DC converter circuit

This dc converter raise a dc voltage at almost a double value and is useful for raising the output voltage of solar batteries up to the required level for charging acid or NiCad batteries. It can deliver up to 3Amps. The measurement values with 2A load are shown in the bottom table.
In this article we assume that the input voltage is 12V and the output is 22V. IC1a, R2 and C5 build a square wave generator. This signal is available in reversed form at IC1d output.
Read the rest of thid dc to dc converter circuit…


  RE200B CBB61 C2383 CM108 ADF4360 A1941 74LVC4245A FSDL0165RN MCZ33099CEG VRE202C LM2576T CD4011BE LM555CM UA741

SC-11S1 Marantz Preamplifier

The SC-11S1 Marantz preamplifier is a middle class separate amplifier which came back after an interval of a quarter of a century! These unique models are most aggressive products which we adopted the latest philosophy, technic and technology.

SC-11S1 Marantz features

• High Channel Separation and Ultra Wide Frequency Response Design
• Evolved HDMI? SA3 Module
• Constant Current Feedback Phono Equalizer
• Balanced Linear Control Volume by Wolfson WM8816
• Subsonic Filter
• Bi-Amp Mode
• Low Impedance Input Buffer Amplifier
• Balanced Input Type Headphone Amplifier
• Choke Input System Power Supply Circuit
• Toroidal Transformer with Aluminum Shield Case
• Trim Adjustment and Electric Tone Control
• Marantz F.C.B.S. (Floating Control Bus System) for Multiple link
• Remote Power Control (Trigger)

Marantz SC-11S1 specifications

IN/OUTPUTS
AUDIO

• Main In/Pre Out - / Balanced: 1, Unbalanced: 1
• Bridge Mono Mode/Bi-Amp Mode - / X (as a monaural control amplifier)
• Headphone Out 1 (A balanced input current feedback headphone amplifier)
• Phono Input: MM/MC (Constant Current Feedback Phono EQ Circuit)
• Analog L&R In: Balanced: 2, Unbalanced: 5
• Analog L&R Out: Balanced: 0, Unbalanced: 2

OTHER

• External control Trigger Out for SM-11S1: 2, F.C.B.S. In/Out: 1/1
• D-Bus Remote (RC-5) In/Out: 0/0
• AC Outlets (Switched/Unswitched): 0/0

Specifications

• THD Balanced: 0.002%, Unbalanced: 0.003%
• Input Sensitivity/Impeance PHONO MC: 280μV/100 ohms, MM: 2.9mV/47k ohms, Balanced/Unbalanced: 250mV/20k ohms
• Frequency Response Balanced/Unbalanced: 5Hz – 120kHz ( /- 3dB)
• S/N Ratio PHONO MC: 78dB (0.5mV input), MM: 89dB (5mV input), Balanced: 98dB (500mV input), Unbalanced: 99dB (500mV input)
• Number of Channels 2
• HDAM HDAM-SA3
• Power Transformer Large Capacity Toroidal w/Shielded Case
• Current Feedback Amplifier Current Feedback Amplifier Stage
• Tone Control Bass (50Hz): /- 8dB, Treble (20kHz): /- 8dB
• Source Direct - (Tone Off equal Source Direct.)

General

• Color: Gold
• Front Panel: 3pces Aluminum
• Remote Control: Aluminum Top Marantz System Remote Controller
• Power Requirement: AC 120V 60Hz
• Power Consumption: 35W (UL60065)
• Dimensions W x H x D (Inchs): 17-5/16″ x 5″ x 17″
• Weight (lbs): 35.3

SC-11S1 Marantz photos

Guitar amplifier circuit with LM391

This is a medium power guitar amplifier is recommended especially for portable amplifier. The amplifier is a combination between a simple integrated audio driver, LM391-80 and a stage of output power designed contratemps with bipolar transistors.
Thermistor NTC, which is in temperature contact with output power transistors, allows to separate AO LM391 power stage when it heats too much.
Read the rest of this guitar amplifier circuit…

Quality FM transmitter circuit

This house FM transmitter for your stereo or any other amplifier provides a good signal strength up to a distance of 500 meters with a power output of about 200 mW. It works off a 9V battery.

The audio-frequency modulation stage is built around transistor BF494 (T1), which is wired as a VHF oscillator and modulates the audio signal present at the base. Using preset VR1, you can adjust the audio signal level.

Audio FM transmitter circuit diagram

The VHF frequency is decided by coil L1 and variable capacitor VC1. Reduce the value of VR2 to have a greater power output.
The next stage is built around transistor BC548 (T2), which serves as a Class-A power amplifier. This stage is inductively coupled to the audio-frequency modulation stage. The antenna matching network consists of variable capacitor VC2 and capacitor C9. Adjust VC2 for the maximum transmission of power or signal strength at the receiver.

If you design a good pcb layout you can use it as a car fm transmitter.
For frequency stability, use a regulated DC power supply and house the transmitter inside a metallic cabinet. For higher antenna gain, use a telescopic antenna in place of the simple wire. Coils L1 and L2 are to be wound over the same air core such that windings for coil L2 start from the end point for coil L1. Coil winding
details are given below:
L1: 5 turns of 24 SWG wire closely wound over a 5mm dia. air core
L2: 2 turns of 24 SWG wire closely wound over the 5mm dia. air core
L3: 7 turns of 24 SWG wire closely wound over a 4mm dia. air core
L4: 5 turns of 28 SWG wire on an intermediate-frequency transmitter (IFT) ferrite core
Check the related posts for somestereo fm transmittercircuits.

Touch volume control circuit

Touch controls are not only used to switch devices on or off. They can also be used to control different functions. One good example is the TV remote control. If it is very important to keep the activated functions for a long period of time, it is always better to use a digital memory system. However, if small drifts in the control status is acceptable, a simple analog design can be used to memorize the status.

The touch volume controller is one such analog memory touch control switch. The main function centers mostly on the IC1. It is an opamp configured as an integrator with a high impedance input. If sensor 1 is touched, the capacitor C2 charges through the skin resistance and voltage at the output of IC1 decreases linearly until it reaches zero volt.

Touching the other sensor (sensor 2) will produce the opposite result: the voltage at the pin 6 of IC1 will increase linearly until it reaches the power supply level. The special function of this touch volume control circuit is that after moving your finger away from the sensor(s), the output voltage of IC1 stays at that level.

This voltage value is memorized by C2. This analog memory however has a problem in long time periods: The voltage value drifts away by 2 % per hour due to the unavoidable current leak in the capacitor. To improve this situation, it is highly recommended to put this circuit in a moisture proof box.

This touch volume controller circuit has a wide application range. It can be used in devices where a potentiometer can be controlled through voltage levels. The touch sensors can alse be replaced with conventional push button switches. The capactiors C1 and C4 are very important in the circuit: they prevent the IC1 from oscillating. Simultaneously closing both switches will not damage the circuit.

Touch volume control circuit diagram

Touch volume control PCB layout

IC CA3130 datasheet

bt169 Circuit ft232R Circuit s3c2440 Circuit S9012 Circuit sr260 Circuit 1n5401 Circuit ua741cn Circuit bta41 Circuit

88 108 MHz 40W wideband power amplifier MRF171A

One wideband fm power amplifierdesigned with MRF 171A MosFet transistor. The output rf power is somewhere around 40W , the gains is 20dB ( 100 X ) . The input rf power is 400mW.

Wideband UHF Amplifier

This UHF wideband amplifier(Ultra High Frequency amplifier) has a total gain of 10 to 15 dB in the 400 – 850 MHz domain frequency so it can be used where the tv signal is weak.

For this UHF antenna tv amplifier to work correctly you need to cut the components pins as short as possible. C1, C2, C6, C7 are SMD type ( surface mounted ). This antenna tv amplifier or uhf wideband amplifier need to be build inside of a metal box and then connected close to thetv antenna.

The power supply is a simple 12V stabilized source. The antenna tv amplifier can be connected directly to the power supply thru coaxial cable of the tv antenna but you need a 10 – 100uH coil on the alimentation line. The tv set will be connected to the uhf amplifier thru a small coupling capacitor.
Adjusting is easy, just bring the P1 to the middle and then adjust it untill you obtain the best tv image quality.

Antenna TV amplifier circuit schematic

For moretv antenna amplifierscheck the list bellow.
Tv antenna UHF amplifier components:
L1 = L2 = 2 turns, 3mm ?
L3 = L4 = 10uH or 10 turns, 0.2mm ? on ferrite
T = 2SC3358

UUS 65

A basic UUS 65 73 MHz fm transmitter circuit schematic which can be used as UUS oscillator with no explanation …
65 – 73 MHz transmitter ( oscillator ) circuit components:

L1 = 8 t / 0.3mm / 6mm
L2 = 8-12 t / 1mm / 15mm / 1mm gap
SRF = 60t / 0.2mm / 3mm / ferrite

65-73 MHz transmitter circuit schematic

Source:http://www.hqew.net/circuit-diagram/UUS-65-_8702.html

Power Amplifier VMOS OTL 10 Watt

circuit VMOS 10 Watt Amplifier
Hello! This the circuit amplifies small-sized.it uses the equipment VMOS , number BD512 and BD522. which be pillar heart of the circuit. By it very the circuit is the character of OTL , make build easy and the price economizes. It is giving watt about 10W when , use force against 8ohm size loudspeakers and use a place turn on the power 33V sizes that the trend about 1.5A yes.

