[GPS_Standard] Power supply for stand alone GPS time base

[Feyssac jacques]

Hello All !
On this side of the pond we took the following schematic:
Main power supply :  28,5 volts SMPS 2,5 Amps powering the general BUS
1° Linear Fet regulator 27,6 volts 200mA feeding two 12 volts sealed batteries in serial
2° SMPS regulator delivering 21 volts to rubidium time base
3° SMPS regulator delivering 6 volts to three  low drop 5 volts linear regulators for powering :
                     - The VE2ZAZ control board
                     - The 10 mHz isolation/buffer/linear amplifiers powered only when a BNC is connected (to reduce permanent
                        power consumption
                     - The NMEA display
A diode switch will connect the battery suply to the bus in case of main failure, so there is no lost of synchro
We try by every ways to reduce the power consumption as the equipment is working permanently.
Final result is excellent without any spurious modulation to the 10 mhz signal
73 to all
Feyssac jacques