[Antennas] Terminating resistor

[Nelson Wittstock]

I'm thinking about putting up a Pennant antenna for low noise reception on
160 meters.  My concern is that I'm unclear as to what to use for a
terminating resistor.  The non-standard values that are called for have me
puzzled.  How does one come up with a 945 or 903 ohm resistor?  I suppose a
potentiometer could get this value and then be placed in a weatherproof
container but there has to be a better way.  Any suggestions would be
appreciated.

Nelson Wittstock, K8DJC