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uA 741 Pre-amplifier Guitar Schematic

uA 741 Pre-amplifier Guitar Schematic
uA 741 Pre-amplifier Guitar Schematic

A preamplifier ambit acceptable for aerial impedance blazon electric guitar pickups is accustomed here.The ambit is based on a uA 741 op-amp (IC1).The IC1 is active as a non-inverting amplifier.The POT R1 can be acclimated as a aggregate controller.The POT R6 can be acclimated as accent controller.The about-face S1 is acclimated to aftermath “brilliant” or “soft” tonal effects.


* Assemble the ambit on a acceptable affection PCB or accepted board.

* The amplifier can be powered from a 12V array or 12V DC ability supply.

* Up to 24 V DC can be acclimated to ability the circuit.i acclaim 12 V DC.

* The IC 1 should be army on an IC abject .
Read MoreuA 741 Pre-amplifier Guitar Schematic

Nokia N900 User Manual Guide

Nokia N900 Manual – Specs User Guide and Operating Instruction
Tags: Operating Instruction, Owner Manual, Specs, User Guide, User Manual

The Nokia N900 comes with the following specs and features:

* Quad-band EGSM nokia n900 manual specs850/900/1800/1900, WCDMA 900/1700/2100.
* Maemo 5 software and user interface with direct touch logic, 3D accelerated graphics, and multiwindow multitasking menu logic.
* 5 megapixel Carl Zeiss autofocus camera with dual LED flash (4:3 and 16:9 ratio); CMOS sensor, Carl Zeiss optics, Tessar lens 2.8/5.2; Focal length: 5.2; Focus range: 10 cm to infinity.
* 3.5″ touch display with 800 x 480 pixels (WVGA) resolution, 3D Graphics acceleration with support for OpenGL ES 2.0.
* Total available application memory up to 1 GB (256 MB RAM, 768 MB virtual memory). Up to 32 GB internal storage. MicroSD memory card extension, hotswappable, up to 16 GB*
* Form:side-slider
* Dimensions:110.9 x 59.8 x 18 (19.55) mm
* Weight (with battery):181 g.
* Maemo Browser powered by Mozilla technology.
* Integrated A-GPS receiver.
* Bluetooth version 2.1
* Application: Maemo Browser, Phone, Conversations (SMS, Internet Messenger), Contacts, Camera, Photos, Media player, Email, Calendar, Ovi Maps, Clock, Notes, Calculator, PDF reader, File manager, RSS reader, Sketch, Games, Widgets, Application manager for downloads.

The following manual, user guide and operating instruction contain detail information on how to operate, manage, and set up your N900. The manual is divided into sections as follows:
Set up Your Device
Keys and Parts
First Start-up
Use Accessories
Basic Use
Personalize Your Device
Connect Your Device
Browse the Web
organize Your Contacts
Make Calls
Send Instant Messages Mail
Capture Images Record Video Clips
Share Your Image and Video Clips
Play Music and Video Clips
Find and Vies Location (GPS)
Synchronize and Transfer Content
Back up and Restore Data
Update Software and Install Apps
Manage Time
Use Utilities and Manage Data
Play Games
Modify Settings

Get more information on Nokia N900 Manual, Specs, User Guide and Operating Instruction here – free download 4.18 MB PDF file manual from
Read MoreNokia N900 User Manual Guide

Skema Rangkaian Gitar Ibanez

Skema Rangkaian Gitar Ibanez
2008 ART Ibanez Wiring Diagram

The following schematic shows 2008 ART Ibanez Wiring Diagram which consists of neck pickup, bridge pickup, neck volume 50K-B, bridge volume 50K-B, 3way-toggle, tone, output, and battery box.

Read MoreSkema Rangkaian Gitar Ibanez

Telephone Audio Interface Circuit

Audio from a blast band can be acquired application a agent and capacitor to abstract the band from alien equipment. A non-polarized capacitor is placed in alternation with the agent band affiliation to anticipate DC accepted from abounding in the agent ambagious which may anticipate the band from abiding to the on-hook state. The capacitor should accept a voltage appraisement aloft the aiguille arena voltage of 90 volts additional the on-hook voltage of 48 volts, or 138 volts total. This was abstinent locally and may alter with location, a 400 volt or added appraisement is recommended. Audio akin from the agent is about 100 millivolts which can be affiliated to a aerial impedance amplifier or band recorder input. The 3 transistor amplifier apparent aloft can additionally be used. For overvoltage protection, two diodes are affiliated beyond the agent accessory to absolute the audio arresting to 700 millivolts aiguille during the campanology signal. The diodes can be best any silicon blazon (1N400X / 1N4148 / 1N914 or other). The 620 ohm resistor serves to abate loading of the band if the achievement is affiliated to a actual low impedance.

Telephone Audio Interface Circuit

Telephone Audio Interface Circuit
Read MoreTelephone Audio Interface Circuit

Rangkaian Pasif Crossover

Rangkain Pasif Crossover
Rangkain Pasif Crossover

A passive crossover has no active filters as were used in the electronic crossover. It uses coils (inductors) and capacitors to cause a rolloff of the audio level. The simplest types use a single coil OR capacitor connected in series with the speaker. If a capacitor is used, it will reduce the lower frequencies getting through to the speaker. If an inductor is used, it will reduce the higher frequencies getting through to the speaker. In this configuration, the rate of rolloff is 6dB/octave. In a more complex configuration combining both coils and capacitors on each speaker, a steeper rolloff is obtainable.
Read MoreRangkaian Pasif Crossover

Solar Charge Controller Circuit

Solar Charge Controller Circuit
Solar Charge Controller Circuit

The antecedent adaptation of this accessory acclimated beating amplitude accentuation (pwm) to ascendancy the ability from the bristles solar panels to allegation the array bank. Under abounding sun altitude the MOSFETS got a bit balmy and the accomplished assemblage broadcast a lot of RFI. This architecture uses a set of relays - one for anniversary panel. If the ambassador decides the array voltage is too low, it engages addition relay; if its too high, it drops one out. This tends to 'float' the voltage at about 14 volts as continued as acceptable sunlight is available.

The ambassador additionally accouterments a arrangement appearance interface (open beneficiary TTL, 9600 baud). This makes it accessible to 'tweak' the allegation settings application a terminal affairs and an RS-232 to TTL interface (coming to this web armpit soon). If you accept to alike this device, you may leave out the arrangement being and 'hardwire' the allegation settings in software.
Read MoreSolar Charge Controller Circuit

VGA/Video Adapter Circuit Schematic

VGA/Video Adapter Schematic
VGA/Video Adapter Schematic

VGA/Video Adapter  Circuit
VGA/Video Adapter Circuit

Quantity of symbols: 20 lines by 20 characters.
The resolution of a character matrix: 8x12 points
Supported code page: WIN 1251
Formed signal: VGA
The resolution: 640x480
Frequency of vertical synchronization: 60Hz
Speed of exchange UART 19200 bps

Video terminal:
Quantity of symbols: 20 lines by 38 characters.
The resolution of an individual character matrix: 8x12 points
Supported code page: WIN 1251
Formed signal: Composite Video (PAL/SECAM)
Resolution: 625 lines (interlaced)
Frequency of vertical synchronization: 50Hz
Speed of exchange UART 19200 bps

Type of the used microcontroller: Mega8, Mega16, Mega32, Mega8535, etc.

Clock frequency of the microcontroller standard - 16Mhz.

