Hello,

I can't seem to see why the R7 resistor is not showing a current. I've redone the circuit three times and I'm still not getting any result. Is it something to do with the program? I've attached the LTspice file, the circuit diagram, and my simulation results. If anyone can help that would be great. Thanks.

I've replaced the LDR and Buzzer with 1000 ohm resistors.

 

Hello,

I can't seem to see why the R7 resistor is not showing a current. I've redone the circuit three times and I'm still not getting any result. Is it something to do with the program? I've attached the LTspice file, the circuit diagram, and my simulation results. If anyone can help that would be great. Thanks.

I've replaced the LDR and Buzzer with 1000 ohm resistors.

I opened your .asc file but it looks very different than the image. Did you attach the right file?

 

I opened your .asc file but it looks very different than the image. Did you attach the right file?

Sorry yes, it is the correct file. It does not seem that way because of the way the wires are configured. I tried to keep it as simple as possible. The LTSpice 555 timer is not configured the same as the 555 timer on the image.

 

Sorry yes, it is the correct file. It does not seem that way because of the way the wires are configured. I tried to keep it as simple as possible. The LTSpice 555 timer is not configured the same as the 555 timer on the image.

I was referring to your screen capture of the LTspice simulation. That's not what I see when I open your file.

 

I was referring to your screen capture of the LTspice simulation. That's not what I see when I open your file.

View attachment 201909

oh, wow. That is not what I get when I open my file. I've opened it on my other computer and I'm still not getting that. The circuit on my screen capture is the one I'm getting.

 

oh, wow. That is not what I get when I open my file. I've opened it on my other computer and I'm still not getting that. The circuit on my screen capture is the one I'm getting.

Odd. It's not unusual to encounter trouble with project portability but this one is odd. LTspice would normally throw up alerts if there was a problem but I didn't get anything. We'll see what other folks see.

 

You have D1 cathode, Trig, Thr, Rst and C1 all shorted to the +ve rail.

 

You have D1 cathode, Trig, Thr, Rst and C1 all shorted to the +ve rail.

Hello,

Yes I do. I connected everything just like it was in the circuit diagram. I did not know I was not supposed to connect it that way. How do I fix this?

 

Hello,

Yes I do. I connected everything just like it was in the circuit diagram. I did not know I was not supposed to connect it that way. How do I fix this?

Look for the pink dots. That's where connections are made. Two lines intersecting without a pink dot are NOT connected.

 

I now see that the reset output was supposed to be connected by itself to the positive rail, but all resistors are still showing no current (or voltage)

@wayneh I'm not sure what pink dots you are referring too. I don't think I've seen those on this program.

 

Yes I do. I connected everything just like it was in the circuit diagram. I did not know I was not supposed to connect it that way. How do I fix this?

D1 has no value and shorted to the positive rail

 

Facepalm moment - I was looking at the wrong file. Your's is fine. I've made a couple changes. It's still not working but is closer.

The pink dots are in the schematic picture you attached (not the sim).

 

D1 has no value and shorted to the positive rail

Thank you. I put a 0.7 value for the diode.

 

Facepalm moment - I was looking at the wrong file. Your's is fine. I've made a couple changes. It's still not working but is closer.

The pink dots are in the schematic picture you attached (not the sim).

View attachment 201916

Thank you very much. I really appreciate you trying! I put a value of 0.7 for the diode. I'm still trying to figure out why there's no current at the 100 and 1000 resistors. Still haven't reached a conclusion.

 

Here is an altered version. The first 555 is in a typical configuration and will at least run.

 

I just wanted to attach this image just to show that the circuit diagram does result in a completed circuit (The red LED is on, next to the buzzer at the top of the breadboard). It just seems that this simulation on LTSpice doesn't want to work.