Cookies-law

Cookies help us to bring you our services at overunity.com . If you use this website and our services you declare yourself okay with using cookies .More Infos here:
http://www.overunity.com/5553/privacy-policy/
If you do not agree with storing cookies, please leave this website now. Many thanks for your understanding.
Amazon Warehouse Deals ! Now even more Deep Discounts ! Check out these great prices on slightly used or just opened once only items.I always buy my gadgets via these great Warehouse deals ! Highly recommended ! Many thanks for supporting OverUnity.com this way.

User Menu

FireMatch

FireMatch

CCKnife

CCKnife

Poplamp

poplamp

CCTool

CCTool

LEDTVforSale

Magpi Magazine

Magpi Magazine Free Rasberry Pi Magazine

Battery Recondition

Battery Recondition

OverUnity Book

overunity principles book

Arduino

Ultracaps

YT Subscribe

movieclipsfree

movie clips free

Gravity Machines

Tesla-Ebook

Magnet Secrets

Lindemann Video

Navigation

Products

Statistics


  • *Total Posts: 485573
  • *Total Topics: 14276
  • *Online Today: 44
  • *Most Online: 103
(December 19, 2006, 11:27:19 PM)
  • *Users: 6
  • *Guests: 196
  • *Total: 202

Facebook

Author Topic: TRANSISTOR SELECTION QUESTION  (Read 1523 times)

Offline magnetman12003

  • Hero Member
  • *****
  • Posts: 652
TRANSISTOR SELECTION QUESTION
« on: May 27, 2016, 11:02:03 PM »
I am making a project that requires a single NPN transistor. Wish to power the transistor with 12 volts without using a large resistor connected to its base.

What transistor can have a ""BASE"" voltage of ""!2 volts"" applied ''DIRECTLY'' to its base without burning up the transistor?  In most cases there is some large value of resistor there.  Transistor would have to be a motor switching type.  The faster the better.   Need part numbers.

Free Energy | searching for free energy and discussing free energy


Offline citfta

  • Sr. Member
  • ****
  • Posts: 442
Re: TRANSISTOR SELECTION QUESTION
« Reply #1 on: May 28, 2016, 04:31:05 AM »
Hi magnetman12003,

I have seen several posts by you on this and other forums where you are asking questions that indicate you don't really have a good understanding about electronics.   I would like to respectfully suggest that you take the time to study some of the free online electronics classes.  If you are serious about working or experimenting in this hobby then a good understanding is a must.  You will only frustrate yourself trying to make things work when you don't understand what you are doing.

For instance to answer your own question in this thread you can go online and look for info about the different types of transistors.  I am pretty sure you will find there are NO npn transistors you can apply 12 volts to the base and not burn out the transistor.  However there are other types like Mosfets that can take 12 volts to the gate.  Do you even know why the resistor is going to the base?  And why do you think you need to remove it?

Respectfully,
Carroll


Offline magnetman12003

  • Hero Member
  • *****
  • Posts: 652
Re: TRANSISTOR SELECTION QUESTION
« Reply #2 on: May 31, 2016, 03:01:15 AM »
Hi magnetman12003,

I have seen several posts by you on this and other forums where you are asking questions that indicate you don't really have a good understanding about electronics.   I would like to respectfully suggest that you take the time to study some of the free online electronics classes.  If you are serious about working or experimenting in this hobby then a good understanding is a must.  You will only frustrate yourself trying to make things work when you don't understand what you are doing.

For instance to answer your own question in this thread you can go online and look for info about the different types of transistors.  I am pretty sure you will find there are NO npn transistors you can apply 12 volts to the base and not burn out the transistor.  However there are other types like Mosfets that can take 12 volts to the gate.  Do you even know why the resistor is going to the base?  And why do you think you need to remove it?

Respectfully,
Carroll
Do you think a FJP5554 transistor available from Mouser can be used without a resistor in the base circuit.
The VEBO is 15 volts?

