[Lowfer] WM in EN90xn

[N8OOU]

Mike - TTS,

Thanks for that great capture. I would say that it is the result of 
mother nature, and your filters.

I tested some changes in the Wm Helix Box yesterday which took the 
beacon up and down during the day. I experimented with different wiring 
configurations by adding in a re-wound AM BCB ferrite rod as an 
adjustable inductor.

My results ended up being net losses, so I restored the Box to my 
original configuration.  I am back to the same operating parameters I 
have been using for the past couple weeks.

I am curious to know if you have the filters open just for the pix, or 
will they be open all the time?

When I first got the "ham-it-up" converter I experimented for 3 or 4 
weeks trying different things to be happier with it's performance. Most 
of the work was putting various filters on it's input. That did bring 
the performance level up to something acceptable, but killed the concept 
of it being a "wide band" receiver.

Mike - OOU

73   de   N8OOU - Mike Meek

On 12/07/2014 03:58 AM, Michael Sapp wrote:
> Mike & All:  Best capture here yet of WM and at QRSS30 nornal this time....
>
> https://www.dropbox.com/s/9b1cd6nipf4jt3h/wmq30.jpg?dl=0
>
>
>      Not sure if how much of the above capture is band enhancement, as I built a new 9th-order Butterworh 300kHz LPF this evening and
> have it in line.  I am noticing a lower background noise level at the watering hole and at 137kHz. Seems like the MF~LF converter has more head room with
> more LPF roll off in the AMBC band...
>
>     https://www.dropbox.com/s/r1ile71ugrqergn/IMG_4143.JPG?dl=0
>
>
>      A few days ago I started experimenting with adding a few roll off caps to my 75>50 Ohm isolation transformer. The
> 50 ohm side is about 600uH and I found that switching 10nF and 22nF caps across the 50 ohm secondary did a reasonable
> job off reducing my AMBC overload (the LF EWE has relatively high signal levels from the local BC 50KW stations ) that remained
> with my existing 500kHz LPF.
>
>   Of course, an impedance matched solution is preferred, so I went to the AADE program and toyed around with various LPF designs until I found one I liked....
>
>     I'll find out soon enough if the LPF is helping the converter performance or if we just had good LF band condx this AM.....73 Mike wa3tts
>
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