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POE to linear power supply for Kiwi mounted at antenna feed
In order to minimize RF noise from my office and eliminate switching power supply noise, I have installed my Kiwi in a hermetically sealed 'garden box' and fed power over the ethernet cable.
I found a $10 9V switcher and feed it to the ethernet cable. At the garden box I cascade the two power supplies to minimize the power dissipated in the LM1083 linear regulators, so each LM1083 drops the 1A by 2V == 2 watts of dissipation. Under this operating condition the regulators are warm to the touch, so far below their thermal limits. The extra 4 watts of power dissipated in the box hasn't significantly warmed the box.
The dual supply is available for $14.50 on ebay: http://www.ebay.com/itm/182209407730