Source: http://www.hqew.net/circuit-diagram/Power-Amplifier-VMOS-OTL-10-Watt_8661.html

Power Amplifier OCL 40W by 2N3055 MJ2955

The 40W Amp OCL 2N3055 MJ2955 is easy to build,and very inexpensive. To use Power Supply 35V -35V 2A. Transistor 2N3055 MJ2955 must be mounted on heatsink. Can be directly connected to CD players, tuners and tape recorders.

This circuit is one that stands out for ages over 40 years, with sound quality that is hard to find compared be other circuits. If you experimental build or ask people who try already built. Will believe that this is not as exaggerated statement more than true.

This power amplifier series circuit, be able to output of up to 40 watt on load 8 ohm, and will provide output capacity of up to 60 watt load 4 ohm.
The circuit design an All complementary all direct coupling (except the input), Making low frequency response of the circuit well.

Circuit 40W Amp OCL 2N3055 MJ2955

The transistor(MPS9632) Q1, Q2 together to as a differential amplifier, By has R10,R4 and C2 together constitute the feed back circuit and defined an all gain ratio of circuit. At emitter circuit has zener diode is connected as maintain a constant voltage 15V.

The transistor Q5 is the part second amplifier circuit, by has C3 is to feedback between pin base and collector, for prevent procreation oscillator way high frequency

Q8,Q9 acting as the driver circuit to drives the power transistor Q10(MJ2955),Q11(2N3055).
For Q6, Q7 acts as the output transistor protection circuit from damage. Because the current flowing through the load too much such as a speaker cable short-circuited, by will acts as short the bias circuit of the output transistor is reduced so that it not works.

Q3 serves limit current, the general bootstrapped circuit that use the RC. for Q4 acts as setting bias level of the output transistor which which be instead Diodes same the normal amplifier circuit. This connection reduces the crossover distortion as well.
VR1 serves as to adjust a bias voltage the idle current to the circuit.

Parts
Q1,Q2,Q3_________MPS9632___Transistors, Bipolar, Si NPN Low-Power Audio Frequency Small Signal Transistors or
Replace Part is BC167, BC171, BC182, BC237, BC547

Q3,Q6,Q9_________MPSA06____NPN general purpose transistor ____
Replace Part : BC 639, 2SD667, 2SD1226, 2SD1616A

Q5,Q7,Q8_________MPSA56____Small Signal General Purpose PNP___
Replace Part : BC 640, 2SB647, 2SB910, 2SB1116A
Q10______________MJ2955
Q9_______________2N3055
ZD1______________15V 0.5W___zener diode
D1,D2_____________1N4148____75V 150mA Diodes
R1,R10,R13,R14_____10K____1/4W Resistor
R2________________7.5K___ 1/4W Resistor
R3________________3.3K___ 1/4W Resistor
R4________________470 OHM__ 1/4W Resistor
R5________________27K_____ 1/4W Resistor
R6,R8_____________1.2K_____ 1/4W Resistor
R7________________150 OHM___ 1/4W Resistor
R9________________680 ohm___ 1/4W Resistor
R11,R12___________100 ohm ___ 1/4W Resistor
R15,R16___________220 ohm ___ 1/4W Resistor
R17,R18___________0.5 ohm ___ 2W Resistor
R19_______________10 ohm ____ 1W Resistor
VR1_______________1K Potentiometer
C1________________10uF 16V___ Electrolytic Capacitors
C2________________47uF 16V___ Electrolytic Capacitors
C3________________680pF 50V_____ Polyester Capacitor
C4________________0.1uF 63V_____ Polyester Capacitor
C5,C6_____________47uF 50V_____ Electrolytic Capacitors
L1 use #24 copper wire on air coil 5mm.

2SA1248=2SA1249=SAB649
2SC3116=2SC3116=2SC3117=2SD669

PCB 40W Amp OCL 2N3055 MJ2955

Customization this circuit.
When this project is done, not to the speaker cable, adjust VR1 at the center. And then power supply to the circuit, to measure at output point as the loud speaker with the ground Should be less than 0V or 0.1V.

