The PG-13 equipments use two types of sound heads, one (Type PS-14) for the Powers 6B projectors
and one (Type PS-16) for the Simplex projectors. These sound heads are considerably different from
those used on the other types of equipments and are described in section 99. The turntable used is the
PT-10 described in section 73.
Only one stage speaker is used with the PG-13 equipment, and although it is of a slightly different
design from the other types of speakers its performance is practically the same. While one speaker is
standard equipment, two or four are sometimes used. This speaker is the Type PL-22.
222. Operation of the PG-13 equipment. -Before starting the PG-13 equipment see that the motor-generator set bearings are well oiled and that the commutators are clean.