large value capacitors.

Circuit Diagram:

Simple Discrete Sliding Tone Frequency Ramp Doorbell

This Discrete Sliding Tone (Frequency Ramp) Doorbell circuit produces a low tone that will slide up to higher frequency. The equivalent total resistance connected between the base of Q1 and ground (Rbg) , and coupling capacitor C1 determines the AF oscillator’s frequency. The resistance (Rbg) is equal to (R2+R1)R3.

Here is the schematic diagram of the circuit. The R2 is used to set the initial bias condition, adjusted to produce a pleasant low starting frequency doorbell tone. D1 will start to conduct when Capacitor C3 charge through R6 until it reaches D1 bias voltage level.

Then the value of Rbg is paralleled by R4 and D1, and R5-D2-D3, and the values of diode’s equivalent resistance is gradually decreased as the C3 voltage ramp up. This decreasing resistance value make the output tone slides up in frequency. Two different diode path is provided to extend the linear area of diode conduction transition slope. With two path with different biases, after the single diode path has saturated, the second path provide further linear increase at higher voltage level.

Discrete Sliding Tone (Frequency Ramp) Doorbell Circuit

Tuesday, October 14, 2014

3000W Power Inverter Circuit 12VDC to 230VAC

Parts list:

R1,R2,R31,R32 = 470k
R3,R10,R12,R18,R30,R36,R37,R38 = 100k
R4,R16 = Poti 50k
R5,R19 = 68k
R6 = 22 k
R7,R11,R13,R29 = 10k
R8,R22 = 2,2 k
R9,R15,R27,R28,R39 = 1M
R14 = 47k
R17 = 3,3M
R20 = 0,001 (see construction plan)
R21,R45 ... R64 = 100 Ohm
R23,R40,R41 = 1k
R24 = 150 Ohm

R33 = 0,1 Ohm / 17 Watt for 3000 Watt output max.
R34,R42 = 150 k
R35 = 470 Ohm
R43 = 4,7k / 0,5 Watt
R25,R26 = 10 Ohm
R44,R45,R46,R47 = 22 Ohm

C1 = 47nF (no ceramic capacitor - frequency stability!)
C2 = obsolete
C3,C25 = 4,7uF
C4,C9,C11,C24,C26 = 0,1uF
C5 = 10000 uF
C6,C7,C10,C14,C23 = 220uF
C8,C12,C20,C22 = 100uF/16Volt
C13 = 220uF/35 V (max. 25 Volt through charge pump)
C15,C16 = 47uF
C17,C18 = 10nF
C19,C21 = 1nF

D1,D2,D3,D5,D6,D9,D14,D15,D16,D18,D20 = 1N 4148
D4 = ZPD 12
D7 = ZPD 5,6
D17,D19 = ZPD 10
D8,D10,D11,D12,D13 = 1N 4001

IC1,IC9,IC10 = TL081
IC2 = CA3130E
IC12,IC13 = LM741
IC3,IC4,IC5,IC6 = 1 x 4093
IC7,IC8 = 1 x 4013
IC11 = 7812

T1,T4 = BCY59 or BC547 (T1 affects the pulse width regulator and thus voltage regulation!)
T2,T3,T11 = BCY79 or BC556
T5,T8,T10 = BS 250 (IRF9Z24N)
T6,T7,T9,T12 = 2 N 7000 (IRFZ24N)
T13... T28 = 16 x IRF 3205

LED1 red, overload protection
LED2 yellow, load detection

Tr1 = 3000 VA
Tr2 = small transformer 1 VA, 230V/6V

F1 = 250 A (100 Amperes for 1000 Watts output)
F2 = 75 degree celsius switch off

Relay1 = 12 V coil, 2 contacts

1 heat sink 200mm x 100 mm

PCB Layout:

Component Placement:

Technical Data:

Supply voltage: 12 Volt
Battery size: depending upon load, otherwise no restriction
Output voltage: 230 Volts rms (square wave voltage with duty cycle Tp=25% "modified sine")
Good for resistive, inductive and "pseudocapacitive" load (e.g. computers)
Efficiency: under full load approx. 95%
Quiescent current of control electronics: approx.. 0.05 A ... 0.1 A
Total: 0.5A to 2,5 A, depending upon quality and max. induction of the used transformer
Pulse width regulation for the stabilization of rms of the output voltage
Current limiter in case of short-circuit an thermal protection
Option: load detection

This 3000W inverter is suitable for:

Electric drills, fret saws, circular saws, electric chain saws, grinders
Vacuum cleaners, coffee machines, irons, dryers, mixers, sewing machines, electric razors, etc.
Lamps, energy-savings lamps
Electronic devices, e.g. music amplifiers, battery chargers
Computers and accessories, UPS
Televisions and radios
Ham radio transmitters, high voltage generators, among other things

Monday, October 13, 2014

Audio Detector Circuit

This electronic detector circuit is to do audio detection. The circuit is for detecting one of those 3.6khz (approx) beepers from Radio Shack. The component used is a single IC (LM324 quad op amp) and a handful of parts.

Notes:

The capacitor and resistor on the output of the peak detector are selected to give a reasonable decay time. I.e. so a single pulse doesnt stretch out and be miss-interpreted as an audio signal. I think I sample the output at 100ms intervals and signal a valid sound if three consecutive samples are true.
The only critical parts are the trimmer, capacitors and the 560 ohm resistor in the band pass filter. The diode is not critical: any small diode will do fine.
The trimmer is used to set the center frequency. I just run the beeper and adjust for the strongest output signal.
It uses a condenser mic, surplus. Probably any computer microphone will do. The 4.7K resistor is a typical load for those things.

Authorized by: Larry Barello, See more: Pressure Monitoring.

Infrared Light Photo Detector Circuit This is a basic infrared light photo detector circuit In this circuit the light falling on the phototransistor

Infrared Light Photo-Detector Circuit

This is a basic infrared light photo detector circuit. In this circuit the light falling on the phototransistor will be from an Infrared Light Emitting Diode (IrLED) but otherwise it is the same as the phototransistor circuit shown above.

When the light falling on the phototransistor (Q1) is blocked, its conductance will decrease and the voltage across Q1 will rise. When the voltage rises above 1/2 of the supply voltage the output of the comparator will turn ON and the LED will be lit.

Source: Infrared Light Photo-Detector