1. To avoid distortion of the image, when receiving data through the UART, for VGA, it is recommended to make the data exchange with the terminal in approximately 300-600 us after a signal of vertical synchronization (VSYNC).
2. The available internal RAM of the Mega8535 (only 512 bytes) is not enough for the formation of a Video signal with a resolution of 38x20 symbols.
Read MoreVGA/Video Adapter Circuit Schematic

Rangkaian Delay Dan Relay

Rangkaian Delay Dan Relay
Delay and Relay Circuit

This ambit waits for a set time and again activates a relay.

With the cap that is in the schematic you will get about a 6 sec adjournment till ability on. You can change the cap in this ambit to 470uF for about a 20 sec delay.

Delay and Relay Part list

2 x resistor

3 x transistor

1 x diode

1 x capacitor

1 x relay

Misc some wire, a board, etc.

Read MoreRangkaian Delay Dan Relay

Rangkaian Switching Power Supply Sederhana


• Simple high-efficiency step-down (buck) regulator
• Efficient pre-regulator for linear regulators
• On-card switching regulators
• Positive to negative converter (Buck-Boost)


• 3.3V, 5V, 12V, 15V, and adjustable output versions
• Adjustable version output voltage range,
 1.23V to 37V (57V for HV version) ±4% max over
 line and load conditions
• Guaranteed 1A output current
• Wide input voltage range, 40V up to 60V for HV version
• Requires only 4 external components
• 52 kHz fixed frequency internal oscillator
• TTL shutdown capability, low power standby mode
• High efficiency
• Uses readily available standard inductors
• Thermal shutdown and current limit protection
• P + Product Enhancement tested

Rangkaian Switching Power Supply Sederhana

LM2575 series of regulators are monolithic integrated circuits that provide all the active functions for a step-down (buck) switching regulator, capable of driving a 1A load with excellent line and load regulation. These devices are available in fixed output voltages of 3.3V, 5V, 12V, 15V, and an adjustable output version.

Requiring a minimum number of external components, these regulators are simple to use and include internal frequency compensation and a fixed-frequency oscillator.

The LM2575 series offers a high-efficiency replacement for popular three-terminal linear regulators. It substantially reduces the size of the heat sink, and in many cases no heat sink is required.

A standard series of inductors optimized for use with the LM2575 are available from several different manufacturers. This feature greatly simplifies the design of switch-mode power supplies.

Other features include a guaranteed ±4% tolerance on output voltage within specified input voltages and output load conditions, and ±10% on the oscillator frequency. External shutdown is included, featuring 50 μA (typical) standby current. The output switch includes cycle-by-cycle current limiting, as well as thermal shutdown for full protection under fault conditions.
Read MoreRangkaian Switching Power Supply Sederhana

One TV Scanline Memory Buffer

This technique started on idea that VGA screen at 640x480 resolution is non-interlaced picture 60 Hz refresh rate and horizonal scan frequency of 2xNTSC horizonal scan frequency. The converter needed to convert this to interlaced TV signals has to do the following things:

  • Store first odd number scanline shown in VGA screen
  • Send out the stored can line at half speed and encode it to NTSC video signal
  • Store next odd scanline to buffer
Using this method the whole picture is converted to TV screen. When all odd lines are handle in one picture, the even number scan lines are handled in the same way on next round. This method gives out nice interlaced NTSC TV picture from 640x480 VGA screen. The picture below is a block diagram of one way to do this conversion:

Block diagram

The converter handles 640x480 graphics nicely without any drivers and it is possible to have your VGA monitor showing the same picture at the same time. To ble able to show other VGA resolutions nicely a driver is need to set all VGA modes to 60 Hz refresh rate (the driver makes VGA card to add blank scanlines to the beginning and end of the picture to make it 480 line picture).

When conversion is needed for PAL TV, a driver is needed which sets all VGA modes to 50 Hz operation. The horizonal scan rate for PAL output is still made by halving the VGA horizonal scan rate, which gives a little bit too high horizonal scan rate for output PAL signal. This problem usually messes up the colors in many products (for proper PAL signal decoding the horizonal scan rate must be very accurately right in conjuction with the color subcarrier frequency).

The electronics itself become quite complicated. A typical circuit which connnect to VGA monitor output needs fast A/D converters for digitizing incoming video signal, small memory biffer for storing those signals and digital PAL/NTSC encoder. Because the basic conversion need quite much electronics, the manufacturers have typically added a flicker reducing circuits to their products. Flicker reduction circuit stores fre scanlines information and interpolate between those scanlines to get rid of some of the flickering. There are some special ICs in the marked which can do all this.

Application fields where this technique is used: Most inexpensive small external VGA to TV converters, VGA chipsets with built-in TV output

Read MoreOne TV Scanline Memory Buffer

Karakteristik Sistem B,G/PAL dan M/NTSC Pada TV

Basic Characteristics

Basic characteristics of video and synchronizing signals
Number of lines per picture (frame)
Field frequency, nominal value (fields/s)
Line frequency fH
Assumed gamma of display device
Nominal video bandwidth (MHz)

Line Synchronizing Signal

Nominal and peak levels of the composite video signal (%)
Durations measured between half-amplitude points on the approriate edges
Symbol Characteristics
Blanking level
Peak white-level
Synchronizing level
Difference between black and blanking levels
Peak-to-peak value of burst
Peak level including chrominance signal

Details of line synchronizing signals
Build-up times measured between 10% to 90% of the pulse edges
Symbol Characteristics
Nominal line period (µs)
Line-blanking interval (µs)
Interval between time datum (0H) and back edge of line-blanking pulse (µs)
9.2 to 10.3
Front porch (µs)
1.27 to 2.22
Synchronizing pulse (µs)
Build-up time of the line blanking pulse (µs)
Build-up time of the line synchronizing pulse (µs)
Start of sub-carrier burst (µs)
5.3 (4.71 to 5.71)
Duration of sub-carrier burst (µs)
2.25±0.23 (10±1 cycles)
2.23 to 3.11(9±1 cycles)

Field Synchronization of PAL System

Details of B,G/PAL field synchronizing signals
Durations measured between half-amplitude points on the approriate edges
Build-up times measured between 10% to 90% of the pulse edges
Symbol Characteristics
Field Period (ms)
Field-blanking interval
25 H + a
Build-up time of the edges of field-blanking pulse (µs)
Interval between front edge of field-blanking interval and front edge of first equalizing pulse (µs)
Duration of first sequence of equalizing pulses
2.5 H
Duration of sequence of synchronizing pulses
2.5 H
Duration of second sequence of equalizing pulses
2.5 H
Duration of equalizing pulses (µs)
Duration of field-synchronizing pulses (µs)
Interval between field-synchronizing pulses (µs)
Build-up time of synchronizing and equalizing pulses (µs)

Field Synchronization of NTSC System

Details of M/NTSC field synchronizing signals
Durations measured between half-amplitude points on the approriate edges
Build-up times measured between 10% to 90% of the pulse edges
Symbol Characteristics
Field Period (ms)
Field-blanking interval
(19 to 21) H + a
Build-up time of the edges of field-blanking pulse (µs)
Interval between front edge of field-blanking interval and front edge of first equalizing pulse (µs)
Duration of first sequence of equalizing pulses
3 H
Duration of sequence of synchronizing pulses
3 H
Duration of second sequence of equalizing pulses
3 H
Duration of equalizing pulses (µs)
Duration of field-synchronizing pulses (µs)
Interval between field-synchronizing pulses (µs)
Build-up time of synchronizing and equalizing pulses (µs)

