Broadcast Electronics AM-2.5E, User Manual

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1-8
1-47.
POWER SUPPLY CIRCUIT GROUNDS.
1-48. The power supply circuit board is equipped with three isolated circuit grounds: 1) 0VS,
2) 0VP, and 3) 0VI. The circuit grounds are at different potentials and are not referenced
to earth ground. The 0VS ground is the circuit ground for the: 1) SCR controlled bridge
rectifier circuit, 2) soft-start control circuit, 3) ac line voltage detector circuit, and 4) low-
voltage detection circuit. The 0VP circuit ground is used to create the negative leg of the
B supply. The 0VI ground is the circuit ground for the: 1) crowbar circuit, 2) switching
regulator circuit, 3) inverting drive buffers, and 4) switching regulator transistors. The
circuit grounds are used in association with the circuitry to generate the operating volt-
ages for the RF power modules.