Electro-Metrics EM-2115, Instruction Manual

Page: 153 / 278

EM-2115 APPENDIX C FUNCTION AND DESCRIPTION
(EM2115C-14)
(Refer to Figures H.27 and H.28)
The Power Supply module supplies the regulated voltages used by the receiver and is lo-
cated at the rear of the unit. The circuitry within the module can be divided into three subcir-
cuits:
a. Rectifier circuit,
b. High voltage converter,
c. Regulator circuit.
The rectifier circuitry provides the "raw" DC voltages for the high voltage converter and
regulator circuits. The circuit consists of a power select module, power transformer, rectifier di-
odes, and filter capacitors. The power select module combines the power connector, fuse holder,
and AC voltage selector into one unit.
The regulator circuit provides the +12 VDC, -12 VDC, +5 VDC, -7 VDC regulated volt-
ages for the receiver. These voltages are produced by regulators operating from the +"Raw" and -
"Raw" supply voltages. These regulator consists of an integrated circuit module plus bypass ca-
pacitors.
The High Voltage Converter Module (A14A2) supplies the approx +150 VDC supply
voltage required by the Tuning Regulator and the IG Calibrator circuitry. The High Voltage Con-
verter circuitry operates from the "+Raw" and "-Raw" supply voltages.