[GPS_Standard] Frequency Standard Magnetic Field and Antenna Questions

[Harv Weiner]

Hello,

I am in the process of building the GPS-Derived Frequency Standard and have some questions:

1.  Most of the units I have seen do not have the power transformer in the same box as the OXCO and GPS. 
        
         Is there a concern about the magnetic field from the transformer?  What is the concern?

        If so, can the transformer be shielded, by a copper shield around the core or a steel cover?  I would like to put "all the pieces" in one box


2.  I have the Oncore UT+ GPS receiver and am wondering about the position of the antenna.  I can capture anywhere from 2 to 6 satellites 
    and the number varies with time.  The antenna is located in a window facing north.  Getting the antenna outside is difficult, since cable routing involves a tortuous path.

        Is this enough satellites for an accurate frequency calibration?

        The Oncore user manual is quite specific about antenna location and mounting. Do most users have the antenna outside? 

        Is there a recommended cable to minimize losses?

I am looking forward to completing this project so I can calibrate some test equipment.  Having a frequency standard with such accuracy on my work bench is an impressive addition.

Thanks!!

Harv
W1BMY