Flasher With Beeper

Here is the simple but interesting project flasher with beeper, can be used in automobile and other application. It can be used as flasher beeper in scooter, motorcycle etc where there is no facilities of beeper with flasher.

Working of the circuit of flasher with flasher with beeper

The heart of the circuit flasher with beeper is IC₁ (LM 555) which is used as 1 kHz astable multivibrator. When the circuit flasher with beeper is connected to the power (from turn indicator switch of scooter), output of 1 kHz frequency is obtained from pin number 3 of IC₁ (LM555). This frequency is given to speaker through R₃ and C₂ and beeper sound is heard.

Using Method of flasher with beeper

The circuit of flasher with beeper can be used only to those vehicles, having the facilities of Turn Indicator Switch. Connection diagram is shown in figure 2. Two signal diodes is connected to left and right side each of switch and connected to point A (for power supply).

PARTS LIST

Resistors (all ¼-watt, ± 5% Carbon)

R₁ = 4.7 KΩ

R₂ = 10 KΩ

R₃ = 68Ω

Capacitors

C₁ = 100 KPF (104 ceramic)

C₂ = 10 µF/10V

Semiconductors

D₁, D₂ = 1N4007

IC₁  = LM555 Timer IC

Miscellaneous

Speaker 8 Ω

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Sound Operated Music Bell

Sometimes ringing the bell manually becomes difficult, especially when you are holding something in your hands. The sound-operated music bell takes care of the problem

In this circuit, the use of an external relay has been eliminated. The circuit comprises a trigger stage (around BC548B), a timer stage (NE555) and a melody stage (around UM66 and SL100).

Transistor BC548B is biased inn class C operation. Every second sound cause triggering at pin 2 of 555 timer IC.

When VR₁ is at maximum, the hold-on time of NE555 is around 30 seconds. But this time period can be set to a lower value by VR₁, as per requirement, using the relationship.

T = 1.1*VR₁*C₁

Where VR₁ is the actual resistance of the preset in circuit. UM66 IC has  ROM memory of 64 notes which are produced one by one and then over with a sound of a clap, the timer is triggered and the output at pin 3 of IC NE555 goes high which gets applied through diode 1N4001 to pin 2 of musical IC UM66. S UM66 gets the positive supply, it starts giving electrical fluctuations of the music to the base of SL100, and the charming music comes and fed to 4-ohm speaker.

PARTS LIST

Resistors (all ¼-watt, ± 5% Carbon)

R₁ = 10 KΩ

R₂ = 470 KΩ

R₃ = 2.2 KΩ

R₄ = 150 KΩ

R₅ = 100 Ω

VR₁ = 1 MΩ

Capacitors

C₁ = 22 µF/16V

C₂ = 0.1 µF

C₃ = 0.22 µF

C₄ = 220 µF/10V

C₅ = 0.01 µF

Semiconductors

IC₁ = NE555

IC₂ = UM66

T₁ = BC548B

T₂ = SL100

D₁ = 1N4001

Miscellaneous

MIC₁ = Condensers microphone 34 LOD

SW₁ = On/Off switch

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Light Alarm Circuit with LDR

 This musical light alarm circuit is very simple, uses only 7 components, a LDR and a 3.6 V battery or 3 x 1.2 volts rechargeable batteries. The well-known UM66 is used as the sound generator and will give a pleasent wake up alarm

As you probably know the LDR is a light dependent resistor. Normally the resistance of an LDR is very high, sometimes as high as 1MΩ, but when they are illuminated with light resistance drops dramatically. In the circuit adjust the 220KΩ preset to the desired sensitivity, meaning adjusting the threshold point where the alarm start singing.
When there is light on the light dependent resistor the T1 transistor will start conducting and powers the UM66 musical integrated circuit. The produced musical note will be amplified by transistor T2 and fed into the 8Ω speaker.
On the UM66 IC are different numbers, each number giving a different musical note (in this example we use UM66T). You may use 2 x 1.5V batteries but 3 x 1.2V NiCad or NiMH are better because you can recharge them.

http://learnlineweb.com/

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LDR Pole Light Switch

My vintage (62 year old) pole light has always been controlled by a timer—a source of continual frustration due the requirement of readjustment for the ever-changing seasons. However, after knocking it over (I backed my car into it…), I decided it was time for an update. The circuit consists of a light dependent resistor (LDR), TLC555 (applied as Schmitt trigger), and a TRIAC power switch. The complete assembly neatly fits inside the steel pole light tube and the LDR peeks out through a hole in the side. This was really a fun project, and useful to boot.

Power supply
The power supply is the typical capacitor limited charge pump type that is zener regulated at 6.2V. Due to the lack of isolation, I was careful to identify the return conductor so that the electronics (including the LDR) would not be floating on the hot lead. For safety, most of the testing was done using an isolation transformer. R1 must absorb a high peak power transient current when power is applied, so a carbon comp, ceramic comp, or wire wound resistor is recommended. Maximum DC current available is 16mA. Actual load is about 6mA. My application was 115V, 60hZ. For 230VAC, the components are indicated on the schematic. In this circuit, +6V is the power return lead, and 0V is the electronic circuit common—to visualize this, one must screw his head on backwards…
LDR
The light dependent resistor (CdS photocell) that I used was in the TO-5 package that is well adapted for poking through a hole and is held in place with silicone rubber. The Clairex CL703M19 LDR that I used is no longer available and I have been unable to locate the specs. The DigiKey PDV-P8103-ND appears to be a reasonable choice, but may require bias current tweaking to set the threshold.
555 Schmitt trigger driver
A TLC 555 was used as a voltage threshold detecting device with hysteresis. Pin 7 drives the TRIAC gate directly via its open collector output. This is a rather unconventional application. The CMOS version is used to minimize power supply load—I tried a bipolar 555 and it worked, but the power supply ripple voltage doubled to about 0.5VP-P.
Constant current bias—Threshold adjustment
Because the 555 has so much hysteresis, I feared that the ON & OFF thresholds would be too far apart. To help reduce the hysteresis, the LDR is biased by a current source. Q1 is wired as a current source—its collector current does not vary with collector voltage. This technique essentially increases the “gain” of the LDR. The current is set via adjusting the emitter resistor (R3)—it drops about 0.37V.
C3 makes the circuit insensitive to rapid changes in light intensity. It takes about 60sec to turn on.
Logic TRIAC
The logic TRIAC is an interesting device. It can be triggered by either a positive or negative gate current regardless of voltage blocking polarity. For maximum sensitivity, I used negative gate current. The device I used had an actual Igt (gate current sensitivity) of 1.5mA that is well below the 5mA Max specification. However, gate overdrive (5mA in my case) is recommended to assure that it fires at low winter temperatures. Quencharc RC-1 is connected across the TRIAC to help control turn-off voltage transients.
Choice of lighting
For the time being, I am sticking with the vintage incandescent lamp—it is a matter of aesthetics. I will upgrade to LED technology only when its color balance matches incandescent.

Made By:Muhammad Zubair Aslam
Email:   zubairaslam719@gmail.com

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