2n3819 - UK Vintage Radio Repair and Restoration Discussion Forum

Mike Brett · 26th Mar 2010, 8:33 pm

Hello all
Anybody know the pinout for a 2N3819 as there is a lot of conflicting information on the web. And before you aske, no I do not know the make of mine. I know the gain is the middle pin but thats it.
Mike

Andrew2 · 26th Mar 2010, 8:52 pm

So it's not just me! I avoid using single-gate fets because of the utter, utter confusion! Give me a 40673 anyday - there might be four leads, but they're always in the same place.....

Variometer · 26th Mar 2010, 8:52 pm

In the past, I used quite a few of the 2N3819 FETs, but the GATE was in the middle.

Looking ito the base with the flat bit at the bottom, it was Drain, Gate, Source!

This from the book:
110 Semiconductor Projects For the Home Constructor, by R. M. Marston

Bob

jimmc101 · 26th Mar 2010, 9:10 pm

I've always used the Siliconix (Vishay) convention...
Looking at the pins with the flat at the bottom DGS (left to right).

The 'Siliconix FET Design Catalog' 1982 specifies the device as symmetrical (in the 'device geometry section), so swapping Source and Drain will have little effect on the performance of the device.

Jim

paulsherwin · 26th Mar 2010, 9:14 pm

Quote:

Originally Posted by jimmc101

I've always used the Siliconix (Vishay) convention...
Looking at the pins with the flat at the bottom DGS (left to right).

I've always assumed they are DGS too.

Paul

XTC · 26th Mar 2010, 9:15 pm

The datasheets do seem to differ, however they all have the gate as the middle lead.

I believe JFETs like the 2N3819 are symmetrical, so as long as you get the gate right, it doesn't matter.

Pete.

Mike Brett · 26th Mar 2010, 9:49 pm

Thanks to you all
I will stick with the general consensus and go with drain gate source. They don,t make things easy do they.
Mike

Damo666 · 27th Mar 2010, 1:07 am

The ones i used in the past were all drain, gate, and source as indicated above.

OErjan_S · 27th Mar 2010, 8:22 am

same here. DGS when looking at bottom and flat side down.

dim-bulb · 13th Apr 2010, 12:08 am

Not sure if this will help or hinder, but here's the link for the NTE equivalent for this device..

http://www.nteinc.com/specs/300to399/pdf/nte312.pdf

gianpaolo · 13th Apr 2010, 8:00 am

hello
I hope to help you
Gianpaolo

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Herald1360 · 13th Apr 2010, 12:41 pm

Naughty National!

julie_m · 13th Apr 2010, 1:31 pm

Why not use this as the excuse you need to treat yourself to this handy little gadget?

Tim · 13th Apr 2010, 2:29 pm

That DOES look useful. I do have a birthday coming up...............

Sean Williams · 13th Apr 2010, 6:44 pm

had one of those for a few years now....

Excellent bit of kit!

Sean

dave_n_t · 13th Apr 2010, 8:33 pm

I agree that the Atlas is a good piece of kit.

But it will only identify the gate of JFETs (like the 2N3819).
It cannot distinguish the drain and source (because they are indistinguishable

!)

dave

26th Mar 2010, 8:33 pm	#1
Mike Brett Retired Dormant Member Join Date: Dec 2005 Location: Wisbech, Cambridgeshire, UK. Posts: 452	2n3819 Hello all Anybody know the pinout for a 2N3819 as there is a lot of conflicting information on the web. And before you aske, no I do not know the make of mine. I know the gain is the middle pin but thats it. Mike

26th Mar 2010, 8:52 pm	#2
Andrew2 Nonode Join Date: Mar 2010 Location: Dukinfield, Cheshire, UK. Posts: 2,038	Re: 2n3819 So it's not just me! I avoid using single-gate fets because of the utter, utter confusion! Give me a 40673 anyday - there might be four leads, but they're always in the same place..... __________________ Andy G1HBE.

