Inverting operational amplifier circuit won't work

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gothloli
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I'm making a simple circuit on the breadboard with a 741 op amp. The feedback resistor is 150 kohms, and the input resistor is 100 kilo ohms, means the gain is 1.5. The input voltage is about 5.33. The power supply is ±18 V. For some reason the output voltage is 0.98 V instead of the amplified voltage. Also when I try the LF356N it doesn't show any output voltage at all.

Below is a picture of my circuit
 
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I can only see three batteries. How are you getting +/- 18 volts?

How are you getting 5.33 volts input? I can't see any divider resistors. I would make this 1 volt for test purposes anyway.

The red wire on the top battery doesn't seem to go anywhere.

Are you using this circuit?

Schematic of an inverting operational amplifier: input Vin feeds through resistor Rin to the inverting (minus) input, feedback resistor Rf connects from the output Vout back to that node, and the non-inverting (plus) input is grounded.
 
yah I'm using that circuit.
But the battery I used for the input signal is 5.33 because I burnt it out, because I don't have 1.5 volt batteries around
 
I don't see any connection between the midpoint of the two supply batteries, pin 3 and your input's "zero" side. Those three things need to be connected together.
As has been pointed out, your supply only seems to be +/-9V. That should be just about enough though.
 
gothloli said:
yah I'm using that circuit.
But the battery I used for the input signal is 5.33 because I burnt it out, because I don't have 1.5 volt batteries around

No, you're not using that circuit (inverting amp). You're using this circuit. Its a non-inverting amplifier. Gain = 1 + R2/R1 ( = 2.5 in your case)

Circuit schematic of a non-inverting op-amp amplifier: Input goes to the + terminal, the - terminal connects to R1 to 0V and to feedback resistor R2 back to the output labelled Opt.


Also give the circuit a common ground by connecting the middle of +-18V battery to the negative terminal of your input. (i.e. at the other end of the resistor you took out from pin 2)
 
gothloli said:
I'm making a simple circuit on the breadboard with a 741 op amp. The feedback resistor is 150 kohms, and the input resistor is 100 kilo ohms, means the gain is 1.5. The input voltage is about 5.33. The power supply is ±18 V. For some reason the output voltage is 0.98 V instead of the amplified voltage. Also when I try the LF356N it doesn't show any output voltage at all.

Below is a picture of my circuit

I look at you breadboard. The top battery is supposed to be the input voltage. The black wire is connected to the 100K which connect to pin 2 as input. Problem like Vk6kro said, the red wire of the battery is not connected to the breadboard! If I see you picture correctly, you are not going to get anything meaningful out of this. I can't see where the clip on the black wire goes to as your picture don't show. You need to have connection to the ground reference to establish the potential. The ground reference is the junction of the red wire of the lower battery on the left side and the black wire of the lower battery on the right side. You have no connection of the ground reference to any other points.
 
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vk6kro said:
I can only see three batteries. How are you getting +/- 18 volts?

How are you getting 5.33 volts input? I can't see any divider resistors. I would make this 1 volt for test purposes anyway.

The red wire on the top battery doesn't seem to go anywhere.

Are you using this circuit?

Circuit schematic of an inverting operational amplifier: Vin feeds through Rin to the inverting input, Rf connects from the inverting input back to Vout, and the non-inverting input is grounded.

He has only +/-9V. He used an empty clip to hold the red of the left battery to the black of the right battery.