For RF transmitter circuits, the efficiency is largely determined by the efficiency of the power amp (always abbreviated as "PA" in RF discussions).

对RF发送器来讲效率主要由功放(PA)的效率决定。

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While the speakers pushed out gobs of volume, all of the power was pushed using an external amp and mixer stuffed in a messenger bag.

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Because it packs a full-size USB port as well as a micro one and fast (2.1 amp) charging, the Power Station can also power up an iPad.

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It has Burr-Brown 2 Channel low-noise Op Amp, ELNA Audio Grade Capacitor and a R-core linear power supply - doesn't mean that much too you?

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