Then uses the voltmeter to measure the voltage across R17, as with adjust the VR1 slowly until you read 0.01V Or may be adjusted by measuring the Idle current is about 15-30mA.
And then, connect the speakers, and input single to use work immediately.
More parts information:

PIC16C711 DM9161 STA540 BA4560 74HC393 HA17555 IRF5210 74HC595N 1N5402 PIC16F72 ATMEGA328P-PU SG3524 LM2676 74HCT04

Power Amplifier Guitar Practice

Circuit Guitar Practice Amplifier
This is Guitar Practice Amplifier Circuit. Friends who like to play electricity guitar may like this circuit. Because it has can to amplify electricity guitar by it has circuit tiny size. Use the integrated circuit LM389 perform amplify loudly increasingly. And The VR1-5K perform fine decorate the popularity in the sound. For a loudspeaker should choose that is valuable impedance about 8-32 ohm. From your circuit will think we use low voltage supply and the a little equipment. Then make the sound that go out to not loud many loudspeaker. Make friends someone may can be defeated sir.

 Related links:

LM723 LPC2138 DS2408 BUF634 IRF9640 C8051F120 FT245BM TDA8359J

Opto-Tone (Control sound by light)

circuit Opto-Tone (Control sound by light),With IC 555 and sensitive light by LDR.

UHF indicator

UHF indicator or wavemeter is some kind of device that measures frequencies and determines LC circuit frequecy resonance . This device does not need to radiate.
The oscillator is build with T1 and T2 (2 x BF494) and can be adjusted with C1 and Lx. The Lx coil is connected outsite of the metal box and has to be changeble handiest.
If Lx is inductively coupled with another LC coil wich has the same frequency as the wavemeter, then will extract energy from oscillator coil, this will result in a voltage reduction.
With Lx = 2 turns 1mm (SWG19) over 15mm, the ultra high frequency indicator – wavemeter frequency cover is 50 … 150 MHz.
BF494 transition frequency is 150Mhz, if you want tomeasure higher frequencieschange it with BFR 91 wich has an Ft of 250MHz.
If you want to use thisuhf indicatoras anabsobtion wavemeterorrf field measurementunplug from the battery, in this case you have to look for a minimum value on the multimeter.

Wavemeter circuit wiring diagram

VHF AM converter circuit

There are many people who want to listen whats going on in VHF 108 – 132 MHz. This vhf am converter converts a band between 106 and 150 MHz, so you can listen even 2m radio amateurs (144Mhz).
Thisvhf am converteris build with anvhf amplifier, one mixer and oscillator. After the input signal is amplified with T1 it is applied to a mosfet mixer and combined with the quartz oscillator output.
The tuning is between 6 and 30 MHz. Thequartz frequencyis fx = fi-fo where fo is output frequency and fi is input frequency.

VHF-AM converter circuit diagram

Components:
L1 = 7 turns / 3 turn from ground
L2 = L3 = 3 turns
L4 = 4 turns / 1 turn from ground
L1 … L4 = CuEm SWG 20
L6a = 4 tunrs / SVG 36
L6b = 4 turns / SWG 24
L6a and L6b are build togheter on ferrite 3 x 6 mm
L5 = L7 = 0.82 uH
L8 = 1 uH
Quartz crystal = 100 …. 120 MHz overtone armonic 5

VHF-AM converter pcb layout

Reprinted the url of this article at http://www.hqew.net/circuit-diagram/VHF-AM-converter-circuit_8635.html

Dynamic mic preamplifier circuit

This mic preamp uses the low noise IC uA739. The circuit is an example of how a good preamplifier can be designed for dynamic microphones. The IC houses two identical integrated preamp circuits. The second preamp is used in identical manner for the second channel of the stereo microphone.

Diagram bellow shows the pin numbers (in brackers) for the second identical channel. All external parts are identical to those shown in the schematic.

The non-inverting input is biased at about 50% of the power supply. This bias voltage is set by the voltage divider circuit R1 and R4. The point between R1 and R4 is used commonly for both channels.
The unwanted HF signals coming from the microphone are filtered out by the RC-circuit composed of R3/C4. Frequency compensation is done by the R7/C6 circuit. The values of R7 and C6 were designed to avoid oscillation at the amplification level of 100.

The input impedance is about 47K. This means that a normal dynamic microphone gets connected to a high impedance preamp which in turn produces good results. The output impedance is about several hundred ohms.

THe maximum peak-peak output voltage is about several volts lower than the supplied power. The frequency range is from 20Hz to 20KHz (-3dB). The upper cutoff frequency is 80KHz when the low-pass filter is removed from the circuit. The IC shown can be replaced with TBA231 or SN76131 without changind the external circuit.

Dynamic microphone preamp circuit diagram

measurements temperature by diode 1N4148

measurements temperature by diode 1N4148

temperature by diode 1N4148 and IC741.
easy to make and use.
Out to Voltmeter.
*** Low cost too !

When I wants the circuit takes the temperature to are simple. I uses Diode 1N4148 be formed check the temperature. By when feed voltage change it. It is have current flow be stable. When the temperature that Diode, change make Voltage. At it modifies with VR1 and VR2 fine decorate for show that is correct most fining decorates. The important I uses the temperature certainly compare with accurate temple. By compare with reserve 0 the degree Celsius per 0 Volt. For the certainty advises that, should use Digital Voltage Meter. Show well almost forget the important point should. Give power supply Regulator high-quality , such as IC 7815 and IC 7915 etc. Try usable this circuit sees, regard good base of the circuit takes the temperature sir.

xc3s200 isl6251 pic12c508a tca965 hs1101 lm7815 rtl8201bl

Single Supply 16-Bit ADC Driver

This circuit shows the LT6203 driving an LTC1864 unipolar 16-bit, 250ksps A/D converter. The bottom half of the LT6203 is in a gain of 1 and buffers the 0V negative fullscale signal VLOW into the negative input of the LTC1864. The upper half of the LT6203 is in a gain of 10, referenced to the buffered voltage VLOW and drives the positive input of the LTC1864. The input range of the LTC1864 is 0V to 5V so for best results the input range of VIN is from VLOW, about 0.4V to about 0.82V. Figure 4 shows an FFT obtained with a 10.1318kHz (coherent) input waveform, with no windowing or averaging. Spurious free dynamic range is seen to be 100dB.

74hc4066 Circuit pic16f630 Circuit hmc5883l Circuit pic16f873 Circuit MFRC522 Circuit 74HC4040 Circuit 2N5088 Circuit SFH6156 Circuit

Simple Photovoltaic Charger

The LTC4071 allows simple charging of Li-Ion/Polymer batteries from very low current, intermittent or continuous charging sources. A near-zero current low battery latching disconnect function protects even the lowest capacity batteries from deep discharge and potentially irreparable damage. The 550nA to 50mA operating current makes charging possible from previously unusable sources. With its low operating current the LTC4071 is well suited to charge low capacity Li-Ion or thin film batteries in energy harvesting applications. The unique architecture of the LTC4071 allows for an extremely simple battery charger solution, requiring just one external resistor.

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Reference Divider with Op Amp Input Bias Current Balancing

The LT5400 is a quad resistor network with excellent matching specifications over the entire temperature range. All four resistors can be accessed and biased independently, making the LT5400 a convenient and versatile choice for any application that can benefit from matched resistors. These resistor networks provide precise ratiometric stability required in highly accurate difference amplifiers, voltage references and bridge circuits.

lm1875t AT24c512 tda8177 bt138 stk4152II l293b cd40106B 2n3819

Relative Humidity Sensor Digitizer-Charge Pump Based

Hygrometer Digitizer Has 0.3% Accuracy, Although Sensor Must Float Off-Ground. Humidity Sensor Determines Charge Delivered to A1 Integrator During Each Charge Pump Cycle. Resultant A1 Output Ramp Is Reset by Level Triggered C1 via Q1. Output Frequency, Taken at C1, Varies with Humidity

Remote CPU/ASIC/FPGA Temperature Sensor

The LTC2997 is a high-accuracy analog output temperature sensor. It converts the temperature of an external sensor or its own temperature to an analog voltage output. A built-in algorithm eliminates errors due to series resistance between the LTC2997 and the sensor diode.

Source: http://www.hqew.net/circuit-diagram/Remote-CPU$2fASIC$2fFPGA-Temperature-Sensor_8026.html

RGB Video Inverter

This circuit is useful for viewing photographic negatives on video. A single channel can be used for composite or monochrome video. The inverting amplifier stages are only switched in during active video so the blanking, sync and color burst (if present) are not disturbed. To prevent video from swinging negative, a voltage offset equal to the peak video signal is added to the inverted signal.

Low Noise Low Ripple Triple Output Supply Providing 1V, 8A and 1.8V, 5A and 1.5V, 3A

The LT3070 is a low voltage, UltraFast transient response linear regulator. The device supplies up to 5A of output current with a typical dropout voltage of 85mV. A 0.01μF reference bypass capacitor decreases output voltage noise to 25μVRMS. The LT3070’s high bandwidth permits the use of low ESR ceramic capacitors, saving bulk capacitance and cost. The LT3070’s features make it ideal for high performance FPGAs, microprocessors or sensitive communication supply applications.

tda8177 bt138 stk4152II l293b cd40106B 2n3819