Received-SPF: neutral (gmail.com: 193.82.116.20 is neither permitted nor denied by best guess record for domain of owner-rsgb_lf_group@blacksheep.org)
Message-ID: <007601c69ac1$49227b40$1fc428c3@captbrian>
From: "captbrian" <captbrian@ukonline.co.uk>
To: <rsgb_lf_group@blacksheep.org>
References: <44A1A77C.22419.4C034E0@localhost> <3.0.6.32.20060628232029.00b76200@pop.netspace.net.au>
Date: Wed, 28 Jun 2006 15:43:53 +0100
MIME-Version: 1.0
Subject: Re: LF: Re:Spark
Content-Type: text/plain;
	charset="iso-8859-1"
Content-Transfer-Encoding: 7bit
Sender: owner-rsgb_lf_group@blacksheep.org
Precedence: bulk
Reply-To: rsgb_lf_group@blacksheep.org
Status: O

Ric,

That was great, for a minute I thought it read 4 inches and was google-eyed
at the thought of 100k volts.!  One-quarter inch makes sense at about 6Kv.
My old man, and my uncle by marriage, were both ops. at Fishguard coast
wireless station [GRL]  in the 1920s but my father changed his job when the
station moved about 1930 before I was born.  I wish I had quizzed him in
more detail before he went on to that great radio station in the sky but
various things he said keep coming back to me, some stimulated by these
exchanges. GRL was about as far west as one could get in UK for Atlkantic
ship traffic. RL stood for Rosslare in Ireland but station had to move
across to Wales when Eire became independent .

John, Ok I confess I had not really thought about _Ham_ radio  sparks, about
which I know nothing. Synchronous RSG were mechanically fairly simple by
being mounted on the same shaft as the motor-alternator set.  The audible
note  was that of the AC frequency [ or maybe twice that ?] sparks occurring
with both negative and positive peaks of the AC waveform. [Floridians note:
No , AC is not air-conditioning ;-)  ]

Bryan G3GVB


----- Original Message -----
From: "Richard Rogers" <vk7ro@netspace.net.au>
To: <rsgb_lf_group@blacksheep.org>
Sent: 28 June 2006 14:20
Subject: Re: LF: Re:Spark


> At 11:35 AM 28/06/2006 +0100, you wrote:
>
> snipped
>
> >BTW   I realise I have no idea of the length of the spark gap...anybody
> >know?
> >
> >Bryan G3GVB
>
> G'day,
>
> From a scrap of original copy (presumably from 600M) from Trevor Watkins,
> 7AA, later VK7DX who died in 1931 from TB (and too many late nights?) :
>
> 23rd May 1923
> 1.48 am VIM de VIA ur spark is not up to tem...
> VIA de VIM think gap open too much see ltr VIM
> 2.5 GUJ de GHM when are u due K
> GHM de GUJ about 4am
> 2.10 VIM de VJH hw this coil nw
> VJH de VJK coil gdo nw qru SK
> VIA de VIM wa abt 1 nr 4 inch apart hw
> 2.15 VIM de VIA gdo nw VIA tks VIM
>
> My guess is that the abbreviation gdo meant good-oh and that 1 nr 4 meant
> one quarter.
>
> VIA and VIM were coast stations in Adelaide and Melbourne and both used 5
> KW spark transmitters erected in 1912 and 1911 with an air blast to ensure
> a short duration of the spark and hence minimum damping and transmitted
> bandwidth.
>
>
>
> 73, Ric, VK7RO
>
>
>
>
>
> --
> No virus found in this incoming message.
> Checked by AVG Free Edition.
> Version: 7.1.394 / Virus Database: 268.9.5/377 - Release Date: 27/06/06
>
>