Hi, how do you attach the 10k to the 9V supply rail in my diagram. Can just label it

Vout ← (1K~10K) → +9V

 

Vout ← (1K~10K) → +9V

no signal

 

Try to add a 33K from (+)input to +9V.

 

n

Try to add a 33K from (+)input to +9V.

no signal. If anyone has this LM 319, worth a try on this

 

Try to make a test circuit like this.

 

Th

Try to make a test circuit like this.

I made the circuit and the LED lights up but does not blink and no square wave signal on my scope

 

That test circuit only tests that the comparator is working. You won't see it blinking. But it's acting like a "Sink" for the LED, that is, it's grounding the LED to turn it on.

 

hi Mrss
Try this Note pin #3 to 0V
E

 

Th

I made the circuit and the LED lights up but does not blink and no square wave signal on my scope

The circuit just to do the test, does the comparator is working fine or not, did you adjust the VR1 to test the output going to Hi and Low?

 

From my reference manual it seems that the LM319 does not need a negative supply, but that the Vee pin can be tied to the positive supply common. As the Vee- pin is the reference for the inputs that may be the problem. So both "Gnd" pins, along with the Vee, need to tie to the V+ supply common (negative) side. My manual shows that, and claims that it can work down to +5 volts supply.

 

Does the LM319 package you are using have a separate GND pin as your package pinout shows?

 

hi Mrss
Try this Note pin #3 to 0V
E
View attachment 255596

Hi, I have tried your suggestion and all connections are secured with all resistance values being measured using multimeter and its correct. I am still not getting any good square wave output. Feel dissapointed

 

Does the LM319 package you are using have a separate GND pin?

It is LM 319N. Do you have this package, can just plug it in on breadboard give it a try

 

View attachment 254944
This (above) is the circuit I and others used. It is similar but this one uses and LC tank (C1 and Lx) connected to the non-inverting input of the LM319.

The LM319 is good for 36 volts so ±10 volts should be fine. If you use a split supply you will not need the resistor from (in the schematic above) +5V to the + input.

Hi sir, Merry Christmas
I have bought the LM 319N actually and I tested it but does not really work and I have asked it in another forum here

 

Hi, I have tried your suggestion and all connections are secured with all resistance values being measured using multimeter and its correct. I am still not getting any good square wave output. Feel dissapointed

What do you get from output? How do you test it?

 

What do you get from output? How do you test it?

Using my oscillioscope, I get 0V and my scope is working fine. Is anyone able to spot mistake on my breadboard connections?

 

On your last photo I see the negative 9 volts connected to pin 5 not pin 6.

 

On your last photo I see the negative 9 volts connected to pin 5 not pin 6.

Hi, I made the correction. Still no signal at output lol

 

What is the value of the cap installed?

 

What is the value of the cap installed?

I put it as 1uF instead of 0.01uF because lower frequency does not matter and even if I used 0.01uF, it still giving me no output. Weird comparator this one