RE: LF: VLF in VO

[<hvanesce@comcast.net>]

Paul,

Ref: " I can easily see 10uW from 1000km in one hour over a path with a lot
of land.  West to east over water will be lower loss and four or six hours
integration will make up for the lower ERP."

Would you tend to allocate another 10db-15dB or so of loss for waveguide
coupling efficiency given horizontal polarization and low-order mode? (long
paths favor low-order modes, and low-order modes couple inefficiently to the
waveguide when polarization is horizontal). NEC seems to think that the
waveguide coupling penalty for (electrically small VLF) horizontal antennas
is about 15dB but I don't put much trust in NEC solutions for electrically
small VLF antennas.   

Jim
AA5BW


-----Original Message-----
From: owner-rsgb_lf_group@blacksheep.org
[mailto:owner-rsgb_lf_group@blacksheep.org] On Behalf Of Paul Nicholson
Sent: Sunday, December 20, 2015 4:40 PM
To: rsgb_lf_group@blacksheep.org
Subject: Re: LF: VLF in VO


 > About 30 watts were fed to a 5:1 XFMR and a ~0.35H  > tuning coil to the
100m wire at 10m height.

 > The ERP was about 3uW.

How about a long carrier, GPS or rubidium?  It's a long shot but it's a low
loss path and the time of year is good for several hours of coherent
integration.

I can easily see 10uW from 1000km in one hour over a path with a lot of
land.  West to east over water will be lower loss and four or six hours
integration will make up for the lower ERP.

--
Paul Nicholson
--