Tuesday, April 30, 2013

Cross Linking With Two Patch Cables

In networks, the supremacy of coax cable is a thing of the past. Nowadays, Ethernet connections are made using UTP cables. The BNC plug has yielded to the 8-way RJ45 plug. Previously, coax cables were daisy-chained from computer to computer and terminated at the two ends using 50-_ resistors, but modern networks use central ‘socket boxes’ (switches and/or hubs) to interconnect everything. The connections between the hubs and the computers are made using patch cables having the same sequence of leads in the RJ45 connectors at each end. For making a direct connection between two computers without using a hub or switch, a ‘crossover cable’ is used.

Cross-Linking With Two Patch Cables
Cross-Linking With Two Patch Cables
Cross-Linking With Two Patch Cables
Cross-Linking With Two Patch CablesSuch a cable has the leads cross-linked in order to allow the two computers to directly communicate with each other. If there are problems with the network, it can be handy to be able to directly interconnect twocomputers, or directly connect a computer to a cable or ADSL modem without using a hub or switch. A long crossover cable is not always available, and shoving around computers is not an attractive alternative. Consequently, we can use a dual RJ45 wall outlet box to construct an adapter, which can be used to interconnect the two patch cables coming from the equipment in question. This outlet box must be wired to create a cross-linked connection. This is done by making the following internal connections:
  • 1 → 3
  • 2 → 6
  • 3 → 1
  • 4 → 4
  • 5 → 5
  • 6 → 2
  • 7 → 7
  • 8 → 8
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New Dark Activated Terrace Lamp

This device allows one or more lamps to illuminate at sunset and turn off at dawn.Q1 and Q2 form a trigger device for the SCR, providing short pulses at 100Hz frequency. Pulse duration is set by R2 and C1.When the light hits R1, the photo resistor assumes a very low resistance value, almost shorting C1 and preventing circuit operation. When R1 is in the dark, its resistance value becomes very high thus enabling circuit operation.

 Circuit Diagram:
Dark Activated 220 volt AC Lamp Circuit Diagram
 

Parts:


R1 = LDR
R2 = 100K
R3 = 200K
R4 = 470R
R5 = 12KR6 = 1KR7 = 470R
C1 = 10nF-63V
D1 = TIC106D
D2 = 1N4007D3 = 1N4007D4 = 1N4007
D5 = 1N4007
Q1 = BD327
Q2 = BD337
SK1 = Female Mains Socket
 
Notes:

  • R3 allows fine setting of operating threshold and R2 value can be raised to 150K maximum.
  • Several lamps wired in parallel can be connected to the circuit, provided total power dissipation of the load does not exceed about 300 - 500W.
  • PL1 can be omitted and the input mains supply wires connected in parallel to any switch controlling lamps. In this case, if the switch is left open, the circuit will be able to drive the lamps; if the switch is closed, the lamps will illuminate and the circuit will be by-passed.
  • Warning! The circuit is connected to 230Vac mains, and then some parts in the circuit board are subjected to lethal potential! Avoid touching the circuit when plugged and enclose it in a plastic box.
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Sunday, April 21, 2013

Stream powers Soldering Iron

The article can guide you on how a soldering iron is made on your own. Moreover, itll not value you an excessive amount of. scan on to grasp a lot of.



The soldering iron could be a battery operated one. A relay is added in order that the battery is turned off once the adaptor is plugged to a socket. A soldering iron is needed to solder the battery holder, switches and also the wires. If a soldering iron isnt offered, the wires is twisted along and lined using insulation tape. however this could not be the simplest approach.

The hardware needed for this project is listed below:
Soldering iron tip
6V battery holder
A Switch
Wooden box
E-10 lamp base
Soldering iron
Solder

Firstly, the look ought to be created. Since the iron will hande solely a current of regarding one.7 amps, parts that take plenty of current shouldnt be used. All the parts are mounted in an exceedingly wood box. This makes it moveable and simple to use. In case this must be reworked into a plug in iron, all that must be done is to switch the battery pack with a six volt DC wall wart.




Thats it. The soldering iron is currently able to be used. The circuit is changed to suit any specific necessities.
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stream powers low cost Macro Lens

For all photography and video enthusiasts, a macro lens is quite simply a basic necessity. A macro lens is incredibly helpful to produce detailed pictures of tiny objects or options. despite the fact that nearly each photographer or video recorder wants one among these, theyre quite expensive and hence not everybody will afford it.



Nevertheless, theres the simplest way to create yourself a macro lens. Everything may be achieved by using any lens, 2 plastic bottles, super glue, and duct tape. A photography or video device to that the lens has got to be connected is additionally needed.

1st of all, the neck of a bottle is cut employing a hot knife. Another piece of plastic thats the same as the form of the bottle’s neck is cut out from a special bottle. This plastic section is placed at the lowest. This forms the bottom on that the lens can ought to be placed.



The lens are held near the bottle neck using super glue. once holes are created at applicable positions at each ends of the device, its currently able to be connected to any camera. It may be connected permanently using super glue, or quickly with some duct tape.

The lens device are placed directly over the quality lens, permitting the camera to require a definite photograph of tiny options using the first programming.
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Saturday, April 13, 2013

Power Indicator for the Water Softener

This power indicator circuit is intended to be used as an extension for the water softener. It might be easier to just place a LED but it is better to make a rectifier that detects the presence of the 15 kHz signal generated by the 555 IC.

Water Softener Power Indicator Schematic

water softener power indicator schematic
The rectifier is connected at the water softener system with C4 capacitor. D1 and D2 diodes are used to obtain a DC voltage that is filtered by C5 capacitor. This voltage turns ON the FET that lights up the LED. When there is no signal from the oscillator the LED will not glow. D1 and D2 = 1N4148.
NE555 datasheet
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Transistor As a timer circuit

Basically on all timer or timer circuit utilizing most of the basic characteristics of the capacitor.

Transistor As a timer circuit

 The basic characteristic is the process of filling and discharge that occurs in the capacitor. The length of time charging and release depends on the value of the capacitor.


If we observe the above circuit, the light will immediately switch SW1 turns on when we plug it into potensio VR1, this is because the current flowing from VR1 to trigger the transistor base should fill the first capacitor C1. Semakian large capacitance value of C1 then the longer the time required by the transistor to turn on the lights. Then if we connect it to the Ground SW1 then light would soon die and the capacitor will immediately clear the cargo. So can we draw the conclusion that the transistor can be used as a timer circuit using capacitor charging and discharging properties.
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Introduction to MatLab Circuit Analysis

Introduction MatLab can be a useful tool in many applications. We will learn how to analyze a simple electrical circuit, set the problem up as N equations in N unknowns, and transform the equations into a matrix formulation that MatLab can solve. Introduction to MatLab: Circuit Analysis 3 Topics Topics Electrical Devices. Electrical Devices. Kirchhoff’s Laws. Kirchhoff’s Laws. Analyzing a Resistor Network. Analyzing a Resistor Network. Inverting Matrices. Inverting Matrices. A MatLab Solution. A MatLab Solution… Voltage and Current Voltage -the force that pushes electrical Voltage -the force that pushes electrical current around a circuit. (Sometimes current around a circuit. (Sometimes called “potential” as in potential energy.) called “potential” as in potential energy.) Current -the flow of electrical charge Current -the flow of electrical charge through a conductor.

Click here to download Introduction to MatLab Circuit Analysis
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