Hi Jim,
Am 25.10.2016 20:12, schrieb [email protected]:
Would
the GPS units that you mentioned below suffice for the 50uHz bandwidths
that could be useful for TA attempts?
Yes they will. For example, i generated this spectrum peak (attachment)
in a 4.1 uHz FFT bin width with SpecLab and my remote stream from the
tree. The signal was generated locally with SpecLab and another GPS
module. Look at the sharpness and frequency resolution.
The distance is 3.5 km but real equipment was used.
But
the Trimble units have also been quite a burden for these applications
because of the power requirements, including a battery and
inverter/converter for the Trimble that is awkward and noisy (EMI) for
these portable weak-signal experiments.
Oh, this sounds complex. And it sounds like the power consumption is
much higher than 3.3V*45mA = 150 mW. My module is running 24/7 on the
solar powered tree. It slowly becomes challenging there, see
http://www.iup.uni-heidelberg.de/schaefer_vlf/DK7FC_remote_Grabber_tech.html
so power consumption is an issue.
The 60-meter square TX loop is in a remote area far from any
buildings or climate control so I may still try to use Trimble units
there
My tree too! :-)
On the tree:
https://dl.dropboxusercontent.com/u/19882028/ULF/20160409_170603.jpg
For portable recordings:
https://dl.dropboxusercontent.com/u/19882028/ULF/20160730_165911.jpg or
https://dl.dropboxusercontent.com/u/19882028/ULF/VLFesULF%20portable%20recording.jpg
Some, that's right! :-) Yes, these are the ones. And the price is quasi
the same.
Good luck with your tests!
73, Stefan
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