Radiated Signal

Characteristics of the radiated signal
Levels in this table are % of peak carrier.
Nominal RF channel bandwidth (MHz)
Sound carrier relative to vision carrier (MHz)
Nearest edge of channel relative to vision carrier (MHz)
Nominal width of main sideband (MHz)
Nominal width of vestigial sideband (MHz)
Type and polarity of vision modulations
C3F neg.
C3F neg.
Synchronizing level (%)
Blanking level (%)
72.5 to 77.5
Difference between black level and blanking level (%)
0 to 2
2.88 to 6.75
Peak white level (%)
10 to 15
10 to 15
Type of sound modulation
Frequency deviation (kHz)
Pre-emphasis for modulation (µs)
Read MoreKarakteristik Sistem B,G/PAL dan M/NTSC Pada TV

Rangkaian Switch 8 Ampere

The ambit in Fig 1 delivers 8A for active as abounding as two of today's high-performance, accelerated µPs. You can additionally optimize the architecture for lower accepted by alteration a few components. Most systems use a low-current 12V bent accumulation and a ailing adapted high-current 5V to ability the logic. However, the µP requires 3.3V for its capital ability voltage. Thus, an able dc/dc advocate that can catechumen 5 to 3.3V and accommodate a deeply adapted achievement voltage is necessary. The primary architecture objectives for this ambit were aspersing cost, eliminating the charge for calefaction sinks, and accouterment circumlocute aegis to aerate reliability.

A step-down (buck) regulator that operates at 80 kHz provides the 3.3V/8A output. IC1 drives the capital switching transistor, the N-channel Q3, through the Q1 and Q2 gate-drive transistors. Active drive for the aboideau of Q3 is all-important to aftermath actual fast switching transitions, which abbreviate switching losses.

The open-collector achievement of IC1's PWM dent controls Q1 and Q2. Back pin 6 pulls low, Q1 turns on through R9, and Q2 turns off, because D1 holds Q2's abject high. This activity pulls Q3's FET about-face up to 12V, which turns on Q3. Back pin 6 of IC1 is high, R7 turns on Q2, and R8 turns off Q1. In this state, the ambit pulls Q3's aboideau to ground, which turns it off. Q3, bolt diode D2, L1, C12, and C13 accommodate a dc achievement able of sourcing 8A of bulk current.

Note that you can use an 8A diode for D2 with alone a slight access in ability amusement in this device. Also, you can use a distinct 4700-µF achievement capacitor at the regulator achievement if achievement ripple and brief acknowledgment are not critical.

IC2, a attention advertence whose setpoint voltage is 3.3Vñ0.5%, provides acknowledgment and voltage control. Back the regulator achievement alcove 3.3V, IC2 sources accepted through R2 to ground, accouterment acknowledgment to the ascribe of IC1 and captivation the regulator achievement at 3.3V.

IC1 and faculty resistor R5 calmly apparatus overcurrent protection. Back the voltage bead beyond R5 exceeds 110 mV, IC1 activates its congenital pulse-by-pulse control, which banned the achievement current. R5 consists of a allotment of AWG 17 attrition wire (type MWS-294: MWS Industries, West Lake, CA, (818) 991-8553) with an able breadth of 1.5 in. You can additionally body R5 application the aforementioned breadth and barometer of manganin wire.

C16 charge sit actual abreast the cesspool of Q3, and C16's agnate alternation attrition (ESR) is critical. Do not acting a capacitor with college ESR. The aforementioned admonishing applies to C12 and C13 Booty affliction to analysis ESR specs if you use a substitute.

R1, R3, C3, and C6 set the bend advantage of IC1; C7 sets the oscillator frequency. C7 should be a acceptable affection bowl capacitor. C1, C2, C4, and C8 are all-important for ascribe bypassing, and they abate the bulk of switching babble the ambit conducts assimilate the ascribe lines. A snubber consisting of R10 and C10 is all-important to annihilate high-frequency campanology back Q3 switches off. These apparatus charge be amid as abutting as accessible to Q3. R13 and C17 accomplish the aforementioned action for D2.

Bench testing indicates the afterward ambit performance. For VIN5V, ability was 88% for a bulk accepted of 4A and 84% for a bulk accepted of 8.2A. For VIN5V and ILOAD8.2A, babble was 15-mV p-p and 5.5-mV rms application an HP34401A meter. The switcher backward in adjustment with no changes in the achievement voltage (1-mV altitude accuracy) back the bulk assorted from 0.1 to 8A and back the ascribe voltage assorted from 4.5 to 5.5V. With no calefaction sinks or airflow, the temperature of Q3 was 70øC and of D2 was 50øC, back operating at 8.2A connected bulk current.

All high-current switchers are acute to lath layout; booty affliction back designing the pc board. You'll access the best after-effects by application a multilayer board, so you can address a distinct band to arena plane. You should tie the "power" apparatus (C1, C2, C16, D2, C12, C13, C14) anon to this arena even and accumulation these apparatus so that the affiliation paths are as abbreviate as possible. You should affix the low-current ground, as Fig 1 shows, and again tie it to the ability arena at a distinct point abreast C13. Finally, all traces in the switching ability aisle (R5, Q3, and L1) charge be as abbreviate as possible. (DI #1688)

Rangkaian Switch 8 Ampere

Read MoreRangkaian Switch 8 Ampere

Rangkaian Crossover Aktif 2 Jalur

This alive Cantankerous over is adequately beeline forward. It consists of a absorber and two 3rd order, 18 dB per octave filters. One low canyon and the added high. The cantankerous over abundance is set at 2Khz and is advised for AEK's 400watt per access PA/Keyboard Amp systems. Obviously alone one access is apparent here.

The band akin audio arresting enters the absorber area it is astern out of phase. This is to atone for the filters which will alter the appearance afresh appropriately abiding the arresting to it's able phase. The filters are more-or-less accepted low and aerial canyon filters appropriately however, added capacitors and resistors accept been added in adjustment to get the altruism bottomward to a minimum appliance alone E12 components.

This ambit may not be of awfully abundant use to anyone as it was accurately advised to clothing the applications. It is not capricious or switchable for two reasons. Firstly, it didn't charge to be back the backdrop of the apostle arrangement were already known. And secondly, the added complication was put into the accurateness of the crossover rather than it's flexibility. The filters are akin in account to anniversary added as able-bodied as can be accepted appliance alone E12 components. If switching were to be active to accord a ambit of abundance options, a accommodation would accept to be fabricated on clarify accuracy.

The alone added way to accomplish a accepted crossover architecture and advance accurateness would apparently be to use Switched capacitor clarify architecture blocks. In theory, two 18or 24dB per octave filters could be complete such that they tracked anniversary added by actuality bound to the aforementioned clock. This would be a nice agreement but I haven't had the befalling to prove this technology for this affectionate of application. My primary affair was the breach through of switching babble appliance such a design.

Therefore this architecture represents the simplest access I could booty and still get the adapted outcome.

