Running LED with 4017

Running LED with 4017 complete with PCB layout. The series of 8 LED current is the basis for creating an 8-point LED. Slightly different from the running LED with IC 4017 (decade counter), 8 running this led is lit in sequence, but that has been previously flame does not die when the led is lit afterwards. 8 led to death after led to the fire-8. Meanwhile in the running LED (decade counter), the system LED lights like "point", there is only one LED that flashes between the tenth led.

The main component is the IC 74LS164 (SHIFT REGISTER), with its timer is astable multivibrator circuit (using IC NE555).

The series will be more efficient when using a stable power supply (regulator) using IC Regulator 7805. Under this scheme a series of stable power supply 5 volts dc.

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Logic Probe With Sound Circuit

This logic probe can be selected to operate on TTL or CMOS logic levels, depending on switch S1. A string of resistors associated with switch S1 sets the threshold levels for a window comparator comprising IC1a and IC1b. Depending on whether the level applied to the probe is high or low, the window comparator turns on LED1 (high) or LED2 (low). The 1.2M and 680k resistors set the probe signal to a midrange value when the probe is open-circuit, thereby preventing either LED from being lit.

Circuit diagram:

Logic Probe With Sound Circuit digram

If a pulse signal is present, the output of IC1a will toggle the clock input of flipflop IC2a. This drives LED3 which either lights for each pulse or continuously, depending on the setting of switch S2. Finally, the outputs of IC1a & IC1b are connected by diodes D5 & D6 to the base of transistor Q1 which is connected to the Reset input of flipflop IC2b. This has a piezo sounder (not buzzer) connected between its Q and Q-bar outputs so that it produces a sound which echoes the input pulse signal.

Author: Tom Hughes Copyright: Silicon Chip Electronics

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Timer with about 10 minutes

Applications of 555 timer IC is very diverse, one series of 10 Minute Timer with IC 555. 10 Minute Timer This circuit uses IC NE555 is set as a monostable multivibrator. The timing of the timer circuit 10 minutes with the IC 555 is governed by the configuration of C2, R4 and R5. The greater the value of C2 at 10-minute timer circuit with IC 555 timer is active then the time will stay longer. 

Total resistance value between R4 and R5 also determine the active circuit 10 minute timer with IC 555, where the greater the value the longer time was also active. The core active setting the timer on the set of C2 charging time for 10 minutes on the timer circuit with IC 555. So, with the value of C2 remain so with time on the circuit timing Timer 10 minutes by IC 555 can be set by changing the resistance value R 4 + R 5. Indicators of active timer at 10 minute timer circuit with IC 555 uses the LED D2 and D3 will light up only one course to identify the active timer and the timer has not been met.

Figure 10 Minute Timer circuit with IC 555

Description:

S1 is used to set / reset timer

R5 is used to set the timer to the desired time

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Basic Automatic Day Night Lamp with LDR

Automatic Day-Night Lamp wit LDR

Maybe its a lot who know how to work this one series, but I wanted to share back to the beginner on this. In the existing lighting circuit automatic lights that use components LDR (Light Dependence Resistor).



The workings of LDR LDR is exposed to light if the layer of the resistance was weakened likewise if there is no light at all resistance enlarged. here could make friends like that, because its components are a little easy but we will use the 220V AC voltage of course you must be very careful. Rather than actually being burnt. The author asks to be careful for the beginner course.

Schematic LDR

LDR components can be interconnected with a cable, so tools stay in the house but LDR is outside the home. It is recommended using qualified Relay no1 to avoid fire, because the relays are cheap to produce heat. Relay that cheap is not in use for high voltage. Travonya use the cheap, because this circuit does not require large currents. The function of Potensio 500KΩ to regulate Q1 & Q2 is on, if both the active transistor relay also participate actively.

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Stereo Preamplifier With Bass Boost

High Quality, simple design, DC 20v to 30v supply

This preamplifier was designed to cope with CD players, tuners, tape recorders etc., providing an ac voltage gain of 4, in order to drive less sensitive power amplifiers. As modern Hi-Fi home equipment is frequently fitted with small loudspeaker cabinets, the bass frequency range is rather sacrificed. This circuit features also a bass-boost, in order to overcome this problem. You can use a variable resistor to set the bass-boost from 0 to a maximum of +16dB @ 30Hz. If a fixed, maximum boost value is needed, the variable resistor can be omitted and substituted by a switch.

 Stereo Preamplifier With Bass Boost Circuit diagram:

Parts:
P1 = 10K
P2 = 100K
R1 = 100K
R2 = 100K
R3 = 15K
R4 = 10K
R5 = 22K
R6 = 15K
R7 = 1K
R8 = 470R
C1 = 2.2uF-25v
C2 = 2.2uF-25v
C3 = 470uF-35v
C4 = 1uF-35V
C5 = 2.2uF-25v
C6 = 47nF-63v
C7 = 22uF-25v
IC1 = TL072, Opamp
SW1 = DPST Switch
Notes:

• Schematic shows left channel only, but R1, R2, R3 and C1, C2, C3 are common to both channels.
• For stereo operation P1, P2 (or SW1), R4, R5, R6, R7, R8 and C4, C5, C6, C7 must be doubled.
• Numbers in parentheses show IC1 right channel pin connections.
• A log type for P2 ensures a more linear regulation of bass-boost.
• Needing a simple boost-in boost-out operation, P2 must be omitted and SW1 added as shown in the diagram.
• For stereo operation SW1 must be a DPST type.
• Please note that, using SW1, the boost is on when the switch is open, and off when the switch is closed.

Source : http://www.ecircuitslab.com/2011/06/stereo-preamplifier-with-bass-boost.html 

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Nokia 1100 Not Charging with beep

Nokia 1100 can not charging displayed with beep, please write PM first by UFS-3 Tornado, or other flashing box (Tuning Energy Management). If the problem not solved, go to trace charging circuit,

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