To start the motor-generator set turn the starting switch to the "START" position. The indicator lamp to the left of the switch should then light.

Since the voltage of the 15 volt generator cannot be controlled separately, its voltage must be regulated by means of the 250 volt generator control. It is advisable to adjust the 15 volt generator correctly, and let the 250 volt and 1000 volt generators assume their voltage automatically because it is important that the storage batteries be kept properly charged. See section 51. If the 250 volt and 1000 volt generators do not assume approximately their correct voltage when the 15 volt generator is adjusted, notify the RCA Photophone service man.

The following tables give the readings which should be obtained at the various metering jacks. These readings should be checked each time the equipment is started. See section 170 for interpretation of jack designations.

CONTROL PANEL METER READINGS
Jack Designation	Reading	Multiplying Factor	Scale Reading	Actual Value
EAX2	15 volt generator voltage	2	6.5	13 volts
ECX50	250 volt generator voltage	50	5	250 volts
EB123X100	Plate voltage of voltage amplifier tubes 1, 2, and 3	100	5	500 volts
EB47X100	Plate voltage of power amplifier tubes 4 to 7	100	10	1000 volts

Two types of exciter lamps are used with RCA Photophone equipments. One type is rated at 5 amperes and the other at 7.5 amperes. The reading obtained when measuring the exciter lamp currents depends upon the type of lamp used. The exciter lamp currents are adjustable by means of the exciter lamp rheostats on the voltage amplifier panel. This current should be adjusted to a slightly lower value than the rating of the lamps.

The reading obtained for the "C" bias voltage of the voltage amplifier is the voltage of the "C" battery.

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