Terry
That wire looks ok. I use ex decca about 3mm diam but I only need about 0.5
mH of inductance for loading my inv L system.
For a coil former I use a small laundry type bucket size container which has
a lot of air space slots about 50% air/solid so is efficient.
Litz is not really necessary. I have used 2.5 mm plastic covered elec wire
preferably the fine multi strand type, or the 7 strand type. It is not that
critical and Litz is probably only marginal better if you do not need too
much inductance.
If it helps, and keep it simple and efficient. I connect the drop wires (3
at present) from the inv L system to the top of Main Inductor as above and
the bottom of winding to another small inductor about 6 ins diam in series,
this inductor is tapped all the way for matching.
Move wire from bottom of main inductor to a tap point down the 6 inch coil
for best SWR( Resonance) then connect the coax centre wire from the shack
up several turns from the bottom (earth end which is earthed or connected to
some radial system) to achieve a 1:1 SWR, braid of coax is connected to
bottom of coil/earth/radials etc
This has always worked FB for me and appears to be efficient and simple. My
earth consists of several insulated radials lying on top of ground and
running across a field. One copper earth spike is incuded at base of antenna
connected to radials and base of tower for lightening protection
Other methods used for resonating antennas are variometers and link windings
at cold end of loading coil for RF transfer.
I stick to 50 ohms for the whole system, this makes it easy for testing and
maintainence with existing shack test gear
I hope this helps and hope to work you on CW soon on LF and MF
De mal/g3kev
----- Original Message -----
From: "Terry GW0EZY" <[email protected]>
To: <[email protected]>
Sent: Friday, December 16, 2011 3:59 PM
Subject: LF: RE: Re: RE: Re: RE: Re: Wellbrook Loop
> Mal
>
> Thanks for the encouragement. Last week I installed a pulley system in a
> 60ft tree in the field about 100 metres from my shack - just waiting for
> weather to improve to finish the job. The next job will be building a
> resonator coil. I have just seen an eBay ad for LITZ WIRE 10/44 250 ft at
15
> USD including shipping to the UK (the seller has more than 10 available).
Is
> this size any good for winding loading coils?
>
> I've not seen tin-lined plastic CH pipe, I'll look for that in the local
H/W
> store.
>
> I did walk down the private road (I think you were in Ireland at the time)
> but your antennas are nicely hidden! We will be visiting Scarborough again
> next year so if your invitation to call is still OK I'll let you know
before
> we travel.
>
> 73 Terry
>
>
>
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