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Need some elect help



I am using a head lamp as a power load while designing and building the 
power supply.
I am trying to get 5v at 20A from a 13.8v source.
The design is an LM317 (variable voltage reg) feeding the base of a 2N3055 
in common collector cofigureation.
When I run the output (the emitter) of the 2N3055 at 8v into the load 
(lamp), I read 0.02A (20ma). Using the formula R=E/I, gives me a resistance 
of 400 ohms. P=E*I shows only 160mw's.

The transistor gets REALLY hot, but not enough to burn it out.

Man its been a while since I have done these calcs...


Julie Macfarlane
1981 MKI 2L 16v
Amsterdam NY

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