Go Back   Home > Forums > Amplifiers > Solid State

Solid State Talk all about solid state amplification.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Thread Tools Search this Thread
Old 27th February 2009, 09:57 AM   #1
qsa is offline qsa  Germany
diyAudio Member
qsa's Avatar
Join Date: May 2007
Default Need Assistance: To220 replacement for MJE720 or 2N2219a


Did somebody know replacement in TO220 case for MJE720 and 2n2219a devices.

MJE 720 is from Central Semiconductor buts its impossibile to get

2SD669a could be a good replacement but its not pin compatible,

This are High Speed devices and used in PA Power Amplifier as VBE


  Reply With Quote
Old 27th February 2009, 10:38 AM   #2
diyAudio Member
ostripper's Avatar
Join Date: May 2008
Location: Albany , NY (smallbany)
MJE 720 is from Central Semiconductor buts its impossibile to get
same as BD135/137/139G (Hfe 40 1.5A 40-80V)

2n2219 (in a can)

(10pf cob /50v/gain of 50)
This one isn't too fast either , even a 2n2222 (common) is
faster.. are these for a old amp?
  Reply With Quote
Old 27th February 2009, 08:19 PM   #3
mjf is offline mjf  Austria
diyAudio Member
Join Date: Jan 2009
Location: upper austria/near linz
2n2219a available at reichelt.de
ca. 0,3 euro per unit
  Reply With Quote
Old 27th February 2009, 09:27 PM   #4
anatech is offline anatech  Canada
diyAudio Moderator
anatech's Avatar
Join Date: Jun 2004
Location: Georgetown, On
Hi Peter,
2SD669a could be a good replacement but its not pin compatible,
Okay, so rotate the part so the leads line up.

The 2N2219 was a fast little thing, so if you can get by with a 50 mA device, a 2SC3423 would work well (200 MHz). The 2SC3421 has a transition frequency of 120 MHz, compared to the 2N2219A's 300 MHz rating and the 2SD669A's rating of 140 MHz.

The 2N2219A was a very common transistor, so you should still be able to scare one up somewhere. Many students taking electronics had these in there kits for their course. I imagine there must be thousands of these in closets around the world!

"Just because you can, doesn't mean you should" © my Wife
  Reply With Quote


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
High current TO220 diodes ceharden Solid State 11 24th November 2013 12:57 AM
Heat Sink Compound on a TO220? DreadPirate Parts 7 31st January 2009 02:43 PM
Peter's TO220/47 Insulator Question roddyama Parts 10 23rd January 2004 01:14 PM
7812 TO220 regulator little help please strulon Tubes / Valves 19 23rd May 2003 02:54 PM
TO220 5 lead package? trwh Parts 2 5th April 2003 12:03 PM

New To Site? Need Help?

All times are GMT. The time now is 07:22 PM.

vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright ©1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2