RE: LF: MF: EbNaut

["Clemens Paul" <cpaul@gmx.net>]

Hi Paul,

I would recommend feeding DC not via the center tap of the output transformer
because the DC current is biasing the core which reduces its
"dynamic range" and increases losses and heat.
Instead I would feed DC via two separate DC chokes.
That's like it is done with HF PAs.
The cores of  my own push pull MW PA run much cooler since I use separate 
feeding chokes.
One can confirm the bad effect of DC biasing also with a spice simulation. 
There are also some professional articles around in the www covering this topic.
Maybe I can find one which I have stored on my PC a while ago.

73
Clemens
DL4RAJ 



>-----Original Message-----
>From: owner-rsgb_lf_group@blacksheep.org 
>[mailto:owner-rsgb_lf_group@blacksheep.org] On Behalf Of Paul Nicholson
>Sent: Monday, February 29, 2016 12:49 AM
>To: rsgb_lf_group@blacksheep.org
>Subject: Re: LF: MF: EbNaut
>
>
>Attached a circuit of part of the push-pull PA.
>
>The center tap of the primary is at AC ground with the
>DC supply coming in via a choke.
>