Speaker Protector Circuit with DC Protection

Speaker protector function to protect the speakers from damage caused by spikes in the audio signal when first turned on and the DC signal from the audio signal clipping. circuit protectors speakers consist of 2 parts which can protect the speakers are part of the DC signal detection and the delay. Part detetor DC signal composed by 4 pieces arranged diode bridge and a transistor. Then agian delay on the speaker is using a tank circuit protector in the form of capacitors, where the circuit composed of R6, C3, TR2 and TR3. End part of the speaker is using a relay protector. circuit protectors speakers in detail can be seen in the following figure.

Safety Speaker circuit

Component Speaker Protector Protection

Speaker circuit surge protector is equipped with a flashing indicator made ​​for the postponement of the power amplifier to the speakers. Speaker circuit surge protector can be used to protect the speakers in stereo audio system.

NE555 Touch Switch

The series of touch switch or touch switch is built by IC NE555, a series of touch switches can be used to turn on lights, alarms or other electronic equipment. This circuit uses 2 pieces of metal plate media as touch, MP1 (Metal Plate 1) and MP2 (Metal Plate 2). Touch switch circuit is equipped with a visual LED indicator for relay status (load active). To enable (Relay ON) can be done by touching the surface of MP1 and to turn it off by touching the surface of the MP2. MP1 and MP2 in touch this switch can use a small piece of copper (diameter 5mm) was enough.

Touch Switch series with NE555.

Component List 555 touch Switch
R1 = 3.3M
R2 = 3.3M
R3 = 10K
R4 = 1K
C1 = 10nF-63V
D1 = 1N4007
D2 = Red LED
Q1 = BC547
IC1 = NE555
RL1 = 12V Relay

Interface Relay with PNP transistor

One technique relay drivers from the microcontroller or computer can be made with the driver PNP transistors like the article "Interface Relays With PNP Transistor" ini.This circuit interface is simple and easily applied to a microcontroller or computer parallel port. Interface Relays With PNP Transistor uses 2 transistors 2N3904 and 2n2905/2N2907 UAH as a power relay drivers. The advantages of this circuit can menggeran relay with considerable power with TTL logic input from the computer and microcontroller. Source voltage required to follow the relay circuit is used, for example using a 12V relay, the source voltage to 12V or 24V relays the 24V voltage source. Detailed relay interface circuit and microcontroller or computer can be seen in the following figure.

Function diodes mounted parallel with the relay to prevent backflow into the transistor due to magnetic induction of the relay coil, therefore these diodes must be installed. For installation with a microcontroller or computer which need to be noticed is the Grund computer or microcontroller circuit must be connected to ground in series Interface Relays With this PNP transistors.

Switch With Relay Schematic

Light Switch With Relay is a series of electronic switches that are controlled by a series of light received. Light Switch With Relay circuit can be used to control lighting automatically, so the lights can automatically turn on when the room light or the region began to decrease. Limit of light used to activate the electronic switch in the circuit Light Relay Switch With This can be set via the potentiometer P1. P1 setting is basically a light reception sensitivity settings. Light Switch With Relay circuit uses the LDR as the light sensor and an IC 741 as a comparator and reference voltage sensor, relay driver transistor Q1 as as an electronic switch. A complete range of Light Switch With Relay is as follows.

Circuit Light Relay Switch With diats a light switch that will be active when the sensor does not receive light, if you want to turn the tables (the active switch when the sensor receives light) it can be done by reversing the position between the LDR and R1. Diodan D1 serves to avoid the effects of EMF or sparking of the relay coil. The circuit is simple and easy to make, I hope to provide ideas and descriptions in the manufacture of a controlled light switch. Hopefully useful.

Solid State Relay Circuit

Solid state relay is a series of hibryd that serves as a mechanical relay. Solid state relays is built with insulating an MOC to separate the input and the switch. Solid state relay with us to avoid the occurrence of sparks as it does on conventional relays can also avoid the occurrence of the connection is not perfect because the porous contactor as in conventional relays. Solid state relay circuit is quite simple and we can make in a PCB hole. For more details can be seen in the picture following a series of solid state relays.

Solid state relay has many advantages including no mechanical friction on the contactor, the connection process only occur when there are crosses zero, there is no spark at the contactor, not noisy, small consumtion flow control, better endurance.