What components are on those schematics?

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Hello,

I need some help identifying the components over those 2 schematics. I allready identify them,but I do not know if I am missing something or not.

Thanks.

Code:
1X Transistor TN2905A 1x capacitor 1.0 mF
5x 470 ohms resistor
25 LED (LUMILED)
1x fotoresistor (LDR)
12 V power supply




V1 = 12V
L1 = 10uH
R1 = 100Ohms
C1 = 100nF
R2 = 100K
R3 = 3K
Q1 = BC547
R4 = 200 Ohms
R5 = 100 Ohms
IC1= LM339
R6 = 10 Ohms
LED = Blue LED


Mobile-Phone-Detector-Circuit-Diagram.jpg Auto-Night-Lamp-Using-LED-Circuit.jpg
 

K8MHZ

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Michigan. It's a beautiful peninsula, I've looked
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Here is a link to the original article:

http://www.electronicshub.org/cell-phone-detector-circuit/

From that article, D1 is a Schottky diode BAT 54.

This kind of conflicts with the parts list, though:

This is achieved by selecting a resistor of 200 Ohms and a potentiometer of 330 Ohms.

I didn't see any of this in the article:

1X Transistor TN2905A 1x capacitor 1.0 mF
5x 470 ohms resistor
25 LED (LUMILED)
1x fotoresistor (LDR)
12 V power supply
 

GoldDigger

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Ok,so it is a variable resistor. A potentiometer?
Technically speaking (and that is often important to get the right results) a variable resistor is a two terminal device and you can change the resistance between those two terminals by turning a shaft or moving a slider.
A potentiometer is a three terminal device where two terminals are connected to the ends of the resistance element and the third terminal can be moved smoothly from one end of the resistance element to the other.
By adding a jumper wire you can convert a potentiometer to use as a variable resistor, but there is no way to convert in the other direction.

In the circuit in question a voltage is applied between the top of R5 and signal ground. The center terminal (arm) of the potentiometer feeds a variable fraction of that voltage into the IC op amp input.
 

K8MHZ

Senior Member
Location
Michigan. It's a beautiful peninsula, I've looked
Occupation
Electrician
Technically speaking (and that is often important to get the right results) a variable resistor is a two terminal device and you can change the resistance between those two terminals by turning a shaft or moving a slider.
A potentiometer is a three terminal device where two terminals are connected to the ends of the resistance element and the third terminal can be moved smoothly from one end of the resistance element to the other.
By adding a jumper wire you can convert a potentiometer to use as a variable resistor, but there is no way to convert in the other direction.

In the circuit in question a voltage is applied between the top of R5 and signal ground. The center terminal (arm) of the potentiometer feeds a variable fraction of that voltage into the IC op amp input.

Good explanation. Also, if I may add, a two terminal variable resistor is also called a rheostat. Here is the symbol.

RheostatSymbol.png
 

Jraef

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Electrical Engineer
Good explanation. Also, if I may add, a two terminal variable resistor is also called a rheostat. Here is the symbol.

RheostatSymbol.png

LOL I was going to say rheostat, but the last time I used that in a sentence, one of the youngsters I was working with looked like a deer in the headlights...
 
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