TREE

The circuit was designed to create a spare and reserve power source with the use of batteries during the absence of power from the mains. BD139 – NPN power transistor used for driver stages in hi-fi amplifiers and television circuits because of its low voltage at 80 V maximum and high current at 1.5 A maximum. Bridge Rectifier – also known as bridge rectifier which has four diodes arranged in a bridge configuration where the output voltage has the same polarity with either polarity of the input voltage.     1N4002 – a 1.0 Amp Silicon rectifier with voltage range of 50 to 1000 Volts and possessing features such as guaranteed high temperature soldering, high current capability, diffused junction, low reverse leakage, utilizes void-free molded plastic technique for low cost construction, and carries Underwriters Laboratory Flammability Classification of 94V-0 by its plastic package. One of the main components in the construction of this circuit is the transformer which ...

This is a simple Project of 12 V AC Dimmer Circuit Diagram. 12-V AC Dimmer Circuit Diagram The circuit described here is derived from a conventional design for a simple lamp dimmer, as you can see if you imagine a diac connected between points A and B. The difference between this circuit and a normal diac circuit is that a diac circuit won’t work at 12 V. This is the fault of the diac. Most diacs have a trigger voltage in the range of 30 to 40V, so they can’t work at 12 V, which means the dimmer also can’t work. 12-V AC Dimmer Circuit Diagram The portion of the circuit between points A and B acts like a diac with a trigger voltage of approximately 5.5 V. The network formed by R1, P1 and C1 generates a phase shift relative to the supply voltage. The ‘diac equivalent’ circuit outputs a phase-shifted trigger pulse to the triac on each positive and negative half-cycle of the sinusoidal AC voltage. This works as follows. First consider the positive half of the sine wave. C1 charges when the...

Here is an ultra-sensitive LPG sensor that generates loud beeps when it senses any gas leakage. It detects vapours of liquefied petroleum gas anywhere between 200 and 10,000 ppm and drives a piezobuzzer to catch attention for immediate action. The buzzer beeps until the concentration of gas in the air decreases to a safe level. The circuit uses an MQ6 gas sensor, which is designed to sense LPG, propane and isobutane gases. Circuit and working Fig. 1 shows the circuit of the LPG sensor. The circuit is built around 5V voltage regulator 7805 (IC1), gas sensor MQ6 (GS1), counter IC 4060 (IC2) and a few discrete components. GS1 is a six-pin gas sensor that can detect very small traces of LPG in the air and has a swift response time. However, it has very less sensitivity to alcohol and smoke. The sensor’s output is in the form of resistance. Fig. 1: Circuit of the sensitive LPG sensor As indicated in Fig. 1, the pins of GSI are H, A and B, two each on either side. H pins are for the heater w...

Back in this post (http://diystrat.blogspot.com/2011/11/hofner-colorama-ii-restoration-project_30.html), we applied some initial coats of paint (two complete rattle cans, in fact) to our vintage Hofner Colorama II and left it to dry for a few weeks. This is how it looked after that: The whole body was then wet sanded with 400 grit paper wrapped around a rubber sanding block. This left us with a clear view of any imperfections that were either small divots that were missed at the time of filling, or where the filler didn’t stay in place during pre-paint-application sanding. Rather than applying hundreds of coats of paint until these were filled in, they were spot-filled instead. To do this, we sprayed some of the red paint from the same rattle can into the rattle can lid, left it to thicken up for 10 minutes or so, and then applied it with a small paint brush (the paint brush can be cleaned afterwards with mineral spirits (turps) and live to see another day). The filled-in areas were th...

This is a Simple Project of Remote Control Receiver Circuit Diagram. An infrared receiver, or IR receiver, is hardware that sends information from an infrared remote control to another device by receiving and decoding signals.This circuit is based on the Sharp GP1U52X IR module and 1NS8048L microprocessor. The GP1U52X is a hybrid IC/infrared detector that provides a strong clean signal for later filtering and demodulation. Remote Control Receiver Circuit Diagram

How to make a Simple Automatic Street Lights Intensity Control. White LED (Light Emitting Diodes) substitutes HID lanterns in road illumination system to add on dim element. 8051 family’s micro-controller is bring into play to control the power by growing pulse width transformed pointers that impels a MOSFET to swap the Light Emitting Diodes accordingly to accomplish most wanted function. Automatic Street Lights Intensity Control Circuit Diagram In the current system, maximum lightning over the freeways is completed through HID (High Intensity Discharge lamps), the energy utilization of HID lamps/lanterns are high. The intensity of HID lamps cannot be controlled, in harmony to the necessity, therefore there is a requirement to swap to a substitute way of illumination system i.e., by making use of LEDs. This lighting system is constructed to conquer the disadvantages of High Intensity Discharge lamps. This lightning system exhibits the utilization of the Light emitting diodes or LED’s a...

