Looks good Roger - Im also following Stefans request - http://kl7uk.com/VLFAlaska.html The roll off in sensitivity is intentional at the "HF" end. Antennae is loop out in the woods to Jims design plus preamp, The preamp is in the shack and battery powered - AC power still increases noise so I have some work there. DHO38 is a good signal and better than the probe - the loop being placed so hopefully the house and its noise is in the loops null, well to some extent. The White line at 21.4kHz is my strongest reference station NPM from Hawaii, just about due South of me, and a haunt of many Alaskans this time of year
The loop is still firing North South over the Poles and shoving the loop at 90 degrees will give another set of signals! The Asus XONAR DX 192Kb/96 card is proving to give cleaner results than the bog standard, and another Creative 24bit sound blaster USB card is under test.
No luck running Ham radio delux, Windows 7 and USB/Serial remote control of the R75 as I get Blue screens after a period so have temp put control over to another XP machine, also giving another sound card. I have control OK, and that took a lot of getting the "right "driver from Prolific but something isnt liked.
A busy day yesterday digging snow and moving snow burms from A to C via B. Fired cables back over trees and the large 500/137 vertical is back up and connected. Coll fingered stuff as temps around -20C
Laurence KL7 UK Wasilla Alaska
Date: Tue, 28 Dec 2010 21:11:09 +0000
From: [email protected]
To: [email protected]
Subject: LF: VLF noise measurement
Following Stefan's suggestion I'm currently recording the VLF noise 0-24kHz at my QTH using the earth electrodes and small FET tuned preamp. Results are being uploaded to my grabber at https://dl.dropbox.com/u/15047843/xbm.jpg . The 24 hour period will end around mid-afternoon Wednesday.
Comments on the results would be appreciated - e.g. how this compares with other station results, what would reduce the noise floor etc.
73s
Roger G3XBM
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G3XBM GQRP 1678 ISWL G11088
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