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TEST OF THE PLATE CURRENTS OF THE POWER AMPLIFIER.
(See Section 169.)
MeterDesignation
Reading
Multiplying
Factor
Scale
Reading
Actual
Reading
IP FRONT
TUBES
Plate current of
front row of tubes
1
325
325
Milliamperes
IP BACK
TUBES
Plate current of
back row of tubes
1
325
325
Milliamperes

TESTS OF PLATE CURRENTS AND GRID VOLTAGE OF THE VOLATAGE AMPLIFIER
Jack
Designation
Reading
Multiplying
Factor
Scale
Reading
Actual
Voltage
IP1X1
Plate current of
Tube No. 1
1
3.3 to 4.5
3.3 to 4.5
Milliamperes
IP2X1
Plate current of
Tube No. 2
1
0.3 to 0.95
0.3 to 0.95
Milliamperes
IP3X5
Plate current of
Tube No. 3
5
2.5 to 5.0
12.5 to 25
Milliamperes
EC12X1
Grid bias of
Tubes 1 and 2
1
9 to 9.5
9 to 9.5
volts
EC3X5
Grid bias of
Tube No. 3
5
6 to 6.4
30 to 32
volts

When running sound-on-film the exciter lamp current should be checked. The reading to be obtained depends upon the type of exciter lamp used. One type is rated at 7½ amperes and the other at 5 amperes. Adjust the filament current to slightly less than the rating of the lamps used.

TESTS OF EXITER LAMP CURRENT.
Jack
Designation
Reading
Multiplying
Factor
Scale
Reading
Actual
Voltage
ILBX1
Plate current of
Tube No. 1
1
5 or 7.5
5 or 7.5
amperes
ILAX1
Plate current of
Tube No. 2
1
5 or 7.5
5 or 7.5
amperes
8


Chapter Thirteen Pages
[1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12]
[13] [14] [15] [16] [17] [18] [19] [20] [21] [22] [23] [24]
[25] [26] [27] [28] [29] [30] [31] [32] [33] [34] [35]

Chapter
[1] [2] [3] [4] [5] [6] [7] [8] [9]
[10] [11] [12] [13] [14] [15]

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