AMPLIFIER
No. 143A FOR AMPLIFYING WEAK VOICES
AMP
& LS No. 4 - SPEAKERSET 1 - WAITING AMPLIFIER
AMP
& LS No. 5 - SPEAKERSET 2 - WAITING AMPLIFIER
AMP
& LS No. 6A - SPEAKERSET 3
AMP
& LS No. 11A - DORIC
AMP
& LS No. 12A - HARMONY
AMP
& LS No. 13A - USED WITH HERALD FEATUREPHONES
AMP
& LS No. 14A - USED WITH SL-1 FEATUREPHONES
AMP
& LS No. 16A - MELODY