[Lowfer] Excellent VLF condx this morning!

[Mitch Powell]

Jay:
Thank you very much - that's a full answer to all my questions - and gives me some
food for thought - for Winter preparation of the receiving antennas.
73

Mitch
On 2011-09-18, at 6:01 PM, <jrusgrove at comcast.net> wrote:

> Mitch
> 
> It used to be at 3' but the deer took an interest in it so I moved it up to about 8' AGL. Didn't see 
> much difference in signal or noise levels.
> 
> As far as the setup here ... it has evolved over a number of years. Eliminating all traces of crud 
> and reaching the 'natural' noise floor required a number of different 'fixes'. This is not a 
> particularly quiet location thus the following rigamarole.
> 
> First, it proved necessary to use battery/solar power to eliminate all power supply noise - no power 
> is fed from the shack. A coaxial cable common mode choke (16T FT-240-77) was required directly below 
> the e probe to eliminate 19 and 38 kHz 'products' from the 5000 watt FM broadcast station 2000' 
> away. This choke does almost nothing at VLF and would not be required if not for the nearby FM 
> broadcast station. The e probe has several sloping radials attached to it that also guy the mast. 
> Going down the mast, the coaxial cable encounters an isolation transformer/dc injector ( 
> http://www.w1vd.com/Eprobedcinjector.pdf ) at ground level where power from solar panel/battery is 
> inserted. The only earth connection is at this point as shown in the schematic. From there the 
> coaxial cable lays on the ground on it's way to the house. Before entering the house it encounters 
> another isolation transformer - same core/winding as in the dc injector. No earth ground is used at 
> this point. Routing of the coaxial cable to different locations in the house and to different 
> receivers and computer sound cards has no effect on the 'clean' noise floor.
> 
> I've also tried shielded twisted pair as feedline to the e probe (like I use to feed the large K9AY) 
> but there was no advantage over the coaxial cable.
> 
> Jay
> 
> 
> 
> 
> ----- Original Message ----- 
> From: "Mitch Powell" <mitch.powell at sympatico.ca>
> To: "Discussion of the Lowfer (US, European, &amp;UK) and MedFer bands" <lowfer at mailman.qth.net>
> Sent: Sunday, September 18, 2011 2:55 PM
> Subject: Re: [Lowfer] Excellent VLF condx this morning!
> 
> 
>> Hi Jay:
>> At what height is the Amrad ?
>> Assuming you feed with coax - do you ground the coax at the base of the support ( vertical 
>> portion ) ?
>> 
>> The base of mine is at 15 feet - with the coax grounded as it enters the ground.
>> 
>> Sounds like Dex is setting up for Frankenstein III ?
>> 
>> Mitch
>> 
>> 
>> 
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