Offline magnetman12003

  • Hero Member
  • *****
  • Posts: 652
Re: TRANSISTOR SELECTION QUESTION
« Reply #3 on: May 31, 2016, 05:45:49 AM »
Hi magnetman12003,

I have seen several posts by you on this and other forums where you are asking questions that indicate you don't really have a good understanding about electronics.   I would like to respectfully suggest that you take the time to study some of the free online electronics classes.  If you are serious about working or experimenting in this hobby then a good understanding is a must.  You will only frustrate yourself trying to make things work when you don't understand what you are doing.

For instance to answer your own question in this thread you can go online and look for info about the different types of transistors.  I am pretty sure you will find there are NO npn transistors you can apply 12 volts to the base and not burn out the transistor.  However there are other types like Mosfets that can take 12 volts to the gate.  Do you even know why the resistor is going to the base?  And why do you think you need to remove it?

Respectfully,
Carroll

I have already made a self sustaining setup that charges a single 12 volt battery powering it.  My problem is I don't have quite enough current to fully  charge my single 12 volt 1.2 AH battery. Thus only a 5 straight hour run time.  That's why the questions about any current robbing resistor connected to the base of the transistor.  I am not well trained in transistor selection but can put any circuit diagram together very quickly.  My hope is to find a very simple Tesla  pancake type circuit that is very efficient as far as current flow and build it in hopes I can boost the current.  With that accomplished I will have at least a self sustaining runner with the run battery being charged at the same time.


Offline pomodoro

  • Hero Member
  • *****
  • Posts: 670
Re: TRANSISTOR SELECTION QUESTION
« Reply #4 on: May 31, 2016, 10:50:44 AM »
The base resistor, uses practically no power if you make it large enough.  Look for darlington NPN  power transistors to make it even less of an issue.  MOSFETS and IGBT are best avoided as they have a large capacitance which uses up some current. A TIP122 is a popular generic one one I use, 100V, 5A (8A Peak),current gain of 1000  beware of the the built in diode, it may not suit your needs. There are plenty of others which may be better for your design I don't know what your circuit is like.

Free Energy | searching for free energy and discussing free energy

Re: TRANSISTOR SELECTION QUESTION
« Reply #4 on: May 31, 2016, 10:50:44 AM »
Sponsored links:




Offline magnetman12003

  • Hero Member
  • *****
  • Posts: 652
Re: TRANSISTOR SELECTION QUESTION
« Reply #5 on: May 31, 2016, 08:15:32 PM »
The base resistor, uses practically no power if you make it large enough.  Look for darlington NPN  power transistors to make it even less of an issue.  MOSFETS and IGBT are best avoided as they have a large capacitance which uses up some current. A TIP122 is a popular generic one one I use, 100V, 5A (8A Peak),current gain of 1000  beware of the the built in diode, it may not suit your needs. There are plenty of others which may be better for your design I don't know what your circuit is like.

Hi ,
So far my circuit is like what's in the below video. What other transistor arrangement should give me a lot more current and do away with the 5 watt power robbing resistor?  I noticed those that made this circuit complained about transistor overheating.  If I could get the second or pickup pancake to put out enough current to charge a 12 volt 1.2 AH battery I will have made a self runner using an additional charging circuit   Will post all after completed.  A small diagram would be a great help as I can put that together in a jiffy.

https://www.youtube.com/watch?v=4UmVLfFNx7U

Offline pomodoro

  • Hero Member
  • *****
  • Posts: 670
Re: TRANSISTOR SELECTION QUESTION
« Reply #6 on: June 01, 2016, 10:43:09 AM »
Looks like a blocking oscillator.  If the TIP35C has not blown up, then you can use a similar rating darlington. The 35C only has a gain of about 25.  Try a TIP150 with a gain >100 at high current. Handles 400V, =4x the TIP35C. Its a darlington without the built in protection diode, which I assume you don't want.  Use the same resistor, to check but then increase its value to the highest that works. If transistor heats up too much then its not getting enough current through the base to saturate and acts like a resistor.
I have not  built any of these so I'm just answering your generic question.

Free Energy | searching for free energy and discussing free energy

Re: TRANSISTOR SELECTION QUESTION
« Reply #6 on: June 01, 2016, 10:43:09 AM »
Sponsored links:




 

Share this topic to your favourite Social and Bookmark site

Please SHARE this topic at: