[Amps] 2879 biasing

[Steve Thompson]

----- Original Message -----
From: Gene Bigham <jbigham2 at kc.rr.com>
To: <amps at contesting.com>
Sent: 22 August 2003 19:18
Subject: [Amps] 2879 biasing


I have ordered a matched quad of these transistors to put into my mobile amp
and need to build a bias supply for them.  Reading G3SEK on the subject gave
some good pointers.  I want to use this behind a radio shack 10 meter radio
that puts out about 25 watts.  Any further pointers or places to look for
info would be appreciated.
--------------
The circuit Ian describes is simple and effective - other solutions I'm
aware of are either more complicated or inferior, so why not try it? Another
effective circuit is one used in Motorola app. notes with a 723 feeding an
emitter follower. There's a selection of Motorola app. notes at:

http://rf.rfglobalnet.com/library/ApplicationNotes/categories/1.htm

For my interest, is there a definitive origin for the two transistor
circuit? I first saw it in Philips designs from the 60s.

Steve