Diagram Guide

Saturday, August 23, 2014

AB Transistor Audio Power Amplifier Wiring diagram Schematic

This is a class AB transistor power amplifier. It is a simple amplifier to build, uses standard parts and is stable and reliable. The entire schema utilizes commonly available components and may be simply built over a general-purpose board. But this amplifier has very good sound quality.

AB Transistor Audio Power Amplifier Circuit Diagram

There are eleven transistors, including four in the output stage. Q1 and Q2 transistor must be between 3 and 5 amperes power transistors. Q4 and Q5 must be between 100mA and 500mA driver transistors. Other transistors are 10mA small driver transistors. Q1, Q4 and Q2, Q5 are complementary pairs, they make complementary darlington pairs.

PART LIST
R1	1.5KΩ ¼W
R2	150Ω ¼W
R3	1KΩ ¼W
R4	0.22Ω 2W
R5	0.22Ω 2W
R6	39KΩ ¼W
R7	1KΩ ¼W
R8	120Ω ¼W
R9	6.8KΩ ¼W
R10	6.8KΩ ¼W
R11	47KΩ ¼W
R12	47KΩ ¼W
R13	2.2KΩ ¼W
R14	180KΩ ¼W
R15	18KΩ ¼W
C1	22pF Ceramic
C2	4.7µF 16V
C3	1000µF 25V
C4	100µF 25V
D1	1N4148
D2	1N4148
Q1	2SD313
Q2	2SB507
Q3	2SA733
Q4	2SB560
Q5	2SD400
Q6, Q7, Q8, Q9, Q10	2SA733
Q11	2SD400
LS1	4Ω 20W SPEAKER

Power output of the amplifier

Supply voltage (Vs)	= 20V
Speaker impedance (R)	= 4Ω
Peak to peak voltage (Vpp)	= 20-2 =18V
Peak voltage	= 9V
Maximum output (Pmax)	= 9V²/2R
	= 81/8
	= 10W

10W is much enough for the day today home usage.
Amplification of this amplifier (A)

A	= R6/R13+1
	= 39KΩ/2.2KΩ+1
	= 18

Volume control can be added to the schema by connecting a 10KΩ POT in series to the input of the amplifier.

Q1 and Q2 must be kept sufficiently cool, so it is mounted on a suitable heat sink. If you used single heat sink please use insulation between transistors and heat sink.

3 3 5 Watt FM transmitter circuit

This is 3-3.5 Watt FM transmitter schema. With this power, it should be able to reach 3-5 KM distance. The frequency range is about 90-110 MHz.

Component list

Part	Total Qty.	Description
R1,R4,R14,R15	4	10K 1/4W Resistor
R2,R3	2	22K 1/4W Resistor
R5,R13	2	3.9K 1/4W Resistor
R6,R11	2	680 Ohm 1/4W Resistor
R7	1	150 Ohm 1/4W Resistor
R8,R12	2	100 Ohm 1/4W Resistor
R9	1	68 Ohm 1/4W Resistor
R10	1	6.8K 1/4W Resistor
C1	1	4.7pF Ceramic Disc Capacitor
C2,C3,C4,C5,C7,C11,C12	7	100nF Ceramic Disc Capacitor
C6,C9,C10	3	10nF Ceramic Disc Capacitor
C8,C14	2	60pF Trimmer Capacitor
C13	1	82pF Ceramic Disc Capacitor
C15	1	27pF Ceramic Disc Capacitor
C16	1	22pF Ceramic Disc Capacitor
C17	1	10uF 25V Electrolytic Capacitor
C18	1	33pF Ceramic Disc Capacitor
C19	1	18pF Ceramic Disc Capacitor
C20	1	12pF Ceramic Disc Capacitor
C21,C22,C23,C24	4	40pF Trimmer Capacitor
C25	1	5pF Ceramic Disc Capacitor
L1	1	5 WDG, Dia 6 mm, 1 mm CuAg, Space 1 mm
L2,L3,L5,L7,L9	5	6-hole Ferroxcube Wide band HF Choke (5 WDG)
L4,L6,L8	3	1.5 WDG, Dia 6 mm, 1 mm CuAg, Space 1 mm
L10	1	8 WDG, Dia 5 mm, 1 mm CuAg, Space 1 mm
D1	1	BB405, BB102 or equal (most varicaps with C = 2-20 pF [approx.])
Q1	1	2N3866
Q2,Q4	2	2N2219A
Q3	1	BF115
Q5	1	2N3553
U1	1	7810 Regulator
MIC	1	Electret Microphone
MISC	1	PC Board, Wire For Antenna, Heatsinks

