APEX
™
Exciter Incorporating FLO
™
Technologyr
DC Power Distribution
Theory of Operation
26
04s40
0.fm
03/08/07
888-2604-001
Page: 4-17
WARNING: Disconnect primary power prior to servicing.
• +15 Volt Float leaves UDC interface board at J5 pin 2, the return is J5 pin 1.
4.5.3.3
Down Converter Board Power
The down converter board receives its dc voltages (+/- 15 Vdc and +8 Vdc) from the UDC
interface board via connector J8. The down converter board supplies are listed below.
• +15 Vdc: Input power from UDC interface board via connector J8 pin 1
• -15 Vdc: Input power from UDC interface board via connector J8 pin 3
• 8 Vdc: Input power from UDC interface board via connector J8 pin 5
• An on board regulator produces -5 Vdc from the -15 Vdc supply
• An on board regulator pr5 Vdc from the +8 Vdc supply.
The following ia a list of entries on the down converter board status screen.
• +15 Vdc: Input power
• -15 Vdc: Input power
• +8 Vdc: Input power.
4.5.3.4
PLL Board Power
The PLL (phase lock loop) board receives its dc voltages (+/- 15 Vdc and +8 Vdc) from the
UDC interface board via connector J1, as listed below.
• +15 Vdc: Input power from UDC interface board via connector J1 pin 1
• -15 Vdc: Input power from UDC interface board via connector J1 pin 3
• 8 Vdc: Input power from UDC interface board via connector J1 pin 5
Several on board regulators are used to achieve low noise and excellent isolation between
the PLL board digital input/output circuits, 10 MHz reference oscillator, 128.9 MHz 1st
local oscillator (LO), and the 2ns local oscillator. This board contains seven on board +5
Vdc regulators, one +12 Vdc regulator, six +3.3 Vdc regulators, one +2.5 Vdc regulator,
and one +1.8Vdc regulator.
The following ia a list of entries on the PLL board status screen.
• +15 Vdc: Input power from UDC interface board via connector J1 pin 1.
• -15 Vdc: Input power from UDC interface board via connector J1pin 3.
• 8 Vdc: Input power from UDC interface board via connector J1pin 5.
