( ( ( Consisting only ) ( of ( ( ( an antenna ) and ) ( an ( audio amplifier ) ) ) ) ) ( , ( they ( ( are ( sensitive ( to ( ( radio waves ) ( with ( frequencies ( between ( ( a ( ( ( ( few hundred ) Hertz ) and ) 10 ) ) kHz ) ) ) ) ) ) ) ) . ) ) ) )
(ROOT (S (S (VP (VBG Consisting) (ADVP (RB only)) (PP (IN of) (NP (NP (DT an) (NN antenna)) (CC and) (NP (DT an) (JJ audio) (NN amplifier)))))) (, ,) (NP (PRP they)) (VP (VBP are) (ADJP (JJ sensitive) (PP (TO to) (NP (NP (NN radio) (NNS waves)) (PP (IN with) (NP (NP (NNS frequencies)) (PP (IN between) (NP (QP (DT a) (JJ few) (CD hundred) (CD Hertz) (CC and) (CD 10)) (NN kHz))))))))) (. .)))
Consisting only of an antenna and an audio amplifier, they are sensitive to radio waves with frequencies between a few hundred Hertz and 10 kHz .
(ROOT (S (NP (NNP Am) (NN radio) (NNS waves)) (VP (VBP exist) (PRT (RP in)) (NP (DT the) (ADJP (QP (CD 540) (TO to) (CD 1600))) (NN khz) (NN frequency) (NN range))) (. .)))