[Lowfer] Finally completed my LOWfer Variometer

[Peter Barick]

Congrats Andy,

Keep up the improvements/experimentation, seems like you're on the right track.

I maight add a hint about a LF loading coil. When I first saw your post on the vari coil and the main coil having 5.88mH and that the vari coil negated a chunk of that to an effective value of 3.28, I guessed you had too much to start with. While the negative brings it in tune, it does so and adds an unnecessary amount of resistance, R. A better approach would reduce the main coil turns to a value that supports a small amount in the vari coil to tune, say 184-190. That keeps the coil as small as possible, reducing R.

My case is a little different as my setup is rx only. When using the vertical T, the loading was brought to res. by trial to peak at 185. No further tuning. I did measure the L of the two coils I used, one high, the other lower and it was about 2.6mH.

Carrry on the good works -- Peter
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>>> "Douglas D. Williams" <kb4oer at gmail.com> 09/22/08 11:13 AM >>>
Andy,

I have you Q5 copy at 11:00am here in Watauga, TN. We are about 150
miles apart, so good job on your new coil! I never could get any copy
with your previous coil, so your new one is a huge improvement.
http://i81.photobucket.com/albums/j231/Goranothos/cap00011.jpg

-Doug KB4OER
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On Sun, Sep 21, 2008 at 8:26 PM, Andy - KU4XR <ku4xr at yahoo.com> wrote:
> Hello LOWfers:
>
> I finally finished constructing my LOWfer variometer for Beacon " XR ".
> I have it sitting in my floor next to the window where the beacon feedline comes in. I had no idea how much inductance I would need, so I just put tap points in a few places, and started winding the wire until I ran out of paint bucket. The inductance ended up at peak being 5.88mH and at dip, 3.28mH. I connected it in the line using the end tap points, and
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