▁forward ▁bi ased . ▁ ▁This ▁causes ▁a ▁base ▁current ▁and ▁much ▁larger ▁collect or ▁current ▁to ▁flow . ▁ ▁The ▁positive ▁half - cycle ▁of ▁the ▁signal ▁is ▁ampl ified ▁in ▁the ▁collect or . ▁During ▁the ▁negative ▁half - cycle , ▁the ▁base - em itter ▁j unction ▁is ▁reverse ▁bi ased ▁and ▁hence ▁no ▁current ▁flows . ▁No ▁output ▁flows ▁during ▁the ▁negative ▁half - cycle ▁of ▁the ▁signal . ▁Thus ▁the ▁positive - only ▁ampl ified ▁output ▁is ▁un fa ith ful . ▁ ▁A ▁sufficient ▁battery ▁source ▁in ▁the ▁base ▁circuit ▁keeps ▁the ▁input ▁circuit ▁forward ▁bi ased ▁even ▁during ▁the ▁peak ▁of ▁the ▁negative ▁half - cycle . ▁ ▁When ▁no ▁signal ▁is ▁applied , ▁a ▁DC ▁current ▁I ▁C ▁ ▁will ▁flow ▁in ▁the ▁collect or ▁circuit ▁due ▁to ▁the ▁battery . ▁ ▁This ▁is ▁known ▁as ▁zero ▁signal ▁collect or ▁current . ▁▁ ▁The ▁value ▁of ▁zero ▁signal ▁collect or ▁current ▁should ▁be ▁at ▁least ▁equal ▁to ▁the ▁maximum ▁collect or ▁current ▁due ▁to ▁AC ▁signal ▁alone . ▁ ▁References ▁ ▁Category : Trans ist ors ▁Category : Sem icon duct or ▁devices <0x0A> </s> ▁Paul ▁Ritter ▁( 4 ▁March ▁ 1 8 2 9 ▁– ▁ 2 7 ▁November ▁ 1 9 0 7 ) ▁was ▁a ▁German ▁architect ural ▁painter ▁and ▁et cher . ▁ ▁Biography ▁He ▁was ▁born ▁at ▁N ure m berg . ▁He ▁was ▁de af ▁and ▁d umb ▁from ▁the ▁fourth ▁year ▁of ▁his ▁life . ▁A ▁pup il