[Amps] Dual power supplies in EB104 4X MRF150 design

[Steve Thompson]

> Hi all,
> 
> I'm working on building a solid state amp based on the EB104 design, and
> cheaply.  The only constraint that is causing problems is the power
> supply.  It appears that a single 50V/20A is going to be pretty expensive
> while 48V/10A supplies are readily available as telecom surplus for pretty
> cheap.  Looking at the EB104 schematic (
> http://www.communication-concepts.com/eb104.htm) it seems probable to power
> each MOSFET pair from a separate supply with only the need for an additional
> isolation capacitor.
> 
> Unfortunately the supplies I am seeing, usually Lambda, are not designed for
> parallel operation so that easy alternative is not an option.
If the supplies operate with constant current limiting then you 
can parallel them through diodes - a big bridge rectifier will 
give you what you need for very little. Add .05 or .1 ohm in 
series with each and you'll get a degree of current sharing as 
well, rather than one going into current limit all the time.

Steve