Mutchus

Description You can save on your electricity bills by switching to alternative sources of power. The photovoltaic module or solar panel described here is capable of delivering a power of 5 watts. At full sunlight, the solar panel outputs 16.5V. It can deliver a current of 300-350 mA. Using it you can charge three types of batteries: lead acid, Ni-Cd and Li-ion. The lead-acid batteries are commonly used in emergency lamps and UPS. The working of the circuit is simple. The output of the solar panel is fed via diode 1N5402 (D1), which acts as a polarity guard and protects the solar panel. An ammeter is connected in series between diode D1 and fuse to measure the current flowing during charging of the batteries. As shown in Fig. 1, we have used an analogue multimeter in 500mA range. Diode D2 is used for protection against reverse polarity in case of wrong connection of the lead-acid battery. Charger circuit diagram: When you connect wrong polarity, the fuse will blow up. For charging a l...

One tool that I’ve been missing at my lab at home is function generator. They tend to be a bit expensive, so I haven’t bought one. I thought this might be a good opportunity to try and make one myself. I found a pretty common DDS (direct digital synthesis) chip, called AD9833. Then just strap a USB-enabled AVR micro there and maybe some analog electronics.   This board doesn’t do any of the special analog magic to allow for variable amplitude or offset for the signal. The output is fixed to 0-4v. I’m planning to make another completely analog board for adjusting amplitude and offset. [ ]

This adapter circuit can deliver up to 3A output voltage of 12V. The circuit can be used in cases when a current of more than 3A is required for the controller. IC regulators such high current rating are quite hard to find. The T1 transformer steps down the voltage of the rectifier bridge 12rms and D1 to produce a rectified voltage. The C1 filters the output of the rectifier produces a DC level. The passage of the series transistor Q1 (2N 3055) is biased by resistor R1 (680Ω). Since D1 is Zener breakdown region of the voltage across it is 12V. So the total output voltage of 12.7 V is constant (in theory). Zener voltage which is the most base emitter voltage of transistor Q1 Q1.Here take out the excess power needed. Notes . If 12V zener is not available ,use the nearest value. The transformer T1 can be as 23oV primary;15V/5A secondary step down transformer. The capacitors must be rated at least 25V. By changing the value of the Zener diode, different output voltages can be obtained f...

SMPS and Horizontal scan output schematic – LG29CC2RL 29 inch CRT TV Circuit diagram [ Click on the schematic to magnify ]

Build a 15W Bridge Audio Amplifier Circuit based TDA2002 . 15W bridge audio amplifier circuit which use 2 pieces of TDA2002. This is audio amplifier for general, work with a single power supply. Use 2A power supply transformer for maximum performance and heatsink should be used to keep the IC from overheating. Build a 15W Bridge Audio Amplifier Circuit based TDA2002 Component part list: R1-5 = 2.7? R2 = 100? R3-4 = 2.2? R6 = 220? R7 = 1M? TR1 = 100K? trimmer C1-9 = 10uF/16V C2-8 = 220uF/16V C3-4-5-7 = 100nF/63V C6=470uF/25V IC1-2=TDA2002 Lsp = 4 – 8?/40W Loundspeaker

Very often when enjoying music or watching TV at high audio level, we may not be able to hear a telephone ring and thus miss an important incoming phone call. To overcome this situation, the circuit presented here can be used. The circuit would automatically light a bulb on arrival of a telephone ring and simultaneously mute the music system/TV audio for the duration the telephone handset is off-hook. Lighting of the bulb would not only indicate an incoming call but also help in locating the telephone during darkness. Circuit diagram : Telephone line Based Audio Muting and Light-On Circuit Diagram On arrival of a ring, or when the handset is off-hook, the inbuilt transistor of IC1 (opto-coupler) conducts and capacitor C1 gets charged and, in turn, transistor T1 gets forward biased. As a result, transistor T1 conducts, causing energisation of relays RL1, RL2, and RL3. Diode D1 connected in antiparallel to inbuilt diode of IC1, in shunt with resistor R1, provides an easy path for AC cu...

Here is the circuit of a Class B audio amplifier based on TDA1553 . TDA1553 is a monolithic audio amplifier class B, containing 2 x 22 watt amplifier in bridge configuration load attached. The amplifier operates from 12V DC and develops intentionaly for car audio applications. The IC also has a lot of good features such as short circuit protection, protection of the load dump, reverse polarity protection, speaker protection, etc. In the circuit, C5 and C4 are decoupling capacitors C3 input, while setting the delay for speaker protection. C1 and C2 are filter capacitors of the offer. Notes : Assemble the circuit on a good quality PCB. Use 12V DC for powering the circuit. The circuit can deliver 22W per channel into 4 ohm speakers. Fit the IC with a proper heat sink.

I have a couple of front door LED lights which I would like to switch on automatically during the evening/night. The two conventional methods that are commonly available had their disadvantages: A timer switch is the easiest and cheapest solution, but doesn’t take into account day light savings. Besides that, in Einhoven, the Netherlands where I live in december the sun sets around 16:30 while in June it doesn’t get dark before 22:00. A simple timer doesn’t take that into account either. Since you only want the lights on when it gets dark, instead of time you can also use a light sensor to distinguish day and night. You have these front door lights that have this built in. The problem that I had with these devices is that they start bouncing (‘flickering’) around sunset/sunrise. They constantly turn on/off which causes damage to the LED lights I was using. This cost me already several expensive led lights. [ ]