Power Amp OCL 100W by Transister MJ15003,MJ15004

This Circuit Power Amp OCL 100W by Transister.It old circuit,but nice circuit amplifier.
Use transister MJ15003 and MJ15004, power supply +38V,-38V 3A.
Output power 100W at Speaker 8OHM.

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Power Amp OCL 100W by Transister MJ15003,MJ15004

Power Amp OCL by 741+2N3055+MJ2955

Circuit Power Amp OCL by 741+2N3055+MJ2955

This is old circuit Power amp OCL, But easy circuit and very nice. To use for play music in your home. It low cost too.
It use IC 741 or LF351(good) and Transistor x 4 (2N3055+MJ2955+BD139+BD140)
and little component.
Power supply volt +35V/-35V and 3A for Mono, 5A for Stereo.



PCB Power Amp OCL by 741+2N3055+MJ2955

Circuit Tone control adjustable bass-treble Stereo by IC LM348

Circuit Tone control adjustable bass-treble Stereo by IC LM348
PCB Tone control adjustable bass-treble Stereo by IC LM348

Loudspeaker Protection with Soft Start

This is a small protection circuit from loudspeakers, from DC voltage that likely to exist after some damage in the power amplifier. If a DC voltage is presented in the exit of amplifier, RL1 it interrupts immediately the line of loudspeakers preventing thus to reach in he. Parallel it provides a delay time of 3 seconds from the moment where the power supply will be applied. This delay protects the loudspeakers from undesirable bangs that are observed when open the supply switch. The Leds D 4-5 provide a optical indication for the circuit operation [D4 (green)=OK and D5(red)= delay or presence DC voltage]. The supply of circuit becomes from a symmetrical ±12Volts, which we can take from small independent power supply or from afterwards suitable demotion of main power supply. It will be supposed you make a circuit of protection for each final amplifier that you dispose. Proportional attention it should you show for the quality of RL1 that the contacts of will be supposed to bear the current that passes from he.

Source :: http://users.otenet.gr/~athsam/Lsp_protection.htm

1 Hz Timebase by IC 4017

Circuit 1 Hz Timebase by IC 4017

Circuit 6 DIGIT EVENT COUNTER by IC 4553 + IC 4511

Circuit 6 DIGIT EVENT COUNTER by IC 4553 + IC 4511

10 Hz Timebase by IC 4017

Circuit 10 Hz Timebase by IC 4017

Circuit 3 DIGIT EVENT COUNTER by IC 4553 + IC 4511

Circuit 3 DIGIT EVENT COUNTER by IC 4553 + IC 4511

0-99 counter by IC 4017x2

Circuit 0-99 counter by IC 4017x2

Random number generator by ic 4017

circuit Random number generator by ic 4017

Counter to N and Recycle by IC 4017

circuit Counter to N and Recycle by IC 4017

circuit counter to N and HALT by IC 4017

circuit counter to N and HALT by IC 4017

High power supply regulater 0-30V 20A by LM338

Circuit High power supply regulater 0-30V 20A by LM338

This is High current and Adjustable Volt 0 to 30V 20A.
It easy circuit and nice circuit, Because use IC LM338 and IC 741.
Volt Output adj by VR1-1K.
IC LM338 to hold heat-sink. Transformer is 20A up.

PCB High power supply regulater 0-30V 20A by LM338

TDA2030 amp OTL 15W

Circuit TDA2030 amp OTL 15W
PCB TDA2030 amp OTL 15W

circuit 4-BIT Serial Shift Register by 4027

circuit 4-BIT Serial Shift Register by 4027

circuit 4027 divide by 3 counter

circuit 4027 divide by 3 counter

circuit 4027 divide by 2 counter

circuit 4027 divide by 2 counter

circuit 4013 Divide by 2

circuit 4013 Divide by 2

circuit 4013 Serial IN-OUT, PARALLEL OUT Shift Register

circuit 4013 Serial IN-OUT, PARALLEL OUT Shift Register

circuit 4013 Modula-8-Counter

circuit 4013 Modula-8-Counter

circuit 1 of 4 Seguencer by 4013

circuit 1 of 4 Seguencer by 4013

circuit Programmable Function Generator by 4066 and 4017

circuit Programmable Function Generator by IC CD4017 , CD4066 and NE555

circuit Programmable Gain Amplifier by 4066

circuit Programmable Gain Amplifier by CD4066

Tone Control Stereo (bass-treble) by IC NE5532x2

Circuit Pre Tone Control Stereo (bass-treble) by IC NE5532 x2.
It nice circuit,Volt supply +12V,-12V.

Note : IC NE5532 or LF353 or 4558


PCB Pre Tone Control Stereo (bass-treble) by IC NE5532 x2.

Two HiJack Alarms

Circuit :Ron J
Email Ron:

Description:
The first circuit was designed for the situation where a hijacker forces the driver from the vehicle. If a door is opened while the ignition is switched on - the circuit will trip. After a few minutes delay - when the thief is at a safe distance - the alarm will sound and the engine will fail.

Notes:
You're going to trip this alarm unintentionally. When you do - the LED will light and the Buzzer will give a short beep. The length of the beep is determined by C3. Its purpose is to alert you to the need to push the reset button. When you push the button - the LED will switch-off. Its purpose is to reassure you that the alarm has in fact reset.

If the reset button is not pressed then - about 3 minutes later - both the Siren and the Buzzer will sound continuously. The length of the delay is set by R7 & C4. For extra effect - fit a second siren inside the vehicle. With enough noise going on - you may feel that it's unnecessary to fit the engine cut-out. In which case - you can leave out D8, D9, R11, R12, R13, C6, Q3, Q4 & Ry2.

Even if you missed the early warning provided by the Buzzer - there is still time to reset the alarm before Ry2 de-energizes - and the engine fails. This additional delay - currently about 1 minute - is set by C6 and R13.

To reset the circuit you must - EITHER turn off the ignition - OR close all of the doors - before you press the reset button. While BOTH the ignition is on - AND a door remains open - the circuit will NOT reset.

The reset button carries virtually no current - so any small normally-open switch will do. Eric Vandel from Canada suggests using a reed-switch hidden behind (say) the dash - and operated by a magnet. I think this is an excellent idea. As Eric said in his email: - "... that should keep any thief guessing for a while."

The Flow Chart is another of Eric's suggestions. It will help you to visualize how the alarm is operated. It also explains the sequence of events that lead to siren activation - and subsequent engine failure.

Source:: http://www.zen22142.zen.co.uk/Circuits/Alarm/hijack.htm

TV Transmitter

Circuit :David Kwaku Celestin - Ghana, West Africa
Email :mightycelestin@yahoo.co.uk

Description:
A VHF band TV transmitter using negative sound modulation and PAL video modulation. This is suitable for countries using TV systems B and G.

Notes:
The frequency of the transmitter lies within VHF and VLF range on the TV channel, however this circuit has not been tested at UHF frequencies. The modulated sound signal contains 5.5 -6MHz by tuning C5. Sound modulation is FM and is compatible with UK System I sound. The transmitter however is working at VHF frequencies between 54 and 216MHz and therefore compatible only with countries using Pal System B and Pal System G.

For more information on TV systems visit the links below:
Television Frequency Table

Televison system frequency and channel standards.

Power Supply 0-15V / 1A

R1= 56ohm 2W Q1= 2N3055
R2= 330ohm Lin. pot. T1=220V@18V 1.5A
C1= 2200uF 35V
C2= 100uF 35V D1= 18V 1.5W zener
C3= 10uF 25V
C4= 220uF 25V
C5= 100nF 100V
GR1= 4 X 1N4007

This circuit of power supply, are very simple in the manufacture, the finding of his materials , is very easy and cost, small. The output voltage is stabilised and is regulated in the region from 0V until + 15V dc, with biggest provided current 1 A. The regulation becomes with the R2. The Q1 of is classic power transistor and it needs it is placed in heatsink, one and heating when it works continuously in the region of biggest current. The type of transformer is standard in the market.

LED Voltmeter for car battery by LM324

The circuit, is a comparator, can measure with step of 1Volt, the voltage of battery of car. The clue of voltage become after comparison of voltage of battery, that is applied in the inverting inputs of amplifiers, with voltages of reference that are produced by a Zener D1, the value of which is such so that it present good thermic stability. With the RV1, we regulate the gradation of voltage that we want. The optical clue become from four Led.
R1=1K2 R6=10K D2-3-4-5=LED
R2-3-4=680R R7-8-9-10=1K IC1=LM324
R5=15K D1=5V6 /0.5W Zener RV1=10K trimmer

Source :: http://users.otenet.gr/~athsam/voltmeter_with_led_for_car_battery.htm

Bridge adaptor by NE5534

Read More about Bridge adaptor by NE5534 circuit

Logic probe by IC4050

Circuit Logic probe by IC4050

Increased output drive by IC4050

circuit Increased output drive by IC4050

HA1377 Bridge Amplifier BCL cap 17W (Car audio)

This is circuit Car audio Amplifier(Bridge Amplifier BCL) , It use IC HA1377, Supply Volt 12V-13V. Speaker 4 OHM. Nice Circuit and Easy to Build.

Circuit HA1377 Bridge Amplifier BCL cap 17W


PCB HA1377 Bridge Amplifier BCL cap 17W

Pre Tone Control Stereo (bass-mid range-treble) by IC NE5532

This circuit Tone Control Stereo you can ajustable bass , mid range and treble. It use IC NE5532.
Supply Volt min 12V 80mA .
Easy to build, PCB small.


Circuit Pre Tone Control Stereo (bass-mid range-treble) by IC NE5532

PCB Pre Tone Control Stereo (bass-mid range-treble) by IC NE5532

supply 9VDC no transformer

This is circuiut power supply 9VDC no transformer , It easy circuit and small size.
Circuit supply 9VDC no transformer
PCB supply 9VDC no transformer

Light Relay Switch By BC547 & BC337

This Circuit is easy, Light Relay Switch By BC547 & BC337.
Circuit Light Relay Switch By BC547 & BC337

PCB Light Relay Switch By BC547 & BC337

DC12V to DC50V converter (for car)

Thai circuit for Car audio input battery 12V to 50VDC, It use Transister and IC TL072.

Circuit DC12V to DC50V converter (for car)

PCB DC12V to DC50V converter (for car)

Output expander by IC-4050

Circuit Output expander by IC-4050

output buffer by IC 4050

circuit output buffer by IC 4050

Inverter 100W by IC 4047 + 2N3055

This circuit Inverter input 12V (battery 12V) to out 220V 50HZ, Eesy circuit because less component to use. It use IC 4047 (oscillator 50HZ) and Power Transistor 2N3055 x 2 ,OUTPUT Power 100W.

Read More about : Inverter 100W by IC 4047 + 2N3055

DATA Selector by IC 4066

DATA Selector by IC 4066

IC 4066 DATA BUS CONTROL

Circuit 4066 DATA BUS CONTROL