Rangkaian Crossover Aktif 2 Jalur
Rangkaian Crossover Aktif
Read MoreRangkaian Crossover Aktif 2 Jalur

Rangkaian Amplifier Gitar Bass Sederhana

Bass Guitar Amplifier Parts:

P1______________1M Linear Potentiometer
P2____________100K Log Potentiometer

R1_____________68K 1/4W Resistor
R2____________470K 1/4W Resistor
R3______________2K7 1/4W Resistor
R4______________8K2 1/4W Resistor
R5____________680R 1/4W Resistor
R6____________220K 1/4W Resistor
R7_____________39R 1/4W Resistor
R8______________2R2 1/4W Resistor
R9____________220R 1/4W Resistor
R10_____________1R 1/4W Resistor
R11___________100R 1/2W Resistor
R12_____________1K5 1/4W Resistor

C1____________100pF 63V Polystyrene or Ceramic Capacitor
C2,C5,C9,C14__100nF 63V Polyester Capacitors
C3____________100µF 25V Electrolytic Capacitor
C4_____________47µF 25V Electrolytic Capacitor
C6______________4n7 63V Polyester Capacitor
C7____________470pF 63V Polystyrene or Ceramic Capacitor
C8______________2µ2 25V Electrolytic Capacitor
C10___________470µF 25V Electrolytic Capacitor
C11____________22nF 63V Polyester Capacitor
C12__________2200µF 25V Electrolytic Capacitor
C13__________1000µF 25V Electrolytic Capacitor

D1______________3mm red LED

Q1____________BF245 or 2N3819 General-purpose N-Channel FET

IC1_________TDA2003 10W Car Radio Audio Amplifier IC

SW1,SW2________SPST toggle or slide Switches

J1____________6.3mm Mono Jack socket
J2____________6.3mm Stereo Jack socket (switched)
J3_____________Mini DC Power Socket

SPKR__________4 Ohm Car Loudspeaker 100 or 130mm diameter

Bass Guitar Amplifier Technical data:

Output power (1KHz sinewave):
6W RMS into 4 Ohm at 14.4V supply
50mV RMS input for full output
Frequency response:
25Hz to 20kHz -3dB with the cursor of P1 in center position
Total harmonic distortion:
0.05 - 4.5W RMS: 0.15% 6W RMS: 10%
Read MoreRangkaian Amplifier Gitar Bass Sederhana

Rangkaian Amplifier Gitar Portabel

Portable Guitar Amplifier Circuit Parts:

R1______________22K 1/4W Resistor

C1______________10µF 25V Electrolytic Capacitor
C2_____________100nF 63V Polyester or Ceramic Capacitor
C3_____________220µF 25V Electrolytic Capacitor

IC1__________TDA7052 Audio power amplifier IC

J1,J2__________6.3mm Stereo Jack sockets (switched)

SPKR___________8 Ohm Loudspeaker (See Notes)

B1________________9V PP3 Battery or
3V Battery (2 x 1.5V AA, AAA Cells in series etc.)

Clip for PP3 Battery or socket for 2 x 1.5V AA or AAA Cells

Portable Guitar Amplifier Technical data:

Max output power: 1.5W @ 9V supply - 8 Ohm load; 60mW @ 3V supply - 8 Ohm load

Frequency response: Flat from 20Hz to 20kHz

Total harmonic distortion @ 100mW output: 0.2%

Max input voltage @ 3V supply: 8mV RMS

Minimum input voltage for Fuzz-box operation: 18mV RMS @ 3V supply

Current consumption @ 400mW and 9V supply: 200mA

Current consumption @ 250mW and 9V supply: 150mA

Current consumption @ 60mW and 3V supply: 80mA

Quiescent current consumption: 6mA @ 9V, 4mA @ 3V supply

Fuzz-box current consumption: 3mA @ 3V supply
Read MoreRangkaian Amplifier Gitar Portabel

Rangkaian Pengatur Temperatur Kipas angin

Rangkaian Pengatur Temperatur Kipas angin Parts:

P1_____________22K Linear Potentiometer (See Notes)

R1_____________15K @ 20°C n.t.c. Thermistor (See Notes)
R2____________100K 1/4W Resistor
R3,R6__________10K 1/4W Resistors
R4,R5__________22K 1/4W Resistors
R7____________100R 1/4W Resistor
R8____________470R 1/4W Resistor
R9_____________33K 4W Resistor

C1_____________10nF 63V Polyester Capacitor

D1________BZX79C18 18V 500mW Zener Diode
D2_________TIC106D 400V 5A SCR
D3-D6_______1N4007 1000V 1A Diodes

Q1,Q2________BC327 45V 800mA PNP Transistors
Q3___________BC337 45V 800mA NPN Transistor

SK1__________Female Mains socket

PL1__________Male Mains plug & cable

R3-R4 and P1-R1 are active as a Wheatstone arch in which R3-R4 accomplish a anchored two-thirds-supply "reference" voltage, P1-R1 accomplish a temperature-sensitive "variable" voltage, and Q1 is acclimated as a arch antithesis detector.

P1 is adapted so that the "reference" and "variable" voltages are according at a temperature aloof beneath the appropriate activate value, and beneath this action Q1 Base and Emitter are at according voltages and Q1 is cut off. When the R1 temperature goes aloft this "balance" amount the P1-R1 voltage avalanche beneath the "reference" value, so Q1 becomes advanced biased, pulse-charging C1.

This occurs because the accomplished ambit is supplied by a 100Hz half-wave voltage acquired from mains accumulation by agency of D3-D6 diode arch after a cutting capacitor and anchored to 18V by R9 and Zener diode D1. Therefore the 18V accumulation of the ambit is not accurate DC but has a rather trapezoidal shape. C1 provides a capricious phase-delay pulse-train accompanying to temperature and ancillary with the mains accumulation "zero voltage" point of anniversary bisected cycle, appropriately bearing basal switching RFI from the SCR. Q2 and Q3 anatomy a activate device, breeding a abbreviate beating acceptable to drive the SCR.
Read MoreRangkaian Pengatur Temperatur Kipas angin

Rangkaian Digital Remote Kontrol Termometer

Transmitter ambit operation:

IC1 is a attention centigrade temperature sensor with a beeline achievement of 10mV/°C active IC2, a voltage-frequency converter. At its achievement pin (3), an ascribe of 10mV is adapted to 100Hz abundance pulses. Thus, for example, a temperature of 20°C is adapted by IC1 to 200mV and again by IC2 to 2KHz. Q1 is the disciplinarian of the ability achievement transistor Q2, accompanying to the mains accumulation by L1 and C7, C8.

Transmitter parts:

R1,R3________100K  1/4W Resistors
R2___________47R 1/4W Resistor
R4____________5K 1/2W Trimmer Cermet
R5___________12K 1/4W Resistor
R6___________10K 1/4W Resistor
R7____________6K8 1/4W Resistor
R8,R9_________1K 1/4W Resistors

C1___________220nF 63V Polyester Capacitor
C2____________10nF 63V Polyester Capacitor
C3_____________1µF 63V Polyester Capacitor
C4,C6__________1nF 63V Polyester Capacitors
C5_____________2n2 63V Polyester Capacitor
C7,C8_________47nF 400V Polyester Capacitors
C9__________1000µF 25V Electrolytic Capacitor

D1__________1N4148 75V 150mA Diode
D2,D3_______1N4002 100V 1A Diodes
D4____________5mm. Red LED

IC1___________LM35 Linear temperature sensor IC
IC2__________LM331 Voltage-frequency converter IC
IC3__________78L06 6V 100mA Voltage regulator IC

Q1___________BC238 25V 100mA NPN Transistor
Q2___________BD139 80V 1.5A NPN Transistor

L1___________Primary (Connected to Q2 Collector): 100 turns
Secondary: 10 turns
Wire diameter: O.2mm. enameled
Plastic former with ferrite core. Outer diameter: 4mm.

