the reason commercially manufactured transmiting loops are so expensive is 
because of the tuning capacitor.
even a used tuning cap that can handle the high voltage runs around $200. 
You can get air spaced caps far cheaper, but they're huge and somewhat more 
limited.
there is lots of detail on different options for the tuning cap on w2bri's 
website as well.
I suppose a person could use multiple coaxial stubs on the same loop, with a 
very heavy duty switch to change them for different bands.
this german made loop sounds interesting...and it shouldn't be too big of a 
deal to convert the operating voltage to north american standard.
$1200 is a bit steep though, unless the thing cooks breakfast for you and 
takes out the trash too.
73
Colin, V A6BKX
----- Original Message ----- 
From: "Eric Clegg" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Friday, February 25, 2011 6:45 AM
Subject: Re: magnetic loop antennas?


> Hello listers,
> Mfj makes two magnetic loop antennas 1 for 30 thru 10 meters and the other
> one for 40 thru 15 meters.
>
> There prices seem to range from under $400 to $469.00
>
> Wimo Electronics in Germany sells a really intriguing loop for over $1200.
>
> It has a key pad, you just enter the frequency you want to work with it 
> and
> it tunes the loop to resonance on that frequency.
>
> Unfortunatly, it only seems to work with 220 volts.
>
> There is also a guy from Brazil named Alex who makes two low power loop
> antennas for use with qrp radios.
>
> Hope all of this helps.
>
> Then there are receiving only loop antennas from companies like Aor and
> Wellbrook.
>
> 73,
>
> Eric
> KU3I
>
>
> __________ Information from ESET NOD32 Antivirus, version of virus 
> signature database 5906 (20110225) __________
>
> The message was checked by ESET NOD32 Antivirus.
>
> http://www.eset.com