REACTION TIMER GAME

REACTION TIMER GAME
This is a game for two players.
Player 1 presses the START button. This resets the 4026 counter chip and starts the 555 oscillator.
The 555 produces 10 pulses per second and these are counted by the 4026 chip and displayed on the 7-Segment display.
The second player is required to press the STOP button. This freezes the display by activating the Clock Inhibit line of the 4026 (pin 2).
Two time-delay circuits are included. The first activates the 555 by charging a 10u electrolytic and at the same time delivering a (high) pulse to the 4026 chip to reset it. The second timer freezes the count on the display (by raising the voltage on pin 2) so it can be read.

Clap Controlled Electronic Switch

Description

This electronic switch allows you to control an electronic device by only clapping your hands twice. It is based on three integrated circuits; 741 Op-Amp, 555 timer, and 4013 dual D flip-flop.
A 9V battery is ample to operate the circuit.
When you first clamp your hands, mic detects the sound and triggers the 555 timer via the operational amplifier. The timer stretches the signal and applies it to the clock input of the flip-flop. Because of the three state arrangement of the flip-flop , one more clamp is needed to change the output state. Second clamp sets the flip-flop output to high and this forward biases the 2N2222 BJT. Relay closes so the device connected to the relay switches on. Same procedure applies for the opposite. When you clap your hands twice, relay closes and turns off the device connected to it.
R3 trimpot adjusts the sensitivity of the circuit. You should turn it till the room noise does not effect the switch operation.

Components

IC1: 741 Op-Amp

IC2: 555 Timer

IC3: 4013 Dual D Flip-Flop

Q1: 2N2222 NPN Transistor

C1, C2, C3, C4: 0.1uF Ceramic Capacitor

C5: 47 uf Electrolytic Capacitor

R1, R2, R4, R5, R10: 10 KOhm

R6: 150 KOhm

R7, R9: 100 KOhm

R8: 1 MOhm

R11: 220 Ohm

R3: 100 KOhm Trimpot

B1: 9 Volt Battery,

K1: SPST Reed Relay 5 Volt DC Coil

MIC: Electret Microphone

Time delay Relay circuit with IC555

Parts List
C1 10uf 16V Electrolytic Capacitor
C2 0.01uf Ceramic Disc Capacitor
R1 1 Meg Pot
R2 10 K 1/4 Watt Resistor
D1,D2 1N914 Diodes
U1 555 Timer IC
RELAY 9V Relay
S1 Normally Open Push Button Switch
Remark:
1. We used R1 adjusts the on time.
2. You can get a different capacitor for C1 to change the maximum on time.
3. S1 is used to activate the timing cycle. S1 can be replaced by a NPN transistor so that the circuit may be triggered by a computer, other circuit, etc.

5 to 30 Minute Timer Circuit

Descriptipn:

A switched timer for intervals of 5 to 30 minutes incremented in 5 minute steps.

Circuit diagram

Notes:
Simple to build, simple to make, nothing too complicated here. However you must use the CMOS type 555 timer designated the 7555, a normal 555 timer will not work here due to the resistor values. Also a low leakage type capacitor must be used for C1, and I would strongly suggest a Tantalum Bead type. Switch 3 adds an extra resistor in series to the timing chain with each rotation, the timing period us defined as :-

Timing = 1.1 C1 x R1

Note that R1 has a value of 8.2M with S3 at position "a" and 49.2M at position "f". This equates to just short of 300 seconds for each position of S3. C1 and R1 through R6 may be changed for different timing periods. The output current from Pin 3 of the timer, is amplified by Q1 and used to drive a relay.