T1___________220V Primary, 12+12V Secondary 3VA Mains transformer

PL1__________Male Mains plug & cable

Receiver ambit operation:

The abundance pulses advancing from mains accumulation and cautiously cloistral by C1, C2 & L1 are amplified by Q1; diodes D1 and D2 attached peaks at its input. Pulses are filtered by C5, boxlike by IC1B, disconnected by 10 in IC2B and beatific for the final calculation to the alarm ascribe of IC5.

IC4 is the time-base generator: it provides displace pulses for IC1B and IC5 and enables latches and gate-time of IC5 at 1Hz frequency. It is apprenticed by a 5Hz aboveboard beachcomber acquired from 50Hz mains abundance picked-up from T1 secondary, boxlike by IC1C and disconnected by 10 in IC2A.

IC5 drives the displays' cathodes via Q2, Q3 & Q4 at a multiplexing amount abundance anchored by C7. It drives additionally the 3 displays' paralleled anodes via the BCD-to-7 articulation decoder IC6.

Summing up, ascribe pulses from mains accumulation at, say, 2KHz frequency, are disconnected by 10 and displayed as 20.0°C.

Receiver Parts:

R1__________100K   1/4W Resistor
R2____________1K 1/4W Resistor
R3,R4,R6-R8__12K 1/4W Resistors
R5___________47K 1/4W Resistor
R9-R15______470R 1/4W Resistors
R16_________680R 1/4W Resistor

C1,C2_________47nF 400V Polyester Capacitors
C3,C7__________1nF 63V Polyester Capacitors
C4____________10nF 63V Polyester Capacitor
C5,C6,C10____220nF 63V Polyester Capacitors
C8__________1000µF 25V Electrolytic Capacitor
C9___________100pF 63V Ceramic Capacitor

D1,D2,D5____1N4148 75V 150mA Diodes
D4,D4_______1N4002 100V 1A Diodes
D6-D8_______Common-cathode 7-segment LED mini-displays

IC1__________4093 Quad 2 input Schmitt NAND Gate IC
IC2__________4518 Dual BCD Up-Counter IC
IC3__________78L12 12V 100mA Voltage regulator IC
IC4__________4017 Decade Counter with 10 decoded outputs IC
IC5__________4553 Three-digit BCD Counter IC
IC6__________4511 BCD-to-7-Segment Latch/Decoder/Driver IC

Q1___________BC239C 25V 100mA NPN Transistor
Q2-Q4________BC327 45V 800mA PNP Transistors

L1___________Primary (Connected to C1 & C2): 10 turns
Secondary: 100 turns
Wire diameter: O.2mm. enameled
Plastic former with ferrite core. Outer diameter: 4mm.

T1___________220V Primary, 12+12V Secondary 3VA Mains transformer

PL1__________Male Mains plug & cable

Read MoreRangkaian Digital Remote Kontrol Termometer

Xerox Printer Phaser 2135 Wiring Diagram

Xerox Printer Phaser 2135 Wiring Diagram
Xerox Printer Phaser 2135 Wiring Diagram

The afterward printer base diagram applies for Xerox Phaser 2135 series. Herein you will get detail analogy of the electrical schematics, and description of the base affiliation amid genitalia e.g. wire acquisition at the agent ambassador board, array affairs thru EMI coils, avenue base accouter thru cable, avenue of base accouter thru cable catch and capacity of base passthru of the printer. Note: Ensure the base accouter are baffled central the base absorber except the ability base harness; ensure the ability accouter inter-connect is dressed abaft the collapsed award cables to ensure it does not abstract back the top awning is bankrupt and accomplish abiding the base is not pitched by the top absorber bowl back it is installed.

Find detail of Xerox Phaser 2135 Printer Wiring Diagram here.
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Nokia N91 Repir Manual with Circuit Schematic Diagram

Nokia N91 Circuit Schematic Diagram
Nokia N91 Repir Manual with Circuit Schematic Diagram

The afterward chiral accommodate detail advice about Nokia N91 Wiring Diagram and Electrical Schematic for Adjustment and Troubleshooting. The purpose of this certificate is to accommodate added abstruse adjustment advice for Nokia adaptable phone. It contains added advice such as e.g. "Component Finder". The "Signal Overview" folio gives and fast overview about the best important signals and voltages on board. This chiral is disconnected into sections as follows: Front Folio (exploded view), System Connector, RETU, TAHVO, RAP3G, Memories, OMAP, Memory, Camera, HDD, WLAN, BT, FM-radio, Audio-DAC, UI, RF-part, Signal Overview and Component Finder.

Find more information about Nokia N91 Wiring Diagram and Electrical Schematic for Repair and Troubleshooting here – free download PDF file from
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Skema Rangkaian HP Nokia N-Gage

Skema Rangkaian HP Nokia N-Gage
Nokia N-Gage Circuit Diagram and Schematics

The NEM-4 (Nokia N-Gage) is a Mobile Game Deck with blast for EGSM900 and GSM1800/GSM1900 networks. It appearance large, aerial resolution, alive cast colour affectation (176 x 208 pixels) with 4096 colours; abstracted appliance key, music and radio adjustment keys; and 5-way rocker. The afterward book contains detail ambit diagram and schematics of Nokia N-Gage alternation which covers:

"Connections amid RF and BB modules, NEM-4 BB, UPP_WD2 NEM-4, ability circuit, NEM-4 AUX Power, UEM, Audio, ADSP and FLASH, FM Radio and Audio Codec, Memories, User Interface, keypad, Card and USB Interface, Accessory Interface, System Connector, LPRF BT102, Test Interface, GSM BB-RF Interface, Connectors Amid RF Modules, Ability Amplifier, Mjoelner, Testpoints, Component Placement Diagram Bottom, Component Placement Diagram Top."

Get more information about Nokia N-Gage Circuit Diagram and Schematics here – free download 1.4MB PDF file manual. (source:
Read MoreSkema Rangkaian HP Nokia N-Gage

Cara Membuat LoudSpeaker

The Jasper Circle Jig: A lifesaver!

Drilling guide holes for the jig's pivot pin.

Left: The jig goes for a spin atop a fascia panel.
Right: A milled fascia piece showing holes plus countersinks. Note the dog-ears manually rasped into the tweeter hole to account for its side-mounted terminals. This was not mentioned in the instructions, which seemed to have been written long ago, and on several occasions didn't fully account for the peculiarities of the included parts. But half the fun is wingin' it.

Gluing and clamping the fascia.

Matte black spray paint for the fascia and black panels. In the end, getting an acceptably smooth finish required two coats of spray primer and a couple of coats of black enamel.

Prep for assembly includes dry-fitting all the pieces and tweaking panels as needed for a perfect fit.

For efficiency, assembly involves gluing and clamping the panels together with butt joints, then putting in temporary drywall screws to keep the glue joints tight while you remove the clamps and move on to the next panel. After the glue drys, the screws come out and the holes and countersinks are filled with wood putty.

Box assembly.

Visit Here to More Info About How To Make Your Own Speaker:

Step-by-Step Construction Guide with Photos >>>

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Skema Rangkaian LM386 Mini Amplifier

This is one of my favorites. The LM386 is a low voltage audio ability amplifier. It can accommodate 125mW to 750mW, abundant for any activity that uses audio. This ambit can assignment with batteries, requieres minimum alien genitalia and works from 4 to 18 Volts (contact the architect or apprehend the abstruse info. Some versions works alone with 5 to 15V.)

The ability achievement depends of the voltage. The ability achievement is 125mW back the voltage is 6V. The voltage accretion goes from 20 to 200 and the achievement is self-centering, so doesn't charge bifold voltage as added amplifiers. It can be acclimated on array radios, band players, intercoms, also, as accelerated amplifier. This dent is the "555" of the amplifiers.

