Dear Jan,
Thank you for your reply.
> Assume in JP MF BCST stations are also likely to disappear.
Never heard of that move in JA.
I guess, AM BCs' value is appreciated, after the earthquake and Tsunami
disaster in 2011.
NDBs are disappearing, but that's another issue.
> I assume that the 200m rule is not particular for BCST MF stations, but
> the fact that ADSL connection can suffer from slow modems.
Maybe yes,
Telephone lines here are being replaced by optical-fiber lines,
with Gigabit internet throughput,
so, ADSLs are decreasing, but there still are.
Yes, ADSL-interferernce is rather difficult to be detected,
but, BC-i is easy...
better be prepared, Hi.
Hideho YAMAMURA, JF1DMQ
> -----Original Message-----
> From: [email protected]
> [mailto:[email protected]] On Behalf Of pa3abk
> Sent: Sunday, December 21, 2014 11:42 PM
> To: [email protected]
> Subject: Re: LF: RE: Japan on 475 kHz.
>
> Dear Hideho,
>
> Assume in JP MF BCST stations are also likely to disappear.
> In NL it's expected that all MF station will be QRT within a year or 2.
> But NL is rather small and the internetconnections are very dense and most
> of them high speed (> 100Mb).
> A lot of alternatives available.
>
> I assume that the 200m rule is not particular for BCST MF stations, but
> the fact that ADSL connection can suffer from slow modems.
> Especially in countries were the telephone lines are above ground.
> JP is more widely and expect that rural connections are far most above
> ground.
>
> I remember a discussion in BlackSheep about this issue with Britisch Telecom.
> If I recall correctly the line check of ADSL is done in the same band we
> are using for MF. If the check interferes with the "our signals" the server
> will automaticly lower the internetspeed and finally to an unacceptable
> value. The user is mostly not aware and the provider software doesn't reveal
> why the connection is bad. At the end the provider will send a new modem.
> The user is happy with the high speed, until his neighbour starts WSPR again
> in the weekend.
>
> The emails are lost here but there was a PDF mentioned with an improved
> ADSL filter which could subside this issue.
>
> Jan/pa3abk
>
> Hideho YAMAMURA schreef op 21-12-2014 om 13:20:
> > Dimitris and all LF/MF,
> >
> > Yes, in JA, 630m will be permitted at EIRP 1Wmax., effective Jan.05, 2015.
> > Official Directive was published on Dec.17, 2014.
> >
> > however,
> > there are following conditions (I think, first announced on Oct.10):
> > (1) there are no house or office within 200m radius,
> > other than owned by the station owner.
> > (2) OR, agreements are obtained from the houses or offices within the
> 200m.
> > (3) on site test will be conducted before permission. ("for some time"
> they say).
> >
> > It seems that the officials have concerns on QRM to MF broadcast
> > signals, like 936kHz, 945 kHz, 954 kHz... the 2nd harmonic and/or 1413
> > kHz, 1422 kHz, 1440 kHz... the 3rd harmonics.
> >
> > Several stations are preparing LPF,
> > and are finding/found places for the on site test, as portable stations.
> > There is hot discussion on these on the internet in JA.
> >
> > I would like to know the situations in the already operating stations.
> > Do you have any BC QRM problem ? (I mean making interference, not
> > receiving), and what care do you take ?
> > LPF, what kind, other means ?
> > How much is your harmonic attenuation ? or filter attenuation ?
> > Information highly appreciated,
> >
> > BTW, I myself, is not prepared for 630m, yet.
> >
> > Hideho YAMAMURA, JF1DMQ
> >
> >
> >> -----Original Message-----
> >> From: [email protected]
> >> [mailto:[email protected]] On Behalf Of Dimitrios
> >> Tsifakis
> >> Sent: Sunday, December 21, 2014 8:26 AM
> >> To: [email protected]
> >> Subject: LF: Japan on 475 kHz.
> >>
> >> Hello group,
> >>
> >> I have received an email from a friend in Japan informing me that
> >> Japanese amateurs gain access to 630 m from 05/Jan/2015. There are
> >> some restrictions on power and vicinity to other houses. Does anyone
> >> have more information on this?
> >>
> >> 73, Dimitris VK1SV
> >
> >
> >
>
> --
> pa3abk <-> dordrecht jo21it
> Sent by Philips STB-75 with T100
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