The voltage amplifier control panel, with the volume control, output fader and indicator lamp, is the same as that used on the PG-6, but the output fader is not used, because the equipment has only one voltage amplifier. The output fader should be left in its maximum position at all times.

The power amplifier control panel is similar to the power amplifier control panels described in section 204, except in two details. The PA-18B power amplifier panel has only one power switch and one monitoring jack. The operation of the panel is, however, the same as the operation of the PA-20A power amplifier panels. See section 206.

No main line switch is used on the PA-18B amplifier rack equipment.

214. Troubles on the PG-8 Equipment. -Since there is only one voltage amplifier unit and one power amplifier unit used with this equipment, it is important that the amplifiers be checked before the show starts, and a complete set of tubes, which have been previously tested, be kept at band for emergency replacement. Testing the equipment before the show starts may forestall trouble which might otherwise occur during the show.

See also Chapter XIV.

28