Taken from

Here is the archetypal appliance for this chip. Here are two schematics, the aboriginal one accept a accretion of 200 and the additional one is alone 20. You can use a about-face for the 10uF capacitor to accept the "boost" option.

The 10k resistor is acclimated to acclimatize the affection if the electret microphone, the 100k resistor is acclimated to acclimatize the volume.

In theory, this ambit will not assignment because it needs a pre-amplifier. Supposedly, a 741 or any othe pre-amplifier is needed. As I said before, I don't chase the theory. I already absolute that the pre-amplifier is not needed, aloof acclimatize the 10k capricious resistor. In fact, You may not be able to get the ambit to assignment appropriately with a pre-amplifier.

Read MoreSkema Rangkaian LM386 Mini Amplifier


This circuit uses a single chip, IC BA3812L for realizing a 5 band graphic equalizer for use in hi-fi audio systems.The BA3812L is a five-point graphic equalizer that has all the required functions integrated onto one IC. The IC is comprised of the five tone control circuits and input and output buffer amplifiers. The BA3812L features low distortion, low noise, and wide dynamic range, and is an ideal choice for Hi-Fi stereo applica-tions. It also has a wide operating voltage range (3.5V to 16V), which means that it can be adapted for use with most types of stereo equipment.

The five center frequencies are independently set using external capacitors, and as the output stage buffer amplifier and tone control section are independent circuits, fine control over a part of the frequency bandwidth is possible, By using two BA3812Ls, it is possible to construct a 10-point graphic equalizer. The amount of boost and cut can be set by external components.

The recommended power supply is 8V, but the circuit should work for a supply of 9V also. The maximum voltage limit is 16V.

The circuit given in the diagram operates around the five frequency bands:

* 100Hz
* 300Hz
* 1kHz
* 3kHz
* 10kHz


Here is a versatile circuit of IF signal generator which may be of interest to radio hobbyists and professionals alike.Transistors T1 and T2 form an astable multivibrator oscillating in the audio frequency range of 1 to 2 kHz. RF oscillator is built around transistor T3. Here again a 455kHz ceramic filter/resonator is employed for obtaining stable IF. The AF from multivibrator is coupled from collector of transistor T2 to emitter of transistor T3 through capacitor C3. The tank circuit at collector of transistor T3 is formed using medium wave oscillator coil of transistor radio, a fixed 100pF capacitor C5 and half section of a gang capacitor (C6).

The oscillator section may be easily modified for any other intermediate frequency by using ceramic filter or resonator of that frequency and by making appropriate changes in the tank circuit at collector of transistor T3. Slight adjustment of bias can be affected by varying values of resistors R6 and R7, if required


Described here is a very inexpensive solution to many phono-controlled applications like remote switching on, for instance, or activating a camera, tape recorder, burglar alarms, toys, etc. The circuit given here employs a condenser microphone as the pick-up. A two-stage amplifier built around a quad op-amp IC LM324 offers a good gain to enable sound pick-up upto four metres. The third op-amp is configured as a level detector whose non-inverting terminal is fed with the amplified and filtered signal available at the output of the second op-amp. The inverting input of the third op-amp is given a reference voltage from a potential divider consisting of a 10k resistor and a 4.7k preset. The 100-ohm resistance in series with the potential divider ensures against the mis-triggering of the circuit by noise. Thus by adjusting the preset one can control the sensitivity (threshold) of the circuit. The sensitivity control thus helps in rejecting any external unwanted sounds which may be picked up by the amplifier. The output of the level detector are square pulses which are used to trigger a flip-flop. The 100mF capacitor connected across the supply also helps in bypassing noise.
A well regulated supply is recommended for proper functioning of the circuit because an unregulated supply can cause noise pulses to appear in the supply rails when the circuit changes-over state (especially when a load is connected to the circuit). These pulses can be picked up by the sensitive amplifier which will cause the circuit to again switch-over states, resulting into motor-boating noise.
Since the circuit operates at 4.5V, it can be easily incorporated in digital circuits. Fig. (b) shows how the circuit can be employed to control the direction of a DC motor. The circuit employs four npn transistors. Transistors T1 and T4 have their bases tied together and they switch-on simultaneously when Q output is logic 1. Similarly T2 and T3 conduct when Q output is logic 1. Thus current through the motor changes direction when the flip-flop toggles. Filters connected in the circuit and tuned to different bands of audio frequencies will enable the same circuit to control more than one device. For instance, a high frequency sound (such as whistle) can switch on device 1 and a low frequency sound (such as clapping) can control device 2.


The circuit described here is that of a metal detector. The opera- tion of the circuit is based on superheterodyning principle which is commonly used in superhet receivers. The circuit utilises two RF oscillators. The frequencies of both oscillators are fixed at 5.5 MHz. The first RF oscillator comprises transistor T1 (BF 494) and a 5.5MHz ceramic filter commonly used in TV sound-IF section. The second oscillator is a Colpitt’s oscillator realised with the help of transistor T3 (BF494) and inductor L1 (whose construction details follow) shunted by trimmer capacitor VC1. These two oscillators’ frequencies (say Fx and Fy) are mixed in the mixer transistor T2 (another BF 494) and the difference or the beat frequency (Fx-Fy) output from collector of transistor T2 is connected to detector stage comprising diodes D1 and D2 (both OA 79). The output is a pulsating DC which is passed through a low-pass filter realised with the help of a 10k resistor R12 and two 15nF capacitors C6 and C10. It is then passed to AF amplifier IC1 (2822M) via volume control VR1 and the output is fed to an 8-ohm/1W speaker. The inductor L1 can be constructed using 15 turns of 25SWG wire on a 10cm (4-inch) diameter air-core former and then cementing it with insulating varnish. For proper operation of the circuit it is critical that frequencies of both the oscillators are the same so as to obtain zero beat in the absence of any metal in the near vicinity of the circuit. The alignment of oscillator 2 (to match oscillator 1 frequency) can be done with the help of trimmer capacitor VC1. When the two frequencies are equal, the beat frequency is zero, i.e. beat frquency=Fx-Fy=0, and thus there is no sound from the loudspeaker. When search coil L1 passes over metal, the metal changes its inductance, thereby changing the second oscillator’s frequency. So now Fx-Fy is not zero and the loudspeaker sounds. Thus one is able to detect presence of metal.


A few designs for remote control switches, using VG40T and VG40R remote control pair, are shown here.
The miniature transmitter module shown in Fig. 1, which just measures 34 mm x 29 mm x 10 mm, can be used to operate all remote control receiver-cum-switch combinations described in this project. A compact 9-volt PP3 battery can be used with the transmitter. It can transmit signals up to 15 metres without any aerial. The operating frequency of the transmitter is 300 MHz. The following circuits, using VG40R remote control receiver module measuring 45 mm x 21 mm x 13 mm, can be used to:
(a) activate a relay momentarily,
(b) activate a relay for a preset period,
(c) switch on and switch off a load.
To activate a relay momentarily (see Fig. 2), the switch on the transmitter unit is pressed, and so a positive voltage is obtained at output pin of VG40R module. This voltage is given to bias the relay driver transistor. The relay gets activated by just pressing push-to-on micro switch on the transmitter unit. The relay remains energised as long as the switch remains pressed. When the switch is released, the relay gets deactivated. Any electrical/electronic load can be connected via N/O contacts of the relay.
To activate a relay for a preset period (refer Fig. 3), the switch on the transmitter unit is pressed momentarily. The transistor gets base bias from VG40R module. As a result the transistor conducts and applies a trigger pulse to IC 555, which is wired as a monostable multivibrator. The relay remains activated till the preset time is over. Time delay can be varied from a few seconds to a few minutes by adjusting timing components.
To switch on and switch off a load (refer Fig. 4), a 555 IC and a decade counter 4017 IC are used. Here the 4017 IC is wired as a flip-flop for toggle action. This is achieved by connecting Q2 output to reset terminal while Q1 output is unused. Q0 output is used for energising the relay. The relay is activated and deactivated by pressing the transmitter switch alternately. So, to activate the load, just press the transmitter switch once, momentarily. The relay will remain activated. To switch off the relay, press the transmitter switch again. This process can be repeated. Time delay of monostable multivibrator is set for about one second.
Note: Short length of shielded wire should be used between VG40R receiver module output and the rest of the circuit. The transmitter with 9V battery must be housed inside a nonmetallic (say, plastic) cabinet for maximum range of operation.



