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Can i get a replacement of this transistor ? Answered

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Hello,
i was just messing with circuits and i found this one above in the image i really want to make this but i don't have a BF494 transistor so my question is : Is it possible to replace this transistor with any other transistor if possible please name all possible replacement you know!

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steveastroukBest Answer (author)2013-06-17

Check the Ft of the BF494 (200Mhz) and match it with what you can get locally. The BT494 is a pretty damned fast little transistor, so be careful.

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samaddon (author)steveastrouk2013-06-17

Thanks for your help but tell me what Ft stands for ? (Beause i am not well known to electronics!)

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steveastrouk (author)samaddon2013-06-17

Ft stands for "transition frequency", and is a measure of the kind of frequencies you can expect the transistor to work at
Its a parameter on the datasheet for the transistor. Look for "High frequency" transistors.

The BC109 might be OK for you here.

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ajay20060 (author)2017-04-06

if i have bc 107 transistor which have different characterstic of bf494 so what change we have eo in circuit

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vikasgurlinka (author)2016-03-18

2N3904 or 2N2222 might do you but a 2N3707 is identical to a BF494.

You can get the datasheets here:

http://www.maxim4u.com/

You can get the datasheets and the parts for less than Radio Shack here:

http://ca.mouser.com/Electronic-Components/

Mouser has a great search filter that enables you to put the parameters of a component in and it will tell you all the parts that fit.

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stoobers (author)2016-02-01

This looks like an am receiver with fixed regeneration. if so you can use any npn "popcorn" transistor. Common examples include 2n2222 or 2n3904.

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EiadS (author)2015-12-30

doest tl494 replace bf494

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denmarkmediana. (author)2015-11-07

hi, what is the replacement for B1453 transistor

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samaddon (author)denmarkmediana.2015-11-08

2SC5880 from farnell will do your job. Because you need a low Ft , so i am guessing it is for some high voltage switching (60).

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farhan.ali.92351 (author)2014-08-16

Hello , i dont have a 2N2222, so is it possibloe to replace this transistor with any other transistor is possible

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user

Yes, for general purpose circuit BC 547 or BC 548 or bc 557 work pretty same !

Though you can show me the circuit i will tell you what to do!

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user

I use BC 457 AND 458 -- NPN --- virtually the same
BC transistors are quite common ---
2n2222 have slight voltage difference ---
look up in your tables ---its all there
regards---

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farhan.ali.92351 (author)2014-08-16

Hello , i dont have a 2N2222, so is it possibloe to replace this transistor with any other transistor is possible

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Josehf Murchison (author)2013-06-17

BC548, BC549, or 2N3904 should do you a good source for them is Mouser although they don’t have BF494 in stalk.

http://ca.mouser.com/search/Default.aspx

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iceng (author)2013-06-17

The physical placement of the RF ( Radio Frequency ) components is CRITICAL
So is the length  of the antenna and the diameter of the four turns..

If you have a pic of this working Follow it exactly.

A

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