This is a simple Project of Nicad Battery Protection Circuit Diagram. If a NiCad battery is discharged to a point at which the lowest capacity cell becomes fully discharged and reverses polarity, that cell will usually short internally and become unusable.  To prevent this type of damage, this circuit detects a one-cell drop of 1.25 V and turns the load off before cell reversal can occur. Low-current zener or other voltage sensor Dl and resistors Rl and R2 establish a reference level for transistor Ql. These resistors bias the zener to a few microamperes above its `knee.` Therefore, if battery voltage falls more than 1.25 V, Ql turns off, turning off Q2, and disconnecting the load.   Nicad Battery Protection Circuit Diagram After the load is disconnected, if the battery returns to nominal voltage, the high value of resistor shunting Q2 provides enough output voltage to reset the voltage sensor and turn Q2 back on. If desirable, shunt diode D2 or the parasitic diode of the...

20 years ago it was common to see small key-holders emitting an intermittent beep for a couple of seconds after its owner whistled. These devices contained a special purpose IC and therefore were not suited to home construction. The present circuit is designed around a general purpose hex-inverter CMos IC and, using miniature components and button clock-type batteries can be enclosed in a matchbox. It is primarily a gadget, but everyone will be able to find suitable applications. Circuit operation: This device beeps intermittently for about two seconds when a person in a range of around 10 meters emits a whistle. The first two inverters contained in IC1 are used as audio amplifiers. IC1A amplifies consistently the signal picked-up by the small electret-microphone and IC1B acts as a band-pass filter, its frequency being centered at about 1.8KHz. The filter is required in order to select a specific frequency, the whistle's one, stopping other frequencies that would cause undesired be...

"The input to this unique device is our universally acclaimed High Impedance, Unity Gain, Class A, Buffer Preamp with it's superior RFI rejecting capability (to eliminate Radio Station interference) and Low Impedance output, allowing the use of extended cable runs from the G-2™ in bypass mode. The fixed High Impedance load presented to the Guitar allows the pickups to operate at their optimum, even when several effects units are connected after the G-2™. The Unity Gain Buffer also prevents "Ghost Distortion" being audible in Bypass Mode. This effect unit gets the most benefit from being fed into a clean, full frequency response amplifier and I recommend that when you receive your pedal you connect it up without anything else in line, just Guitar/Pedal/Amp, and discover the way the controls interact, both with themselves and the guitar/amp controls. Then adding the rest of your effects, you may find that you need to make slight adjustments to these as they are now...

Before lacquering the neck on our vintage Hofner Colorama II, we need to deal with the “Hofner” waterslide decal and the serial number stamped on the back of the headstock. Here’s what the serial number looked like before stripping the lacquer. And here’s how it looks afterwards: The “8” is hardly visible (although to be honest, it wasn’t stamped very deeply to start with), and in fact all of the numbers are in danger of becoming almost invisible once we add a few layers of lacquer. As it happens, I have a set of number punches, but they are a different size from the ones used on this guitar, which leaves us with two choices: sand the numbers off completely and re-stamp them, or try to repair what we already have. I’ve decided to go for the second option, since I feel a little weird about re-stamping serial numbers. Here we’re using a very small jeweler’s screwdriver as a kind of punch to deepen the outline of the numbers. The straight lines are easy, but the number 8 and the top of th...

This is a Simple Step-Up Converter For 20 LEDs circuit Project. The circuit described here is a step-up converter to drive 20 LEDs, designed to be used as a home-made ceiling night light for a child’s bedroom. This kind of night light generally consists of a chain of Christmas tree lights with 20 bulbs each consuming 1 W, for a total power of 20 W. Here, in the interests of saving power and extending operating life, we update the idea with this simple circuit using LEDs.  Power can be obtained from an unregulated 12 V mains adaptor, as long as it can deliver at least about 330 mA.  The circuit uses a low-cost current-mode controller type UCC3800N, reconfigured into voltage mode to create a step-up converter with simple compensation. By changing the external components the circuit can easily be modified for other applications. To use a current-mode controller as a voltage-mode controller it is necessary to couple a sawtooth ramp (rising from 0 V to 0.9 V) to the CS (current sen...

In the last blog post, we lacquered the neck on our vintage Hofner Colorama II guitar . Today we will paint the body. Before painting, we do a last check for anything we may have missed, like scrapes or gouges in the wood. This leads us to discover that the raw plug/screw anchor that someone had inserted to hold on the rear strap button, and which we were just going to leave, is, in fact, just half a raw plug. So, out it comes: A new hole is drilled: A wooden plug is cut: Glued in: And filed/sanded flat: Finally, we drill a new strap button hole: Et voilà. Also, since we're at it, let's drill a hole from the control cavity through to the tremolo area, so that we can earth (ground) the tremolo unit when we put this thing back together: Now on with the show. A quick mounting system needs to be fabricated, so we cut a piece of wood that can be attached to the neck pocket. We drill a hole in it too, so that we can hang it up. We’ll also put a screw in the rear strap button hole t...