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Adam Sampson Adam Sampson is offline
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Default Sherwood RX-5502 Receiver Protection Shutdown, Repair, thoughts wanted...

"William R. Walsh" writes:

Alternative 3-terminal linear regs will still dissipate the same
amount of heat regardless of their current capability.

Okay...if you don't mind my asking, why is that the case?


Because that's how linear regulators work -- they behave like a sort of
intelligent resistor. If you regulate 28V down to 12V with a linear
regulator, the regulator acts like the right value of resistor to get
rid of 16V as heat.

You can do better with more modern regulators, but you need a switching
regulator rather than a linear one. National's "Simple Switcher"
regulators are good for this sort of thing; you pretty much just add an
external capacitor and inductor.

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Adam Sampson http://offog.org/