whats this drawing?

AtomSoft

Well-Known Member

• Apr 13, 2008

• #1

What is this? Some type of transistor?
**broken link removed**

 

Last edited: Apr 13, 2008

Krumlink

New Member

• Apr 13, 2008

• #2

where and what was this in?

 

AtomSoft

Well-Known Member

• Apr 13, 2008

• #3

some where and something .. private

 

RadioRon

Well-Known Member

• Apr 13, 2008

• #4

AtomSoft said:

What is this? Some type of transistor?
**broken link removed**

Click to expand...

Yes, this is the symbol for a very common type of transistor called a Junction Field Effect Transistor, or JFET.

 

Krumlink

New Member

• Apr 13, 2008

• #5

Wow thats no help.

Example: I have a dog it looks like this (pic) What is it.

We need more than that! What is it?

 

futz

Active Member

• Apr 13, 2008

• #6

Unijunction transistor.

 

AtomSoft

Well-Known Member

• Apr 13, 2008

• #7

Krumlink said:

Wow thats no help.

Example: I have a dog it looks like this (pic) What is it.

We need more than that! What is it?

Click to expand...

I guess you where wrong..

Thanks Guys!

 

Krumlink

New Member

• Apr 13, 2008

• #8

Im saying that you just posting a pic and not telling what it's from could be hard.

 

AtomSoft

Well-Known Member

• Apr 13, 2008

• #9

Darn dont have none here lol.. Is there anything you think that maybe i could use in its place?

 

Papabravo

Well-Known Member

• Apr 13, 2008

• #10

No substitute for a JFET

No, there is nothing like a JFET (or a dame for that matter). There is no substitute for it. One unique feature of the JFET is that it conducts when Vgs = 0. The drain current in this condition is called Idss. Normally you have to take Vgs negative to pinch off the channel. This voltage is called, as you might expect, the ....pinch-off voltage.

BTW the unijunction transistor would have the little arrow meeting the channel at about a 45 degree angle.

 

AtomSoft

Well-Known Member

• Apr 13, 2008

• #11

JEFT = https://en.wikipedia.org/wiki/JFET
Unijunction = https://en.wikipedia.org/wiki/Unijunction

Thanks i guess radioshack is going to see me again today! lol maybe tommorow.... to tired for some reason

 

AtomSoft

Well-Known Member

• Apr 13, 2008

• #12

Can i use a TL082:
https://www.radioshack.com/product/...p=&sr=1&origkw=JFET&kw=jfet&parentPage=search

if so i have 2 here.

 

Hero999

Banned

• Apr 13, 2008

• #13

The symbol is an n-channel JugFET.

The TL082 is an op-amp which has JugFET inputs so is no use if all you need is a JugFET.

Please post the whole schematic and we might be able to help you properly.

 

AtomSoft

Well-Known Member

• Apr 13, 2008

• #14

i actually dont have a schematic on the pc ... only drawn and no scanner... but ill do you 1 better..

http://www.runoffgroove.com/littlegem.html

Its something with the GEM MKII...well in fact the whole schematic of that is in it but with other stuff also ... The person who the schematics belong to has asked me for some stupid reason not to post it no where. Ill tell you now its nothing spectacular.. its for a friend (paranoid guy)

anyway as i said the whole little gem MKII is in there. so i guess that would be it....

EIDT: Once again im sorry for not being able to post full schematics.. maybe in future after the paranoid dude wakes up

 

Nigel Goodwin

Super Moderator

Most Helpful Member

• Apr 13, 2008

• #15

It's an n-channel FET, and it's used to give a high input impedance for a guitar - I've always used a 2N3819 for such purposes in the past.

You could certainly use a TL082 to do the same job (and do it better), but it would need a little redesigning.

 

audioguru

Well-Known Member

Most Helpful Member

• Apr 13, 2008

• #16

The N-channel FET will have the even-harmonics distortion of a vacuum tube. The TL081 will have extremely low distortion and will sound different.

 

Papabravo

Well-Known Member

• Apr 13, 2008

• #17

Nigel Goodwin said:

.... but it would need a little redesigning.

Click to expand...

Aye, matey.... Thar's the rub

 

Krumlink

New Member

• Apr 13, 2008

• #18

Are you kidding? Just because I point out that a single picture is not very helpful I get hit with this? BE REALISTIC!

 

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ericgibbs

Well-Known Member

Most Helpful Member

• Apr 13, 2008

• #19

hi Krumlink,

As Atomsoft has already posted:

https://en.wikipedia.org/wiki/JFET
https://en.wikipedia.org/wiki/Unijunction_transistor

As Nigel also states its a, n Channel FET eg: type 2N3819
The p channel FET has the gate arrow in the opposite direction eg: type 2N3820