2014-06-24, 12:50
(2014-06-23, 21:36)RichoAnd Wrote: For outside use I suggest E-Field Antenna (easy to isolate) and an extra resistor as heater (100 ohm direct on coax terminals, only 0,2W??? ) - maybe resistor heater via extra wires ?
- PVC tube inside plastic foam tube
H-Field (loop/ferrit) can be placed inside, or outside in a thermobox - 5 volt heating resistor
http://vlf.stanford.edu/research/whistle...antarctica
http://wwlln.net/
/richo
As Richo suggests, you are going to need a heater. The parts are "industrial grade" good to -40C. I would be concerned about the electrolytic capacitors freezing at these temperatures. When I worked for an automotive supplier, we had a electrolytic capacitor that would freeze solid at -37C. This dramatically affects the capacitance value (82uF went to a few nF) and you will have all kinds of noise.
Make sure that whatever controls the heater is quiet! (both running and on/off events)
Greg