Newbie - transistor n3906 to breadboard ?

[trope]

I am trying to build a circuit with a N3906 transistor on a breadboard, partial diagram attached.

I am wondering , could someone show me how to do this on a breadboard? I don't know where the base, collector, and emitter go.

Can someone point me in the right direction with an actual example based upon my diagram?

Thanks so much!

J Trope!

 

[shrtrnd]

Google the data sheet on 2N3906.
It's a very common transistor.

 

[trope]

I have, I am just unsure on how to use it on a breadboard.

Does the entire transistor (all 3 connections) reside on one "row" ? Or do I need to seperate the base, coll, and emitter so they are not on same row?

 

[davelectronic]

They must be on separate rail/tracks for correct operation, if not your short the transistor, a no no. Dave.

 

[trope]

any way i can talk you into an example breadboard pic based upon my diagram?

 

[TBennettcc]

See the following link to learn how a breadboard is laid out. Post if you have further questions.

http://www.kpsec.freeuk.com/breadb.htm

 

[trope]

Tim,

Awesome link! That article helped alot.

It's become apparent to me that a breadboard layout is much different than following a tutorial schematic you find online. Thus, the reason for my confusion - but the good news is , it's starting to make sense.

There is no one correct answer on how to connect this transistor to a breadboard ( if I am understanding things right ). You need to make sure the base , which is in the middle of the flat side of the transistor , is attached to the battery , and from there take your collector and emitter on their respective routes????? Am I close??? LOL

Thanks

JT

 

[davenn]

your cct (very incomplete) shows the emitter going direct to the battery, not the base

Dave

 

[trope]

Hey Davenn, here is the complete circuit:

http://science.discovery.com/brink/kip-kay/images/plans.jpg

am I mistaken , still ?

Thanks!

 

[jackorocko]

Hey Davenn, here is the complete circuit:

http://science.discovery.com/brink/kip-kay/images/plans.jpg

am I mistaken , still ?

Thanks!

Dave is correct, the emitter is tied to the battery on both transistors. The emitter is the one with the arrow attached to it.

Q2 emitter is tied to the + side of the battery and Q1 emitter is tied to the - side of the battery.

 

[trope]

Thanks Jackorocko, Dave.

Slowly this first circuit I am building is starting to make sense.

 

[trope]

OK.....

Guys please bare with me. I will be surprised if I get any replies to this thread.

This particular project is what I have decided to make.

I HAVE read the Dummy book, I have followed the links provided in this thread, and also done many, MANY hours of research myself.

Although this little "lie detector" circuit (http://kipkay.com/wp-content/uploads/2010/03/Build-a-Lie-Detector.pdf ) appears to be simple, I have many questions even after all my studying.

Again, I am not taking away anything from this forum, but as a seasoned computer program, I realize how easy it is to overlook newbie questions. I am even guilty of doing that myself in the past.

That being said.... if you are still with me, please watch this short video from KIPKAY:

Now my NEWBIE questions:

1. I read there are two ways of drawing schematics, conventional and (some other term I don't remember) - How am I to know which way the current is flowing when trying to follow this video tutorial? He never says.

2. I have read the article on Galvanic Skin Response ( http://www.extremenxt.com/gsr.htm ) and understand somewhat how the finger pads work. However....

3. Why couldn't you hook up the finger pads directly to a multimeter to detect responses?

4. What function does the Capacitor do in this circuit?

5. How did he figure out what capacitor to use?

BASICALLY.....

Can someone walk me through this circuit? Even in high level terms.

If you missed my introduction in the New User Forum, I am a programmer. I am sure many of you , like myself, decide to tackle projects / programs that will challenge you, rather than the obligatory "hello world" in the programming field, or apparently the "LED Light" in the electronics world.

Lastly, I am mostly confused as to the current flow ( as I know this is a parallel circuit ) , and WHY he used the components he did, and WHY and WHEN the finger pads come into play.

I am determined to not only make this, but understand how and why it works ( or maybe it doesn't ! )

Thanks so much. Any replies will be very helpful. Just no more Google links, trust me, I have read the books, I have bought the Radio Shack kits, I have bought the breadboards, I have watched the YouTube Videos, etc. It's APPARENT I AM MISSING SOMETHING FUNDAMENTAL. I am missing the "don't forget to end your javascript statements with a semi-colon! A mistake that will cost you many minutes/hours of debugging"

Can anyone help me over this hump? If not, I understand.

Thank you all.

Regards,

John T.

 

[jackorocko]

1. When you are analyzing circuits which ever way you start is the way you should end. With that said, it doesn't matter which way you decide to start.

3. You could do this, you should see the resistance fall as the skin becomes clammy 'when you lie'. But how much the resistance changes maybe very minute and the reason for the transistors in the circuit to amplify the small changes.

 

[trope]

Thanks for the reply jackorocko, it's becoming apparent you are very patient with us new guys.

I really hope you subscribed to this thread, as I am so determined to build this. I have already purchased all the parts ( see pic, lol - the reason I posted this was to show my sincerity in this project ). Each one of those bins contains transistors, capacitors, wires, and other electronic things I don't even know what they do, LMAO.

Anyways, your simple comment, "transistor amplifies" signal, had me Google and find this link, http://www.satcure-focus.com/tutor/page4.htm , which I am now going to study and read until I fully understand it.

I will be back with questions if you don't mind.

Regards,

John

ps. my new parts , lol :

Uploaded with ImageShack.us

 

[trope]

UGH getting frustrated....

Ok, regarding the transistor amplification effect, in the circuit above, it's clear the emitter is attached to the battery, right?

http://www.satcure-focus.com/tutor/images/tmodel.gif

Shouldn't the power supply be the COLLECTOR ? Why in the world is the emitter connected to the voltage?

 

[(*steve*)]

It's not exactly a circuit diagram

To create this as a schematic, you would be looking at something like this.