Re: 5W HF PA - setting bias current


Arv Evans
 

Setting the bias current with no load may be risky.  If there is any 
oscillation in the finals they could be destroyed.

Arv
_._


On Tue, Jun 9, 2020 at 11:49 AM Martin <marting7mrv@...> wrote:
As I understand it, by adding a temporary link to load the DA shift register with 255, I can set the bias point by monitoring the supply current drawn, with no need for any RF drive.

Is this all there is to it? As theres no drive, do I take it that there is no requirement to terminate the output? Or, does the output require at least to 'see' a 50 ohm load?

I will be adding this amp into my 6-band U3S case,

Regards
Martin G7MRV

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