|
Many thing
in our daily need that can be easily by implement a simple applied technology.
So our life become easy and comfort. We can make anything work automatic, or
work without our intervention so if we forget to run it, or to turn off it, they
will be done by their shelf.
By a simple
applied technology, such as electronics, we can solve many simple problem as
mentioned above. With the small dimension of electronic component and small
power too, we can realize our need, such as automatic lamp, remote controller,
water tank level controller.
Beside all
that mention above, we can make many device that valuable to our need, such as
decorative lamp, amplifier, detector etc. The simple applied electronic circuits
are divided in to two groups, analog and digital circuitry.
Analog
electronic circuits are those in which signals may vary continuously with time
to correspond to the information being represented. Electronic equipment like
voltage amplifiers, power amplifiers, tuning circuits, radios, and televisions
are largely analog (with the exception of their control sections, which may be
digital, especially in modern units).
In digital
electronic circuits, electric signals take on discrete values, which are not
dependent upon time, to represent logical and numeric values. These values
represent the information that is being processed. The transistor is one of the
primary components used in discrete circuits, and combinations of these can be
used to create logic gates. These logic gates may then be used in combination to
create a desired output from an input. In this page you can find one of the
circuit.
Water Detector Using
Transistor
Resistansi air dapat digunakan sebagai pemberi tegangan
ke basis transistor. Dengan kondisi seperti itu maka akan kita dapatkan
sebuah sensor pendeteksi air. Resistansi air dideteksi menggunakan sepasang
ujung probe berbahan logam dengan panjang sekitar 2 cm serta diletakan
secara sejajar sejauh 1 cm. Dengan kondisi seperti ini resistansi air tanah
adalah dalam orde kilo ohm. Dengan rangkaian seperti pada Gambar 1, maka
level air dalam suatu tangki akan terdeteksi dengan menyalanya led.

Gambar 1. Rangkaian Detektor Air
Untuk membuat level air yang terdeteksi adalah teliti,
maka rangkaian probe dan transistor diperbanyak. Untuk mempermudah dalam
pembuatan, maka probe ditusukan pada pipa paralon, kemudian probe disambung
dengan kabel yang panjang sehingga dapat dimonitor dari bawah.
Rangkaian probe ini harus dirawat secara periodik karena
jika sudah dipakai agak lama maka probe akan tertutup oleh partikel lumpur
yang akan mengurangi kepekaan.

|