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Roger
A permit was never necessary for Dummy Loads, RF
pumped into the ground (induction) for any Frequency not just
LF/MF.
If one intends to transmit a RF carrier via an
antenna with the intention of being received by another then a permit is
required and this seems to be the intention of those now engaged on the DREAMERS
band
g3kev
----- Original Message -----
Sent: Wednesday, January 19, 2011 3:24
PM
Subject: Re: LF: Re: VLF Earth Mode does
NOT need an NoV - official at last
Hi Mal,
I am unaware of the situation with cave radio
and licences.
With regard to UK VLF experimenters I don't think it is
true that everyone necessarily wants to radiate a far-field signal as
far as possible. Certainly all the current NoV holders would like that,
although with my small antennas I don't hold out much hope here. There is
another set of experimenters who have for 40-50 years or longer played with
earth mode "through the ground" communications.
The 18.1.11 OFCOM email
does appear to give a tacit go-ahead for anyone to experiment with
essentially non-radiating earth mode conduction without real restriction on a
non-interference basis. To my knowledge, this is the very first time anyone at
a UK government telecoms authority (Post Office, MPT and now OFCOM) has
ever made this statement.
It may be semantics, but I believe
this is an important statement.
73s
Roger G3XBM
On 18 January 2011 18:34, mal hamilton <[email protected]>
wrote:
Two issues here
No NOV required for Earth Mode
(conduction/induction) applicable to Cave divers where it is not intended to
propagate a signal into the ether, but to communicate through the
earth.
however
Since it seems to be the intention by the
majority posting on this reflector interested in frequencies around 9 Kcs
and below to propagate/emit a radio signal to be intercepted some
kilometres or hundreds of kilokemetres then a NOV or Licence seems
necessary.
so
what is the object of this clarification,
it seems irrelevant to the intentions of most engaged in VLF experiments as
far as I can make out.
ie everyone is trying to emit a RF signal
with the best Far Field coverage hoping to cover the best
possible range, hundreds of Kilometres.
Is someone trying to
hoodwink OFCOM.
g3kev
----- Original Message -----
Sent: Tuesday, January 18, 2011 3:11
PM
Subject: LF: VLF Earth Mode does NOT
need an NoV - official at last
Today I received this letter from OFCOM, which
clarifies the legality of operating so called "earth mode"
(conduction/induction via the ground) experiments at frequencies below
9kHz in the UK. Note the sentence in Paul's letter saying, "We would not normally issue NoVs for
communications using non-wireless telegraphy apparatus/stations i.e.
where you rely only on conducted emissions and where there are no
intentional radiated emissions.".
Wanting to
check earth mode propagation behaviour at a series of frequencies
below 9kHz to see how results compared (earlier tests at 0.838kHz
seemed around 10dB better than at 8.76kHz), I asked OFCOM if I needed an
NoV extension to be legal. One could also argue that such tests at
frequencies above 9kHz would also be legal as long as it does not
cause any "Undue Interference to any wireless telegraphy" and
one was not intending to radiate.
This sounds a wholly
pragmatic answer from a government body.
Roger,
Rod Wilkinson has now left Ofcom , so
I’m responding to your query.
You should seek you own legal advice as
Ofcom is unable to give legal advice, however, we would issue NoVs,
where appropriate, for wireless telegraphy apparatus/stations.
In the case of the 9 kHz band NoV we
currently stipulate the frequency band only around 9 kHz as discussed
with the Met Office and we do not intend to issue NoVs for lower
frequencies in the band. We would not normally issue NoVs for
communications using non-wireless telegraphy apparatus/stations i.e.
where you rely only on conducted emissions and where there are no
intentional radiated emissions.
I would also draw your attention to
other relevant legislation (e.g. Wireless Telegraphy Act 2006) and the
Terms of the Amateur Licence and in particular to clause 7(3);
“Notwithstanding any other terms of this Licence, the Licensee
shall ensure that the Radio Equipment is designed, constructed,
maintained and used so that its use does not cause any Undue
Interference to any wireless telegraphy”.
I am also copying in Ash Gohil in the
Ofcom Licensing Centre who is in the team that Rod worked in. Please
address any further queries to him in the first instance.
I hope this helps.
Kind regards,
Paul
:: Paul
Fonseka
Spectrum Policy Group-Business Radio
+44 (0) 20
7981 3116
[email protected]
Hope this is of interest.
73s
Roger
G3XBM
--
g3xbm-qrp.blogspot.com/
www.g3xbm.co.uk
www.youtube.com/user/g3xbm
G3XBM GQRP
1678 ISWL G11088
--
g3xbm-qrp.blogspot.com/
www.g3xbm.co.uk
www.youtube.com/user/g3xbm
G3XBM GQRP 1678 ISWL
G11088
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