Circuit of a new type of remote control switch is described here. This circuit functions with inaudible (ultrasonic) sound. Sound of frequency up to 20 kHz is audible to human beings. The sound of frequency above 20 kHz is called ultrasonic sound. The circuit described generates (transmits) ultrasonic sound of frequency between 40 and 50 kHz. As with any other remote control system this cirucit too comprises a mini transmitter and a receiver circuit. Transmitter generates ultrasonic sound and the receiver senses ultrasonic sound from the transmitter and switches on a relay. The ultrasonic transmitter uses a 555 based astable multivibrator. It oscillates at a frequency of 40-50 kHz. An ultrasonic transmitter transducer is used here to transmit ultrasonic sound very effectively. The transmitter is powered from a 9-volt PP3 single cell. The ultrasonic receiver circuit uses an ultrasonic receiver transducer to sense ultrasonic signals. It also uses a two-stage amplifier, a rectifier stage, and an operational amplifier in inverting mode. Output of op-amp is connected to a relay through a complimentary relay driver stage. A 9-volt battery eliminator can be used for receiver circuit, if required. When switch S1 of transmitter is pressed, it generates ultrasonic sound. The sound is received by ultrasonic receiver transducer. It converts it to electrical variations of the same frequency. These signals are amplified by transistors T3 and T4. The amplified signals are then rectified and filtered. The filtered DC voltage is given to inverting pin of op-amp IC2. The non- inverting pin of IC2 is connected to a variable DC voltage via preset VR2 which determines the threshold value of ultrasonic signal received by receiver for operation of relay RL1. The inverted output of IC2 is used to bias transistor T5. When transistor T5 conducts, it supplies base bias to transistor T6. When transistor T6 conducts, it actuates the relay. The relay can be used to control any electrical or electronic equipment. Important hints:

1. Frequency of ultrasonic sound generated can be varied from 40 to 50 kHz range by adjusting VR1. Adjust it for maximum performance.

2. Ultrasonic sounds are highly directional. So when you are operating the switch the ultrasonic transmitter transducer of transmitter should be placed towards ultrasonic receiver transducer of receiver circuit for proper functioning.

3. Use a 9-volt PP3 battery for transmitter. The receiver can be powered from a battery eliminator and is always kept in switched on position.

4. For latch facility use a DPDT relay if you want to switch on and switch off the load. A flip-flop can be inserted between IC2 and relay. If you want only an ‘ON-time delay’ use a 555 only at output of IC2. The relay will be energised for the required period determined by the timing components of 555 monostable multivibrator.

5. Ultrasonic waves are emitted by many natural sources. Therefore, sometimes, the circuit might get falsely triggered, espically when a flip-flop is used with the circuit, and there is no remedy for that


Here is a teleremote circuit which enables switching ‘on’ and ‘off’ of appliances through telephone lines. It can be used to switch appliances from any distance, overcoming the limited range of infrared and radio remote controls.

The circuit described here can be used to switch up to nine appliances (corresponding to the digits 1 through 9 of the telephone key-pad). The DTMF signals on telephone instrument are used as control signals. The digit ‘0’ in DTMF mode is used to toggle between the appliance mode and normal telephone operation mode. Thus the telephone can be used to switch on or switch off the appliances also while being used for normal conversation.

The circuit uses IC KT3170 (DTMF-to-BCD converter), 74154 (4-to-16-line demult-iplexer), and five CD4013 (D flip-flop) ICs. The working of the circuit is as follows.

Once a call is established (after hearing ring-back tone), dial ‘0’ in DTMF mode. IC1 decodes this as ‘1010,’ which is further demultiplexed by IC2 as output O10 (at pin 11) of IC2 (74154). The active low output of IC2, after inversion by an inverter gate of IC3 (CD4049), becomes logic 1. This is used to toggle flip-flop-1 (F/F-1) and relay RL1 is energised. Relay RL1 has two changeover contacts, RL1(a) and RL1(b). The energised RL1(a) contacts provide a 220-ohm loop across the telephone line while RL1(b) contacts inject a 10kHz tone on the line, which indicates to the caller that appliance mode has been selected. The 220-ohm loop on telephone line disconnects the ringer from the telephone line in the exchange. The line is now connected for appliance mode of operation.

If digit ‘0’ is not dialed (in DTMF) after establishing the call, the ring continues and the telephone can be used for normal conversation. After selection of the appliance mode of operation, if digit ‘1’ is dialed, it is decoded by IC1 and its output is ‘0001’. This BCD code is then demultiplexed by 4-to-16-line demultiplexer IC2 whose corresponding output, after inversion by a CD4049 inverter gate, goes to logic 1 state. This pulse toggles the corresponding flip-flop to alternate state. The flip-flop output is used to drive a relay (RL2) which can switch on or switch off the appliance connected through its contacts. By dialing other digits in a similar way, other appliances can also be switched ‘on’ or ‘off.’

Once the switching operation is over, the 220-ohm loop resistance and 10kHz tone needs to be removed from the telephone line. To achieve this, digit ‘0’ (in DTMF mode) is dialed again to toggle flip-flop-1 to de-energise relay RL1, which terminates the loop on line and the 10kHz tone is also disconnected. The telephone line is thus again set free to receive normal calls.This circuit is to be connected in parallel to the telephone instrument



Power amplifier delivers 600 watts into 8 ohms (bridge mono) or 300 watts into 4 ohms (stereo) -
ideal for clubs, churches, auditoriums and more.
Admission to the 600W bipolar amps is achieved via XLR or phone jack, and output is achieved through two Speakon-type connectors or terminals.the 600W bipolar has over 860 ground switches, user switchable clip limiters,
selectable high-pass filter, and the ability to distinguish between stereo, parallel and bridge modes to choose, so that the the 600W bipolar series amplifiers ideal for real applications.

Power Output: 300W @ 4 ohms stereo, 200W stereo @ 8 ohms
High-current toroidal transformers for greater power and low noise
Independent user-defeatable peak limiters reduce distortion
Selectable high pass filter at 30Hz or 50Hz
XLR and 1 / 4 “TRS input jacks
Binding Post and Speakon outputs?-Type
Front-mounted gain control for easy access
Signal and Peak LED indicators to monitor performance
Short circuit, thermal, subsonic, RF protection, output DC offset
Power on / off muting

Rangkaian Transmitter FM 15 W

15W Fm-transmitter

Building a good fm-transmitter(88-110Mhz) begins with getting a good schematic. You don't have to understand the precise working of the transmitter to build it. But some basic information won't harm. A transmitter alone is, as you probably know, is not enough to start your radio-station. In the simplest form you need 4 things. First an input device such as an amplifiler you also use with your home-stereo.
You can also use a walkman. Details about input-devices in the page: "Input". Second you need a regulated power-supply. In this case a 14-18 Volts/2,5-3,5 Ampere. One of the most influencial things you need is antenna and coax-cable. More about this later on. And finally the transmitter itself. You can devide the transmitter in two main parts: the oscillator and the amplifier. The oscilator converts electric sound information into electromagnetic waves. The amplifier gives these waves
a bigger amplitude.