Parts
Relay 9 volt coil with c/o contact (1)
S1 On/Off (1)
S2 Start (1)
S3 Range (1)
IC1 7555 (1)
B1 9V (1)
C1 33uF CAP (1)
Q1 BC109C NPN (1)
D1 1N4004 DIODE (1)
C2 100n CAP (1)
R6,R5,R4,R3,R2,R1 8.2M RESISTOR (6)
R8 100k RESISTOR (1)
R7 4.7k RESISTOR (1)

author:Andy Collinson, mailto:anc@mitedu.freeserve.co.uk
website: http://www.zen22142.zen.co.uk

Circuit explanation for 555 timer

Circuit explanation for 555 timer

Block diagram

NE555 is composed of the voltage comparators, the flip-flop and the transistor for the discharge. The composition is simple, but it is excellent one.
Three resistors are connected with the inside in series and the power supply voltage(Vcc) is divided in 3. This composition is an excellent point. 1/3 with power supply voltage is applied to the positive input terminal of the comparator (COMP1) and the voltage of 2/3 is applied to the negative terminal of the comparator (COMP2). When the voltage of the trigger terminal(TRIGGER) is less than 1/3 of the power supply voltage, the S terminal of the flip-flop(FF) becomes H level and an FF is set. When the voltage of the threshold terminal(THRESHOLD) is more than 2/3 of the power supply voltage, the R terminal of the FF becomes H level and an FF is reset.

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The oscillation operation explanation

I will explain the circuit operation below.

The condition immediately after the turning on

The condition when turning on the power becomes the condition which is shown in the figure on the left. The L is 0 V almost, showing the low level. H is the value which is high level and is near Vcc. The flip-flop (FF) is the SR type. The Q becomes H and becomes the L when S becomes H. After that, even if S becomes the L, the Q maintains H and maintains the condition of the L. When R becomes H, becomes H and the Q becomes the L. That is, the Q becomes H when a few S become H(the set) and the Q becomes the L when a few R become H(the reset). When S and R become H at the same time, the condition of the Q and is unsettled. (I think that both become H). Because is H in this condition, TR is in the ON condition and the collector (C) of TR is in the L condition. Therefore, the electric charge doesn't store up in capacitor(C), the (+) terminal with the voltage comparator(COMP2) doesn't cross V2. Because it is, the output of COMP2 is as the L and the FF doesn't become the reset condition. OUT is as the L condition.

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The timer start condition

When the start switch (SW) is pushed, the COMP1 (-) terminal becomes the L condition.
Because the voltage of the COMP1 (-) terminal became equal to or less than V1 of the (+) terminal, the output of COMP1 becomes the H condition.
With this, the FF becomes the set condition, the Q changes into H, changes into the L condition and OUT becomes the H condition.
Because became the L condition, TR becomes the OFF condition. When TR becomes the OFF condition, the electric charge begins to store up in capacitor(C) through the resistor (R). As the electric charge stores up in capacitor(C), voltage of the both edges of capacitor(C) begins to go up. The start switch (SW) uses the non lock type which turns back after pushing once. In case of being as the pushed condition, OUT doesn't become the L condition even if the timer does in the time-out. When the start switch (SW) turns back, the COMP1 (-) terminal becomes the H condition and to become equal to or more than V1 of the (+) terminal, the output of COMP1 becomes the L condition. The output of COMP1 becomes the L condition and the S terminal of the FF becomes the L condition, the condition of Q and of the FF don't change. While the voltage of capacitor(C) doesn't exceed the voltage V2(the voltage of the COMP2 (-) terminal), FF maintains this condition.

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The time-out condition

The output of COMP2 becomes the H condition when the electric charge stores up in capacitor(C) and the voltage of the COMP2 (+) terminal crosses V2 of the (-) terminal. The reset terminal (R) of the FF becomes the H condition with this, the Q becomes the L and becomes the H condition. OUT becomes the L condition.
Because becomes the H condition, TR becomes the ON condition. Because TR becomes the ON condition, the COMP2 (+) terminal becomes the L condition and the output of COMP2 returns to the L condition. So, the condition of the Q and don't change, OUT is as the L condition. Also, because TR becomes the ON condition, discharge through TR by the electric charge of capacitor(C) and the electric charge of capacitor(C) passes away.

By above operation, it returned to the condition before pushing the start switch.