From: "Hans-Joachim Brandt" <hajo.brandt.dj1zb@t-online.de>
To: rsgb_lf_group@blacksheep.org
References: <3AD37870.409FD8D8@ieee.org>
Subject: Re: LF: More QRM ?
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Date: Wed, 11 Apr 2001 01:58:17 +0200
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Dear all,

in order to convert just words into figures I feel it necessary to describe the 
situation in Germany more in detail.

The german NB30 standard has been rejected by all german radio users and 
radio equipment manufacturers since it has been proposed. For those who know the 
british MPT 1570 the problem is that NB30 allows interfering fieldstrengths 20 
dB higher. But even the resistance of the german broadcasters could not prevent 
the adoption of the NB30 standard. The declared aim of the german government 
and the upper house of parliament has been to give "modern telecommunications 
technologies" a chance. The CENELEC standard on CATV systems covering 5 MHz to 
3000 MHz has also been aligned to the NB30 limits earlier, at least in the HF 
and VHF-UHF range. (NB is simply a german abbreviation for Nutzungsbestimmung = 
operational condition or regulation. There are other NB numbers within the 
german frequency allocation table.)

A radio amateur living in a house in which cables are operated under the 
conditions of the NB30 and having a half wave antenna 10 meters away from his 
house will have to expect the following calculated S meter readings: 

Band, MHz	1,8		3,6		7	14	21	28
NB30 
dB(muV/m)	37,8		35,1		32,6	29,9	28,4	27,3
S-Meter		S9 +12 dB	S9 +3 dB	S8	S6-7	S5-6	S5

I hope the table will be delivered in the same order in which I have typed it.

The second line gives the interfering fieldstrength permitted by NB30. The 
situation is bad, especially for QRPers. But all efforts of DARC to prevent such 
a decision were in vain.

Regarding the frequency depending levels of the NB30 it must be stated that it 
will allow VDSL and telecommunication over CATV, but only low-level PLC. 
High-level PLC producing interfering fieldstrengths of 80 dB(muV/m) or even 
more, is not permitted, this being the reason for the SIEMENS company to leave 
the PLC business some weeks ago. ASCOM (who now will supply power line companies 
which formerly had decided to use SIEMENS equipment) has claimed in a newspaper 
interview that NB30 low-level PLC would not enable a bit failure rate 
sufficiently low for 75% of all mains outlets. Therefore PLC becomes more costy, 
less dependable, repeaters are needed etc. The real winners of the german 
government decision seem to be those companies which will operate VDSL over 
telephone lines because they will have no (or only few) problems to meet the 
NB30 radiation levels. We know that in the U. K. the MPT 1570 (the range 1.6 to 
30 MHz, from December 1999) is also under pressure because its low levels even 
do not permit VDSL operation, but offers much better protection for radio 
services.

The European Commission is also in favour of PLC, because a network independant 
of the telephone net could be used. But after the PLC Forum had conducted a PLC 
workshop before the Commission, where strong opposition by radio users had been 
presented, the Commission is said to be at least unsafe whom to believe. But 
basically the Commission still thinks that a compromise with radio users should 
be possible, and still hopes that a standard would solve all problems.

For the time being, german radio amateurs hope, of course, that this german 
example will not be copied by other nations and that european standardization 
(especially the way being carried out in CEPT SE35) will result in lower 
interference radiation levels, for the benefit of radio services. And we also 
hope that the german administration will be able to effectively control the NB30 
limits throughout the country; otherwise a chaos would develop, no question.   

Sorry to report such a situation here over the server.

73 Ha-Jo, DJ1ZB


Andre' Kesteloot schrieb:
> Power lines win German support
> By Reuters
> March 30, 2001, 11:05 a.m. PT
>  FRANKFURT--Germany's Bundesrat upper house of parliament on Friday
> cleared
> regulatory hurdles for the so-called power-line technology for fast
> Internet
> access via electricity lines. A statement issued by the economics
> ministry
> in Berlin said three laws setting out the conditions for power-line
> operations had been approved, clearing the way for nationwide
> implementation
> in the 16 states in due course.
>
> The move gives power line the chance of competing with other established
>
> communications channels such as cable television and telephone networks.
>
> Analysts say that by delivering high-speed Internet connections through
> residential wall sockets, utilities could break the phone companies'
> grip on
> Internet access while also offsetting recent losses due to shrinking
> retail
> power margins.
>
> Story Copyright C 2001 Reuters Limited. All rights reserved.
>
>
>
>