[time-nuts] Lucent RFG-M-RG and XO

[Gerald Molenkamp]

Some 5 years ago I recovered one of each, ( RFG-M-RG & RFG-M-XO ) from a Lucent CDMA BSC site here in Australia. Both units were only 12 months old, at that stage inter-connected via the J5 "interface" 10MHz out to 10MHz in from the RG to XO respectively and of course 24 VDC. 

After some reverse engineering of the BSC, I never understood the reason for the REG-M-XO in the BSC as it required a 10 MHz input from the RG for it to operate properly, e.g. the fault LED off. The 15 MHz signal is the synthesiser reference output that is fed into the BSC radio, synchronisation then propagates through the CDMA network, which I assume is used as one of many Primary Reference clocks ( PRC ) for the network of many BSC's. My assumption is that the XO is used as a back-up PRC in the event of RG failure, or as part of the hold-over system, but this was questionable.

For as many years as I have had both units, I have tried to obtain specific module data from vendors down here, but unfortunately none is available. However the LPRO Rubidium unit with-in the RFG-M-RG unit is an absolute ripper on it's own.

I do have the following pin-out data for the interface J5 from the RG to XO:-

RB DB9 Pin No.        XO DB9M Pin No.

1                                5
3                                3

RG & XO P1 DB9 power connector

1    +24vdc
2    0 vdc


The RG requires approx. 1.3 A @ +24vdc at start-up, the current drops to approx. 600mA. The XO requires 300mA, but drops slightly after warm-up.

If any one has more data, please let the audience know. I am keen to understand the need for a Rubidium PRC to disciple an oven controlled oscillator ( XO )?

Gerald