Near to anniversaries of the birth of my son is 6 years old. What should I buy as a gift for him. My son’s favorite toys with the idea.Because he has a good imagination. What toys are not boring?
The player can create a story that does not end.
When I consider the best. Just choose toys of the Building Sets.
It has a very But my son likes the police and the home or building.
I found LEGO Police Station 7498. It exactly as his needs.

Below are the details.

Stop the prisoners from escaping the police station through the pipe drain! They won’t get far on foot. Use the police car to chase them down and transport them back to prison in the police van. Help keep LEGO City safe with this feature-packed set! Includes police car, prisoner transport van, and bicycle.

If you are interested to buy your children, read more.

This is versatile digital counter circuit, that as a cheap due to basic components you can buy in many electronic shop. My friend said the some circuits that price same this circuit may be not worth it. You can apply too much model as you want with special feature of this circuit following.
1.A count up or count down the time.
2. Can connect output to a 7 segment LED both a Cathode common or Anode common.
3. Can store a collection of information
4. Can set number counting in advance.

In circuit as figure 1 is shown normal operation, by set the circuit are 2 main, that if we want more than this, it can be connected together to added unlimited.

Figure 1 is A versatile and cheap digital counter circuit

The heart of the circuit is composed of 2 parts.
1. A decoder and drive LED display.
2. The counter number on the Binary Code Decimal Output that use IC2-CD4510

Source:

LM2576-5.0 is simple switching power supply 3A step down regulator for power digital circuits.

Sometimes we need to work on the car or travel outside the area. The without wires internet ADSL. When use the Internet was Using 3G aircards and distributed to the Internet via wireless. It uses the power supply of 5V 2A. Because it is digital circuit which uses a 10 watt high power ever.

When it comes to used in cars. We can uses power from the cigarette lighter of a car.But have the voltage 12 volts, so it must reduced the voltage down to 5 voltsat current is 2 amperes. We have a lot of choices. When before I use the transistor and IC-7805 for this job. However, when considered with caution. To its low performance. have high temperature and large, as the identity of the generally linear ICs. This work, we try to do the switching IC.

IC-LM2576-5.0. (DC to DC step down voltage regulator) It is a very interesting number. It maintains a constant the voltage of approximately 5 volts and current 3A. Compatible with the device easily. On the manufacturer’s manual. I smile with ease. It is very easy to use. as Figure 1. Will see that, there are only four more devices only are C1-100uF , D1-1N5822,L1-100uH, C2-1000uF. The input voltage levels is 7volts to 40volts. My favorite feature is the runs with high frequency. IC is not hot. It can hold a small cooler. And Used continuously for a long time.

Sorce:

Here is circuit switching regulator 5V 5A for digital circuit.
Use IC LM2678-5.0 is High Efficiency 5V 5A Step-Down Voltage Regulator This is good power supply, small size and do not hot.

Friends want to build the digital power supply which this circuit “Top Linear power supply regulator 5V 5A with 7812 and LM723” is good quality, but as the too old circuit. Not suitable for this era. So I to find a new and very powerful also an Energy savings.
Considering these reasons. We will Using an ICs Switching supply. Because of has very high performance. High energy, while the low energy input.
LM2678 can respond to fully our needs. We can supply approximately 5A. The circuit and very easy to use. See information on the manufacturer’s manual, very easy to understand explanations. It uses a little equipment is only 9 pieces. And Cin = 3x15uF 50V, C2-0.47uF 63V , C3-0.01uF 63V , D1 – 6TQ045S, L1-22uH, Cout=2x180uF 16V as figure 1
Advantage of this range is very wide input voltage. From 8 vots to 40 volts DC power and does not need to be very smooth. But must be have the current 5 A or more.And this circuit high performance. Generate heat loss at low IC can use a small cooler (heat sink).

Source : 97 Electron Circuit

source:

This is circuit Simple DC Voltage Regulator By Transistor C1061. (easy circuit)
by this circuit can give Voltage go out about 12V, depend on Zener diode or ZD1 usual use 12V values thus. When you use other value 9V such as get Voltage about 9V also. And this circuit still give current output about 1A depend on transformer. The detail is other request you see in image circuit.

If you the hight current than top circuit. you can be try make this circuit, it can provide the 2 Amp current with 2N3055 transistor.

DC 12V to DC 6V-7.5V-9V Converter using 2N3055

This circuit is DC to DC converter model step down voltage. That can modify voltage input 12V DC from be DC 6V , 7.5V and 9V by have the size current about 1A – 2 Amp think. Be easy circuit use Zener diode maintain one’s position voltage. Be stable and have transistor 2N3055. When you several examples of the output voltage 6Vout, R1 =330 , ZD1=6.6V ; 7.5Vout, R1 = 270 , ZD1 = 8.2V ; 9Vout , R1=180 , ZD1=10V ; Perform enlarge the trend tallly go up fully be usable next , see the detail in the circuit and read to add