26th Mar 2010, 8:52 pm	#3
Variometer Retired Dormant Member Join Date: May 2008 Location: Preston, Lancashire, UK. Posts: 428	Re: 2n3819 In the past, I used quite a few of the 2N3819 FETs, but the GATE was in the middle. Looking ito the base with the flat bit at the bottom, it was Drain, Gate, Source! This from the book: 110 Semiconductor Projects For the Home Constructor, by R. M. Marston Bob

26th Mar 2010, 9:10 pm	#4
jimmc101 Heptode Join Date: Mar 2009 Location: Portsmouth, Hampshire, UK. Posts: 674	Re: 2n3819 I've always used the Siliconix (Vishay) convention... Looking at the pins with the flat at the bottom DGS (left to right). The 'Siliconix FET Design Catalog' 1982 specifies the device as symmetrical (in the 'device geometry section), so swapping Source and Drain will have little effect on the performance of the device. Jim Last edited by jimmc101; 26th Mar 2010 at 9:10 pm. Reason: spelling

26th Mar 2010, 9:15 pm	#6
XTC Retired Dormant Member Join Date: Oct 2004 Location: Bristol, UK. Posts: 837	Re: 2n3819 The datasheets do seem to differ, however they all have the gate as the middle lead. I believe JFETs like the 2N3819 are symmetrical, so as long as you get the gate right, it doesn't matter. Pete.

26th Mar 2010, 9:49 pm	#7
Mike Brett Retired Dormant Member Join Date: Dec 2005 Location: Wisbech, Cambridgeshire, UK. Posts: 452	Re: 2n3819 Thanks to you all I will stick with the general consensus and go with drain gate source. They don,t make things easy do they. Mike

27th Mar 2010, 1:07 am	#8
Damo666 Hexode Join Date: Jan 2010 Location: Blackburn, Lancashire, UK. Posts: 399	Re: 2n3819 The ones i used in the past were all drain, gate, and source as indicated above.

27th Mar 2010, 8:22 am	#9
OErjan_S Retired Dormant Member Join Date: Mar 2007 Location: Skelleftea, Sweden Posts: 250	Re: 2n3819 same here. DGS when looking at bottom and flat side down.

13th Apr 2010, 12:08 am	#10
dim-bulb Retired Dormant Member Join Date: Feb 2010 Location: New Germany, Nova Scotia, Canada Posts: 28	Re: 2n3819 Not sure if this will help or hinder, but here's the link for the NTE equivalent for this device.. http://www.nteinc.com/specs/300to399/pdf/nte312.pdf

13th Apr 2010, 8:00 am	#11
gianpaolo Triode Join Date: Jun 2007 Location: Milano, Italy Posts: 15	Re: 2n3819 hello I hope to help you Gianpaolo

13th Apr 2010, 12:41 pm	#12
Herald1360 Dekatron Join Date: Feb 2007 Location: Leominster, Herefordshire, UK. Posts: 16,536	Re: 2n3819 Naughty National! __________________ ....__________ ....\|____\|\|__\|__\_____ .=.\| _---\__\|__\|_---_\|. .........O..Chris....O

13th Apr 2010, 1:31 pm	#13
julie_m Dekatron Join Date: May 2008 Location: Derby, UK. Posts: 7,735	Re: 2n3819 Why not use this as the excuse you need to treat yourself to this handy little gadget? __________________ If I have seen further than others, it is because I was standing on a pile of failed experiments.

13th Apr 2010, 2:29 pm	#14
Tim Dekatron Join Date: Jan 2003 Location: Bradford on Avon, Wiltshire, UK. Posts: 3,310	Re: 2n3819 That DOES look useful. I do have a birthday coming up............... __________________ "Nothing is as dangerous as being too modern;one is apt to grow old fashioned quite suddenly."

13th Apr 2010, 6:44 pm	#15
Sean Williams Dekatron Join Date: Feb 2005 Location: St.Ippolyts, Hitchin, Hertfordshire QRA IO91UW Posts: 3,518	Re: 2n3819 had one of those for a few years now.... Excellent bit of kit! Sean __________________ Engineers make things work and have spare bits when finished

13th Apr 2010, 8:33 pm	#16
dave_n_t Hexode Join Date: Sep 2003 Location: Cheltenham, Gloucestershire, UK. Posts: 298	Re: 2n3819 I agree that the Atlas is a good piece of kit. But it will only identify the gate of JFETs (like the 2N3819). It cannot distinguish the drain and source (because they are indistinguishable !) dave __________________ Dave Teague