Message-ID: <4E4EE71C.5000207@toya.net.pl>
Date: Sat, 20 Aug 2011 00:43:40 +0200
From: Piotr Mlynarski <sq7mpj@toya.net.pl>
User-Agent: Thunderbird 2.0.0.24 (Windows/20100228)
MIME-Version: 1.0
To: rsgb_lf_group@blacksheep.org
References: <16BC8B3CA8672445BC2A29B4C14A26D4379ED2AAB4@exlnmb01.eur.nsroot.net> <4DF9EFD1.5010208@iup.uni-heidelberg.de> <1313780109.51443.YahooMailNeo@web111907.mail.gq1.yahoo.com>
In-Reply-To: <1313780109.51443.YahooMailNeo@web111907.mail.gq1.yahoo.com>
Subject: Re: LF: Ferrite wideband antennas?
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit
Sender: owner-rsgb_lf_group@blacksheep.org
Precedence: bulk
Reply-To: rsgb_lf_group@blacksheep.org
X-AOL-SCOLL-URL_COUNT: 0  
x-aol-sid: 3039ac1d40914e4ee74e7c86
X-AOL-IP: 195.171.43.25
X-AOL-SPF: domain : blacksheep.org SPF : none


Daniele Tincani pisze:
> Hello LF,
>  
> a very interesting discussion is in progress on the reflector on 
> ferrite rx antennas. My understanding however is that until now we 
> have been talking about narrow-band antennas. May I ask the experts if 
> a wide-band ferrite antenna could be feasible, able to (partially) 
> match the "panoramic" approach of SDR receivers, at least in the 
> LF/NDB and/or MW bands? Such an "ideal" antenna would combine some 
> advantages of air-cored loops with a reduced size (uhm... too "ideal" 
> to be real :-))
>  
> Regards
> Daniele
>  
Hello Daniele, LF

your suggestion about wide-band ferrite antenna has prompted me to 
another 'experiment' which i will try to make possibly in the 
forthcoming weekend.  Being 'triggered' by Stefan  ideas , constructions 
using large ferrite antenna
yesterday i have built a simple parallel LC network  followed by a 
buffer/amplifier where L has been delivered by  a fairly  large ferrite 
rod ...
The final receiving device was SDR-IQ of RFSpace.Inc    So far this sdr 
receiver has been  used  in the  VLF/LF region using  my  air loop ( 11 
turns, 1  sq. meter area, placed on my balcony)
along with the "wide-band" use of the OP27  - pse, see:  
http://ik4hdq.net/doc/testi/smlloop.pdf     for idea, details. scheme etc...
This setup has allowed me to successfuly receive Alpha (rsdn-20) stns, 
SAQ,  137 kHz transmissions/beacons and also some  air NDB's and
yesterday evening  it was used for comparisons between ferrite antenna 
and air loop ( dcf39 was used as signal source)
so, according to your question/idea - i simply replace my air loop by 
this ferrite antena therefore  will get a wide-band  ferrite antena 
configuration
and will do some rx'ing...
                                                                              
73, Piotr,sq7mpj

qth: Lodz/jo91rs/