For More Info Please Visit Here
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LM1036 Stereo Tone Control circuit diagram

This is a stereo audio tone control circuit which build based on IC LM1036. This circuit will controll bass/treble level tone, volume and balance between right channel and left channel (input 1 and 2 ). You may use this circuit for stereo applications such as car radio, TV and audio systems, mp3 player, dvd player, ipod and more. An additional control input allows loudness compensation to be simply effected. The circuit should be works with supply voltage 9V to 15V DC.

Tone control features:

* Wide supply voltage range, 9V to 16V
* Large volume control range, 75 dB typical
* Tone control, ±15 dB typical
* Channel separation, 75 dB typical
* Low distortion, 0.06% typical for an input level of 0.3 Vrms
* High signal to noise, 80 dB typical for an input level of 0.3 Vrms
Read MoreLM1036 Stereo Tone Control circuit diagram


Active Radio Antenna circuit diagram
Active Radio Antenna circuit diagram

On the shortwave band this active antenna is comparable to a 20 to 30 foot wire antenna. This circuit is designed to be used on receivers that use untuned wire antennas, such as inexpensive units and car radios.

L1 can be selected for the application. A 470uH coil works on lower frequencies ( AM ). For shortwave, try a 20uH coil. The unit can be powered by a 9 volt battery. If a power supply is used, bypass the power supply with a .04uF capacitor to prevent noise pickup. The antenna used on this circuit is a standard 18″ telescoping type. Output is taken from jack J1 and run to the input on the receiver.


FM Wireless Microphone circuit diagram

The range of frequencies for the FM broadcast band is 90MHz (MHz = Megahertz or 90 million cycles per second). Because the FM microphone has a variable tuned circuit, it can be tuned to a quiet spot on your local FM broadcast band for the best reception. When the small microphone element is struck by sound, it converts the audio to a change in current through resistor R1 (see schematic diagram).

This electrical change is amplified and eventually frequency modulates the transmitter. The transmission range of the FM microphone is approximately 100 feet, depending on the efficiency of the antenna (properly tuned or not) and the quality of the FM radio receiver.

Car Adapter Circuit with ECG184

car converter 12 VDC to 9 VDC converters

for audio ,playstation,DVD,tv etc., is that we have designed for 12DC to 9DC converters that we bring to our design circuit . They are all effective in Switch Mode Power Supplies regulated output. We have developed a series of DC-DC power supply models ranging from 1 watt to 500 watts, which we incorporated into the new controller of DC converters. We are also developing new areas whenever necessary to meet customer requirements. We can provide some custom products that changes on the following products and fully custom DC-DC, new products, such as DC Battery Backup Power Supplies.
Read MoreCar Adapter Circuit with ECG184

Skema Rangkaian Sensor Color Circuit Diagram

This is the color sensor circuit diagram. This circuit will sense eight colors that are: , green, red and blue (as primary colours); magenta, cyan and yellow (as secondary colours); and black and white. It’s will be very useful for robotics project.

The circuit is based on the fundamentals of optics and digital electronics. The object whose colour is required to be detected should be placed in front of the system. The light rays reflected from the object will fall on the three convex lenses which are fixed in front of the three LDRs. The convex lenses are used to converge light rays. This helps to increase the sensitivity of LDRs. Blue, green and red glass plates (filters) are fixed in front of LDR1, LDR2 and LDR3 respectively. When reflected light rays from the object fall on the gadget, the coloured filter glass plates determine which of the LDRs would get triggered.

The circuit makes use of only ‘AND’ gates and ‘NOT’ gates. When a primary coloured light ray falls on the system, the glass plate corresponding to that primary colour will allow that specific light to pass through. But the other two glass plates will not allow any light to pass through. Thus only one LDR will get triggered and the gate output corresponding to that LDR will become logic 1 to indicate which colour it is. Similarly, when a secondary coloured light ray falls on the system, the two primary glass plates corres- ponding to the mixed colour will allow that light to pass through while the remaining one will not allow any light ray to pass through it. As a result two of the LDRs get triggered and the gate output corresponding to these will become logic 1 and indicate which colour it is.

Source of this color sensor circuit:
Visit the page for complete explanation.
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Automatic Railway Gate Control & Track Switching

Present project is designed using 8051 microcontroller to avoid railway accidents happening at unattended railway gates, if implemented in spirit. This project utilizes two powerful IR transmitters and two receivers; one pair of transmitter and receiver is fixed at up side (from where the train comes) at a level higher than a human being in exact alignment and similarly the other pair is fixed at down side of the train direction. Sensor activation time is so adjusted by calculating the time taken at a certain speed to cross at least one compartment of standard minimum size of the Indian railway. We have considered 5 seconds for this project. Sensors are fixed at 1km on both sides of the gate. We call the sensor along the train direction as ‘foreside sensor’ and the other as ‘aft side sensor’. When foreside receiver gets activated, the gate motor is turned on in one direction and the gate is closed and stays closed until the train crosses the gate and reaches aft side sensors. When aft side receiver gets activated motor turns in opposite direction and gate opens and motor stops. Buzzer will immediately sound at the fore side receiver activation and gate will close after 5 seconds, so giving time to drivers to clear gate area in order to avoid trapping between the gates and stop sound after the train has crossed.

The same principle is applied for track switching. Considering a situation wherein an express train and a local train are traveling in opposite directions on the same track; the express train is allowed to travel on the same track and the local train has to switch on to the other track. Two sensors are placed at the either sides of the junction where the track switches. If there’s a train approaching from the other side, then another sensor placed along that direction gets activated and will send an interrupt to the controller. The interrupt service routine switches the track. Indicator lights have been provided to avoid collisions. Here the switching operation is performed using a stepper motor. Assuming that within a certain delay, the train has passed the track is switched back to its original position, allowing the first train to pass without any interruption. This concept of track switching can be applied at 1km distance from the stations.

The project is simple to implement and subject to further improvement.

Model of Automatic Railway Gate Control & Track Switching

Model of Automatic Railway Gate Control & Track Switching

Gate Control

Railways being the cheapest mode of transportation are preferred over all the other means .When we go through the daily newspapers we come across many railway accidents occurring at unmanned railway crossings. This is mainly due to the carelessness in manual operations or lack of workers. We, in this project has come up with a solution for the same. Using simple electronic components we have tried to automate the control of railway gates. As a train approaches the railway crossing from either side, the sensors placed at a certain distance from the gate detects the approaching train and accordingly controls the operation of the gate. Also an indicator light has been provided to alert the motorists about the approaching train.

Railway crossing

Gate control

Track Switching

Using the same principle as that for gate control, we have developed a concept of automatic track switching. Considering a situation wherein an express train and a local train are travelling in opposite directions on the same track; the express train is allowed to travel on the same track and the local train has to switch on to the other track. Indicator lights have been provided to avoid collisions .Here the switching operation is performed using a stepper motor. In practical purposes this can be achieved using electromagnets.

Track Switching

Track Switching

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