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From: "James Moritz" <james.moritz@btopenworld.com>
To: <rsgb_lf_group@blacksheep.org>
References: <001601cc5147$61942b50$0401a8c0@xphd97xgq27nyf> <CAMFjj70bR2-tV4JjkVDAG4HbQsr-0JAvnuhQpRGNAVQO-AnqSQ@mail.gmail.com> <Pine.LNX.4.64.1108022222130.18043@paranoid.lipkowski.org>
In-Reply-To: <Pine.LNX.4.64.1108022222130.18043@paranoid.lipkowski.org>
Date: Tue, 2 Aug 2011 22:16:08 +0100
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Subject: Re: LF: Poor antennas
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----- Original Message ----- 
From: "Jacek Lipkowski" <sq5bpf@lipkowski.org>
> BTW it is incredible that nowadays people in north america are using 
> sophisticated receive setups with FFT to barely receive SAQ, and just 90 
> years ago they used crude receivers for a 24h/7 telecomunications service 
> between the continents without problems.

Dear Jacek , LF Group,

Well, perhaps it is not as simple as that. At 
http://earlyradiohistory.us/1922RCA.htm you can see a photo of some of the 
receivers used (fig 180 at the bottom of the page), with a rather brief 
description. Considering this was the early 1920s, the receivers were 
clearly rather complex, with many features added to attempt to reduce noise 
problems. They used full-wavelength Beverage antennas at remote locations, 
also to reduce noise. From reading this and other accounts, it is clear 
that, although undoubtedly there was much less man-made QRM than today, 
noise was always a serious limiting factor for VLF/ LF communications.

Cheers, Jim Moritz
73 de M0BMU