Problem with PUT 2N6027

[ramin110]

Is 2n6027 has two type of PNP And NPN ?

 

[davenn]

hi ramin
welcome to the forums

Google solves many problems ... the 2N6027 is neither NPN or PNP as it isnt a standard bipolar transistor .... its a Programmable Unijunction Transistor --- PUT
a PUT is a diode with a gate connection so you have Anode - Gate - Cathode

cheers
Dave

 

[ramin110]

thanks for your answer, i am new in electronic and reading electronic for beginners but in page 85 from book Make Electronics this project not working i'm doing exactly what the book says. please help

hi ramin
welcome to the forums

Google solves many problems ... the 2N6027 is neither NPN or PNP as it isnt a standard bipolar transistor .... its a Programmable Unijunction Transistor --- PUT
a PUT is a diode with a gate connection so you have Anode - Gate - Cathode

cheers
Dave

 

[(*steve*)]

You need to tell us exactly what it is doing.

Also, do you have a multimeter?

Also, can you post a picture of your breadboard so we can check for wiring errors.

 

[ramin110]

first of all sorry for bad picture, so i drew lines maybe you can figure out what's going on here. if still you can't understand i can borrow camera and take a picture.
the concept of project is blinking led. i searched from internet and got nothing
my full PUT name is : 2N6027 901
thanks

Voltage : 12V DC

You need to tell us exactly what it is doing.

Also, do you have a multimeter?

Also, can you post a picture of your breadboard so we can check for wiring errors.

 

[(*steve*)]

No, I need an image clear enough that I can read the bands on the resistors and see if the LED is around the right way.

You still haven't told us what it's doing or whether you have a multimeter.

 

[ramin110]

here is the pictures of my wonderful project
and yes i have a multimeter and it's must blinking (flashing led)

No, I need an image clear enough that I can read the bands on the resistors and see if the LED is around the right way.

You still haven't told us what it's doing or whether you have a multimeter.

 

[(*steve*)]

That's an excellent photo!

I need to make a bit of a guess that the resistor that is partially obscured is red-violet-orange.

Are you telling us that the LED is not flashing (it will be a brief flash with a longer delay between flashes)?

You could connect your multimeter on a low voltage range across the 2.2uF capacitor. You should see the voltage changing. If your multimeter is fast enough (or the flashing slow enough) you should see it slowly rise then rapidly fall (and repeat...)

 

[ramin110]

i changed my PUT with another one and it's working now!
now my question is :
is first PUT is burned? because i bought all of them from same shop and all of them are new but they have different name. That one is not working is named with 2N6027 901 and the one is working is named with 2N2067 610. so what's the problem?

That's an excellent photo!

I need to make a bit of a guess that the resistor that is partially obscured is red-violet-orange.

Are you telling us that the LED is not flashing (it will be a brief flash with a longer delay between flashes)?

You could connect your multimeter on a low voltage range across the 2.2uF capacitor. You should see the voltage changing. If your multimeter is fast enough (or the flashing slow enough) you should see it slowly rise then rapidly fall (and repeat...)

 

[ramin110]

i figure out something!!
i bought 5 PUT . 2 of them named 2N2067 910 and these two not working and another 3 named 2N2067 610 and working probably! so what is the difference between these two models?

 

[(*steve*)]

You have duplicated your post, but you've typed a different story each time.

One thing I'd probably recognize is that a 2N2027 is an SCR in a TO-94 package, not a PUT in a TO-92 package.

Can you check again?

 

[ramin110]

2 PUT with name 2N6027 901 not working and other 3 with name 2N6027 610 working.
what is the differences between them ???

You have duplicated your post, but you've typed a different story each time.

One thing I'd probably recognize is that a 2N2027 is an SCR in a TO-94 package, not a PUT in a TO-92 package.

Can you check again?

 

[(*steve*)]

It's probably a date code. That essentially means there is no difference.

Perhaps you destroyed them?

 

[ramin110]

maybe it's date code, but i bought 2 another PUT with code 2N6027 901 and they don't worked either helpppppppppppp please it's gonna be a mystery

It's probably a date code. That essentially means there is no difference.

Perhaps you destroyed them?

 

[Riya208]

i changed my PUT with another one and it's working now!
now my question is :
is first PUT is burned? because i bought all of them from same shop and all of them are new but they have different name. That one is not working is named with 2N6027 901 and the one is working is named with 2N2067 610. so what's the problem?

Hi ramin110,
I am new here. I am facing same problem what you have faced. I am doing exactly what it is in the book, but I am not getting output. I am using 2N6027 110 since that is the only one available in the store. I've noticed one thing. When I connect the circuit other way round i.e cathode pin to resistor and capacitor combination and anode to LED, then LED glows (doesn't flash though). Why is that so? It's like same circuit but just pins interchanged. I did this accidentally at first so I thought I burnt PUT, then I took another one and this time I inserted properly but didn't work. Do you think it's PUT fault just like yours?

 

[Riya208]

That's an excellent photo!

I need to make a bit of a guess that the resistor that is partially obscured is red-violet-orange.

Are you telling us that the LED is not flashing (it will be a brief flash with a longer delay between flashes)?

You could connect your multimeter on a low voltage range across the 2.2uF capacitor. You should see the voltage changing. If your multimeter is fast enough (or the flashing slow enough) you should see it slowly rise then rapidly fall (and repeat...)

Hi steve,
I am new here. I am facing same problem what ramin110 had faced. I am doing exactly what it is in the book, but I am not getting output. I am using 2N6027 110 since that is the only one available in the store. I've noticed one thing. When I connect the circuit other way round i.e cathode pin to resistor and capacitor combination and anode to LED, then LED glows (doesn't flash though). Why is that so? It's like same circuit but just pins interchanged. I did this accidentally at first so I thought I burnt PUT, then I took another one and this time I inserted properly but didn't work. Do you think it's PUT fault just like ramin110?

 

[(*steve*)]

Can you confirm exactly what the device markings are. Also post an image of your construction.

 

[Nrublim]

Were you able to figure out what the issue was? I'm going through the Make Electronics (1st edition) now myself and ran into the same problem. I built the circuit just like the book shows. When I apply the power source the LED comes on steady and does not blink.

I'm using the Radio Shack kit. The PUT is labeled 2N6027 E27. I've measured the resistance of each of the resistors and they match the layout in the book. I've measured the voltage across the capacitor and it holds at a steady 2.77V.

[update]: Okay, now I feel like a dork. R1 was supposed to be 470k and I missed the k so I had a 470 Ohm resistor in it's place. Now that I put the correct resistor in the circuit is working properly.

 

[ramin110]

Hi steve,
I am new here. I am facing same problem what ramin110 had faced. I am doing exactly what it is in the book, but I am not getting output. I am using 2N6027 110 since that is the only one available in the store. I've noticed one thing. When I connect the circuit other way round i.e cathode pin to resistor and capacitor combination and anode to LED, then LED glows (doesn't flash though). Why is that so? It's like same circuit but just pins interchanged. I did this accidentally at first so I thought I burnt PUT, then I took another one and this time I inserted properly but didn't work. Do you think it's PUT fault just like ramin110?

after sometimes I contacted with the supplier where I bought them and they admit that some of there PUTs was faulty and after that I just try to buy my parts from creditable shops.
just keep in mind after learning electronic nearly 3 years, I thing every possible thing must be consider as a problem.
keep learning and learning and have a fun with the world of atoms.