e02ch17.pdf

(86 KB) Pobierz

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">

SMALL CIRCUITS COLLECTION

017

Carnival Glasses

By now we know that circuits that

generate light effects or sound

effects can always count on a large

group of interested readers. Conse-

quently we present here yet another

simple running-light display, this time

designed such that it can be fitted

into a pair of ‘carnival glasses’. This

means that the party lovers among

our electronics hobbyists have

something to satisfy their interests.

The details of the actual implemen-

tation are naturally a question of

personal taste, but for the prototype

we thought it a nice idea to distrib-

ute the total of 16 LEDs over the

frame such that the running lights

move in mirror image over the two

halves of the glasses (D1 on the left,

D2 on the right, D5 on the left, D6 on

the right and so on). Of course,

everyone is free to decide exactly

how to build the running light display. Due to its small size,

this circuit is also quite suitable for ﬁtting into an illuminated

brooch or button.

The oscillator built around IC1d is about the simplest imagin-

able Schmitt-trigger type using a 4093 gate. The frequency

can be varied by a factor of approximately ten using poten-

tiometer P1 (roughly speaking, the frequency is a few Hertz).

You can also experiment with other values if necessary. The

oscillator drives a ﬁve-stage Johnson counter, which always

has only one active output. Here we have

assumed a total of 16 LEDs in groups of four,

so there is always one group on and three

groups off. The fifth output immediately

resets the counter, causing the ﬁrst output to

again become active.

The circuit is powered by a 9-V battery.

Depending on the manufacturer, the voltage

drop across each LED is more than 1.7 V. If

we still want to see something with a nearly

empty battery, we thus cannot connect more

than four high-efficiency LEDs in series. Since

only one row of LEDs is on at once, a FET

wired as a simple constant-current source

(T1) ensures that the brightness remains

good for as long as possible. T1 also pre-

vents excessive current (more than around 4

mA) from ﬂowing when the supply voltage is

relatively high.

Fit the LEDs into holes drilled to ﬁt and secure

them with two small drops of glue each. The wiring can also be

attached in a creative manner. Only five wires are required

between the glasses and an external enclosure containing the

circuitry and battery. A small control potentiometer can be

used for P1, so that the speed of the LEDs can be easily

adjusted after everything has been ﬁtted into the enclosure.

(024117-1)

14

IC1 = 4093

C2

IC1

BT1

100n

7

9V

D1

D2

D3

D4

16

3

2

0

1

2

3

4

5

6

7

8

9

CTRDIV10/

D5

D6

D7

D8

DEC

14

4

&

IC1.D

7

+

13

12

11

13

10

&

D9

D10

D11

D12

1

IC2

5

4017

6

P1

D13

D14

D15

D16

9

1M

R1

100k

1

2

15

11

3

IC1.A

&

CT=0

12

CT ≥ 5

5

6

4

IC1.B

C1

T1

&

8

1

µ

8

9

10

IC1.C

&

BF245A

024117 - 11

12/2002

Elektor Electronics

33

855731330.051.png

855731330.062.png

855731330.073.png

855731330.084.png

855731330.001.png

855731330.002.png

855731330.003.png

855731330.004.png

855731330.005.png

855731330.006.png

855731330.007.png

855731330.008.png

855731330.009.png

855731330.010.png

855731330.011.png

855731330.012.png

855731330.013.png

855731330.014.png

855731330.015.png

855731330.016.png

855731330.017.png

855731330.018.png

855731330.019.png

855731330.020.png

855731330.021.png

855731330.022.png

855731330.023.png

855731330.024.png

855731330.025.png

855731330.026.png

855731330.027.png

855731330.028.png

855731330.029.png

855731330.030.png

855731330.031.png

855731330.032.png

855731330.033.png

855731330.034.png

855731330.035.png

855731330.036.png

855731330.037.png

855731330.038.png

855731330.039.png

855731330.040.png

855731330.041.png

855731330.042.png

855731330.043.png

855731330.044.png

855731330.045.png

855731330.046.png

855731330.047.png

855731330.048.png

855731330.049.png

855731330.050.png

855731330.052.png

855731330.053.png

855731330.054.png

855731330.055.png

855731330.056.png

855731330.057.png

855731330.058.png

855731330.059.png

855731330.060.png

855731330.061.png

855731330.063.png

855731330.064.png

855731330.065.png

855731330.066.png

855731330.067.png

855731330.068.png

855731330.069.png

855731330.070.png

855731330.071.png

855731330.072.png

855731330.074.png

855731330.075.png

855731330.076.png

855731330.077.png

855731330.078.png

855731330.079.png

855731330.080.png

855731330.081.png

855731330.082.png

855731330.083.png

855731330.085.png

855731330.086.png

855731330.087.png

855731330.088.png

855731330.089.png

855731330.090.png

855731330.091.png

855731330.092.png

855731330.093.png

855731330.094.png

Plik z chomika:

Inne pliki z tego folderu:

bge.jpg (23 KB)
detail1.htm (4 KB)
detail2.htm (4 KB)
e02a016.pdf (1746 KB)
detail3.htm (5 KB)

Inne foldery tego chomika:

Zgłoś jeśli naruszono regulamin