Source: electronic-lab.com

Room Noise Detector

This schema is intended to signal, through a flashing LED, the exceeding of a fixed threshold in room noise, chosen from three fixed levels, namely 50, 70 & 85 dB. Two Op-amps provide the necessary schema gain for sounds picked-up by a miniature electret microphone to drive a LED. With SW1 in the first position the schema is off. Second, third and fourth positions power the schema and set the input sensitivity threshold to 85, 70 & 50 dB respectively.Current drawing is <1ma>

Noise

Parts:
R1____________10K 1/4W Resistor
R2,R3_________22K 1/4W Resistors
R4___________100K 1/4W Resistor
R5,R9,R10_____56K 1/4W Resistors
R6_____________5K6 1/4W Resistor
R7___________560R 1/4W Resistor
R8_____________2K2 1/4W Resistor
R11____________1K 1/4W Resistor
R12___________33K 1/4W Resistor
R13__________330R 1/4W Resistor
C1___________100nF 63V Polyester Capacitor
C2____________10µF 25V Electrolytic Capacitor
C3___________470µF 25V Electrolytic Capacitor
C4____________47µF 25V Electrolytic Capacitor
D1_____________5mm. Red LED
IC1__________LM358 Low Power Dual Op-amp
Q1___________BC327 45V 800mA PNP Transistor
MIC1_________Miniature electret microphone
SW1__________2 poles 4 ways rotary switch
B1___________9V PP3 Battery Clip for PP3 Battery

Use:

* Place the small box containing the schema in the room where you intend to measure ambient noise. * The 50 dB setting is provided to monitor the noise in the bedroom at night. If the LED is steady on, or flashes bright often, then your bedroom is inadequate and too noisy for sleep. * The 70 dB setting is for living-rooms. If this level is often exceeded during the day, your apartment is rather uncomfortable. * If noise level is constantly over 85 dB, 8 hours a day, then you are living in a dangerous environment.

dB Example of sound sources

20 Quiet garden, electric-clock ticking, drizzling rain 30 Blast of wind, whisper @ 1 m. 40 Countryside areas, quiet apartment, wrinkling paper @ 1 m. 50 Residential areas, quiet streets, fridges, conversation @ 1 m. 55 Offices, air-conditioners 60 Alarm-clocks, radio & TV sets at normal volume 64 Washing machines, quiet typewriters 67 Hair-dryers, crowded restaurants 69 Dish-washers, floor-polishers 70 Loud conversation, noisy street, radio & TV sets at high volume 72 Vacuum cleaners 78 Telephone ring, mechanical workshop 80 Passing trucks, noisy hall or plant, shuffling @ 1 m. 90 Passing train, pneumatic hammer, car hooter @ 1 m. 95 Mega "disco", circular saw 100 Motorcycle without silencer

0 4W power amplifier with 5G37 IC

This circuit requires a voltage of 6-12 Volts. To have a good quality of this series with the voltage necessary suplly good too. The definition of good that is filtered and does not release much ripple voltage and using large-capacity condenser elco issued for the bass is strong enough.

See below this circuit :

Build a Bang Bang Controllers Circuits Wiring diagram

Bang-Bang Controllers Circuits Diagram Just one chip, the PWR-DRV1 from Power Integrations, builds a `bang-bang` controller that switches 275 mA and runs off the rectified 115-Vac mains. An on-chip zener diode powers the chip from high voltage through a dropping resistor.

Bang-Bang Controllers Circuits Diagram

Friday, August 22, 2014

Simple Lamp Dimmer Fan Regulator

This is the schema diagram of the simplest lamp dimmer or fan regulator.The schema is based on the principle of power control using a Triac.

BT 136Triac Necessary Data.

The schema works by varying the firing angle of the Triac . Resistors R1 ,R2 and capacitor C2 are associated with this.The firing angle can be varied by varying the value of any of these components.Here R1 is selected as the variable element .By varying the value of R1 the firing angle of Triac changes (in simple words, how much time should Triac conduct) changes.This directly varies the load power, since load is driven by Triac.The firing pulses are given to the gate of Triac T1 using Diac D1.
Notes

Assemble the schema on a good quality PCB or common board.The load whether lamp ,fan or any thing ,should be less than 200 Watts.To connect higher loads replace the Triac BT 136 with a higher Watt capacity Triac . All parts of the schema are active with potential shock hazard.So be careful.

Parts List

R1 1o K 1 Watt Resistor

R2 1o0 K Potentiometer (Variable Resistance)

C1 0.1 uF (500V or above ) Polyester Capacitor

T1 BT 136 Triac

D1 DB2 Diac

Easy Dc To Dc Converter Wiring diagram Schematic

This Easy Dc To Dc Converter Circuit Diagram uses a Linear Technology LT1073 in a -24-V converter. The supply can be two AA cells (3 V) or 5 V. The schema can deliver 7 mA.

Dc To Dc Converter Circuit Diagram