Rangkaian Pendeteksi kadar Air dalam Pot Tanaman

Rangkaian Tester kadar air pot tanaman ini sangat berguna sekali bagi yang suka menanam tanaman dalam pot apakah masih cukup kadar airnya atau kurang. Sehingga anda tidak usah kotor kotoran untuk mengetahui kadar air dalam pot. Rangkaian ini sangat sederhana sekali karena hanya membutuhkan beberapa komponen saja. Untuk Probe gunakan bahan logam seperti paku atau kawat.

Cara kerja dan pengetesan:
Untuk mencobanya anda siapkan pot yang berisi tanah kemudian berilah air secukupnya kemudian masukkan/tusukkan kedalam tanah di pot dan setel Potensiometer sampai menyala. Kemudian cobakan probe dimasukan ke tanah yang masih kering atau kadar airnya rendah, lampu Led seharusnya tidak menyala. Anda perlu menyesuaikan potensiometer 47k untuk mengatur tingkat di mana LED akan menyala.

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Pengukur Suara Speaker

This circuit can be used to setup their home-cinema set adjusting all the loudspeaker outputs to the same level when heard from the listening position. The circuit is very simple (though linear and precise) ac millivoltmeter, using an existing multimeter set to 50 or 100µA fsd with the probes connected to J1 and J2 to read the results.

Skema Rangkaian Pengukur Suara Speaker

List coponent

R1................................... 10K  1/4W Resistor
R2,R3............................... 22K  1/4W Resistors
R4................................... 100K  1/4W Resistor
R5................................... 100R  1/4W Resistor
C1................................... 1µF  63V Polyester or Electrolytic Capacitor
C2................................... 100µF  25V Electrolytic Capacitor
C3................................... 220µF  25V Electrolytic Capacitor
D1-D4............................... BAT46  100V 150mA Schottky-barrier Diodes
IC1................................... CA3140  Op-Amp IC
MIC................................... Miniature electret microphone (See Notes)
J1,J2................................. 4mm  Output sockets
SW1.................................. SPST  Toggle or Slider Switch
B1................................... 9V

The precision of the measure is entirely depending on the frequency response of the microphone used but, fortunately, for the main purpose of this circuit an absolutely flat response is not required. Therefore, a cheap miniature electret microphone can be used.

Note:
Please be careful and set the volume control very low, to avoid loudspeakers' damage. Switch-on the Sound Pressure Level Meter and increase the volume of the amplifier in order to obtain an approximate center-scale reading. Repeat the same steps with all channels.

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Rangkaian Sound Level Meter

Skema rangkaian sound level meter

This is circuit can be used to check the sound levels.The sound pressure meter is vey useful in setting up home theater systems , if you need to test the sound pressure of each channels on different positions in the room.

The circuit is nothing but a non- inverting amplifier based on op-amp CA 3140. The sound picked by the condenser mic will be amplified by the IC1 and rectified by the bridge D1 to drive the meter M1. The deflection on the meter will be proportional to the pressure of the sound falling on the mic.The switch S1 can be used as an ON/OFF switch.

Note:

• The bridge D1 can be a 1A bridge.If 1A bridge is note available,make one using four 1N4007 diodes.
• The circuit ca be powered by using a 9V PP3 battery.

Pin IC CA3140

The IC CA3140 is integrated circuit operational amplifiers that combine the advantages of high voltage PMOS transistors with high voltage bipolar transistors on a single monolithic chip.

Features

• Very High Input Impedance (ZIN) -1.5TΩ (Typ)
• Very Low Input Current (Il) -10pA (Typ) at ±15V
• Wide Common Mode Input Voltage Range (VlCR) - Can be Swung 0.5V Below Negative Supply Voltage Rail
• Output Swing Complements Input Common Mode Range
• Directly Replaces Industry Type 741 in Most Applications
• Pb-Free Plus Anneal Available (RoHS Compliant).

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Square/Triangle/Sine-wave generator (Generator Sinyal)

A test signal generator is invaluable when making or repairing electronic equipment. Although a fully-fledged, accurate (and expensive!) sig gen is desirable, there are many occasions when a simple, non-calibrated, highly portable signal source will suffice for a quick test such as signal tracing. To that end I've designed this circuit which selectively generates square, triangle and pseudo-sine waves in three frequency ranges covering 15Hz to 2MHz.

The core of the generator is a Schmitt-trigger oscillator U1 whose frequency is determined by the setting of a 100k pot Rt and one of three switch-selectable capacitors Ct1-Ct3. These passive components should have short connecting wires to minimise spurious signal pick-up. Unused Schmitt gate inputs in the CD4093 or CD40106 IC should be grounded.
The U1 gate output is a square wave, and the voltage on the Ct capacitor is a triangular wave. The triangular wave is shaped by diodes D1, D2 into a reasonable approximation of a sine wave. Any one of these waves is switch-selectable.
The selected wave may be used as is, to feed a high-impedance load, but here it is passed to an optional buffer amplifier with a gain of 3. The amplifier comprises an LT1007 op-amp. Other op-amps would be suitable provided they have an adequate gain-bandwidth product. Capacitors C3 and C4 aid amplifier stability. C4 should be wired close to the op-amp supply pins. Resistors R2 and R3 provide a synthesised ground reference (half the supply voltage) for the op-amp. R4 and R5 set the op-amp gain. The op-amp output is AC-coupled to a 10k pot for output-level control.
The op-amp frequency response is practically flat up to ~ 20kHz and then tails off, but the output directly from U1 stays flattish up to ~ 200kHz. There is still a very usable output up to 2MHz.
The sig gen can be run from a PP3 battery and housed in a small box. Current consumption is about 8mA.

Footnote: Feedback welcome on circuit performance and suggested improvements.

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Sound Level Meter

This is circuit can be used to check the sound levels.The sound pressure meter is vey useful in setting up home theater systems , if you need to test the sound pressure of each channels on different positions in the room.

The circuit is nothing but a non- inverting amplifier based on op-amp CA 3140. The sound picked by the condenser mic will be amplified by the IC1 and rectified by the bridge D1 to drive the meter M1. The deflection on the meter will be proportional to the pressure of the sound falling on the mic.The switch S1 can be used as an ON/OFF switch.

Skema rangkaian sound level meter

Note:

• The bridge D1 can be a 1A bridge.If 1A bridge is note available,make one using four 1N4007 diodes.
• The circuit ca be powered by using a 9V PP3 battery.

Pin IC CA3140

The IC CA3140 is integrated circuit operational amplifiers that combine the advantages of high voltage PMOS transistors with high voltage bipolar transistors on a single monolithic chip.

Features

• Very High Input Impedance (ZIN) -1.5TΩ (Typ)
• Very Low Input Current (Il) -10pA (Typ) at ±15V
• Wide Common Mode Input Voltage Range (VlCR) - Can be Swung 0.5V Below Negative Supply Voltage Rail
• Output Swing Complements Input Common Mode Range
• Directly Replaces Industry Type 741 in Most Applications
• Pb-Free Plus Anneal Available (RoHS Compliant).

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Silicon Transistor Tester

Prototype Alat Uji Transistor

Skema Rangkaian Alat Uji Transistor Silicon

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