Rx connection buc 1326

Please check the exact text on the label(s) of the device you describe as "Andrew 1326 BUC".  Please copy all of the text here and we may be able to identify it.

An iDirect modem has two coax connectors. 

One coax is for receive and this is connected directly to a small receive module at the antenna called an LNB (low noise block downconverter).  The LNB requires a DC supply voltage  from within the iDirect modem.   The DC voltage may need to be 13V or 19V, a 22kHz tone may need to be on or off and a 10 MHz reference may be needed.  For simple LNBs either 13V or 19V alone will do.

The iDirect transmit cable is connected to a larger module called a transmit BUC (block up converter). The DC supply from the iDirect is sufficient for a 2 watt BUC.  I would guess the DC supply voltage is about 19 - 24 volts.  A 10 MHz reference is normally required to be on.  If you have a much higher power BUC, like 10 - 20 watts, then you will need a separate power supply, DC power cable and a DC block/power injector at some point along the transmit cable to the BUC.  Some high power BUCs will have separate AC mains or DC power input sockets and data cable sockets for remote control, monitoring etc.

I don't yet understand what you have.

Best regards, Eric.