I am still stuck on reading and understanding schematics. Can someone please point me in the direction on where or how I can learn what the connections are doing. I am attaching a schematic of a circuit that I have not been able to complete for months now. my first problem is C4 I know that one end goes to ground but where does the other end go? is it to R3, to 5v/12v, or does it go to pin 4 of the 555 timer. Also C1 I know that one end goes to ground but the other end does it go to VR1 or to pin 6. And C2 again ground on one side but on the other is it R1 or to pin 8. I am very clear on the single connections like pin 1 go ground, and pin 5 go ground through a .1uf capacitor. but lost when they have multiple connections. All I have is this web site, some books and google, but I can't find the answer to this problem of mine. thank you in advance to anyone who can point me in the right direction.

 

The black lines are connections, so C4 goes to R3, 5V/12v and to pin 4 and pin 8 of both 555s, plus C6, R1, the speaker, D1 and C2.

 

The black lines are connections, so C4 goes to R3, 5V/12v and to pin 4 and pin 8 of both 555s, plus C6, R1, the speaker, D1 and C2.

Is it possible to make all those connections on a breadboard?

 

Have you looked at http://www.williamson-labs.com/pdf/555AN.pdf

Have you reviewed this instruction on how to read schematics?

Yes you can build that circuit on a breadboard.

 

Have you looked at http://www.williamson-labs.com/pdf/555AN.pdf

Have you reviewed this instruction on how to read schematics?

Yes you can build that circuit on a breadboard.

Thanks for the reply, I will check out the links now.

 

Thanks for the reply, I will check out the links now.

Have you looked at http://www.williamson-labs.com/pdf/555AN.pdf

Have you reviewed this instruction on how to read schematics?

Yes you can build that circuit on a breadboard.

I looked it over and there is some really good info, but I still can't seem to find the specific explanation of how the multiple connections work.

 

Is it possible to make all those connections on a breadboard?

It's a 2 dimensional drawing representing a 3D object, so yes you can build it for real in 3 dimensions. The spots where wires cross are pretty much the only spots where you need the 3rd dimension.

My breadboard allows 6-8 (I forget which) wires at each node. If you need more, you just hop to another node.

 

Here is a breadboard setup ... I included the schematic and the breadboard. Can you see how the "multiple" connections are accomplished?

 

Here is a breadboard setup ... I included the schematic and the breadboard. Can you see how the "multiple" connections are accomplished?

Very helpful, this is exactly what I am looking for. Do you know where I can find more examples like this?

 

No I don't.

 

Do you know where I can find more examples like this?

Try here

 

Here is a breadboard setup ... I included the schematic and the breadboard. Can you see how the "multiple" connections are accomplished?

Joe, this is very helpful, do you know where I can get to look at more examples. I don't know why none of the books or web sites explain the connections. Either I over thought, or added 2+2 and came up with 5. But this has been giving me trouble for well over a year now. Thanks to your post I think I am on my way to figuring this out. Thank you again.

 

You have showed us your schematic. You have not shown us your attempt to breadboard it. If you don't have anything on your breadboard, insert the chips and connect just the power layout to the chips, every connection directly connected to positive and ground. Then post a picture of your breadboard.

This way we can see something other than words on this screen.

Remember, I only want to see the power connections to the chips.

I don't like troubleshooting a breadboard that looks like this, and there have been worse than this:

So do the job neatly.

 

You have showed us your schematic. You have not shown us your attempt to breadboard it. If you don't have anything on your breadboard, insert the chips and connect just the power layout to the chips, every connection directly connected to positive and ground. Then post a picture of your breadboard.

This way we can see something other than words on this screen.

Remember, I only want to see the power connections to the chips.

I don't like troubleshooting a breadboard that looks like this, and there have been worse than this:

So do the job neatly.

Joe: this is my latest failed attempt, I am attaching the pictures. Let me know if you want any other info.

 

What test equipment do you have?

On edit:

If you have a DMM, check the voltages to ground on every pin of the chips and the transistor.

Record and post them.

 

What test equipment do you have?

On edit:

If you have a DMM, check the voltages to ground on every pin of the chips and the transistor.

Record and post them.

IC 1 farthest from transistor Pin1=0v, Pin2=.160mv, Pin3=5.9v, Pin4=7.0v, Pin5=4.6v, Pin6=.160mv, Pin7=.156mv Pin8=7.03v.

IC2 closest to transistor Pin1=0, Pin2=.160mv, Pin3=5.7v, Pin4=7.0v, Pin5=5.02v, Pin6=.158mv, Pin7=.157mv, Pin8=7.03v.

Transistor TIP31 Base jumps from .005 to 000mv, collector .003, Emitter .000

 

You need to look how you have that transistor connected or that transistor might be defective.

Post a clear picture of just the transistor area.

 

IC 1 farthest from transistor Pin1=0v, Pin2=.160mv, Pin3=5.9v, Pin4=7.0v, Pin5=4.6v, Pin6=.160mv, Pin7=.156mv Pin8=7.03v.

IC2 closest to transistor Pin1=0, Pin2=.160mv, Pin3=5.7v, Pin4=7.0v, Pin5=5.02v, Pin6=.158mv, Pin7=.157mv, Pin8=7.03v.

Transistor TIP31 Base jumps from .005 to 000mv, collector .003, Emitter .000

Here are the pictures of the Transistor, also I took a picture of the readings from a little tester.

 

Here are the pictures of the Transistor, also I took a picture of the readings from a little tester.

I am also not sure what C4 connects to, I know that one end goes to ground, but I am not sure where the other ends go.

 

C4 connects between the +V supply and ground. Those lines represent a wire ... and the dots represent a connection.

If you changed any connections, remeasure the transistor connections to ground.

I don't like the fact that the Q1 base is too low, it should be closer to 0.5 to 0.7 volts. I don't like the fact that Q1 collector is zero. It should be higher, possible about half the supply voltage or more depending on how your DMM samples the signal.