ARLA/CLUSTER: QRM nas bandas de amador.

[Carlos L.R. de A.Gonçalves]

O seguinte, que não é novidade... o "fenómeno" surgiu há já algum tempo...
foi extraído do Boletim BC-DX nº 775 / 29SET'06, www.wwdxc.de.

Se acaso alguns dos amadores-emissores já notaram tal QRM, aqui vai
uma explicação.

(...)
CHINA/TAIWAN    SOH  Sound of Hope withdrawal from a ham band?
Now operating on 13970, 14600 and 17330 kHz. Jamming Tx:
13970 kHz Hainan Tx.
14600 kHz Hainan Tx.
17330 kHz Mainland Tx (?).
(S. Aoki-JPN via NDXC-HQ, controler: S. Hasegawa-JPN, wwdxc BC-DX Sept 14)

10200  The Chinese jammer 'Firedrake' was reported recently on 10200 but
now seems to have moved to 10400. Noted here at 1410 with a good signal.
The jammer took a break from 1500 to 1505 and then continued.
(Steve Lare-MI-USA, dxld Sept 23)

On Sept 27th at 1630 UT on 10400 kHz. wb.
Last night (27 Sept) around 1255 UT, I was checking the Chinese firedrake.
10400, 14600 and 17330 were very strong but 13970 kHz were rather weak
with fading. Perhaps 13970 is on a different site or the antenna direction
is different.

I heard it sometime ago from a chinese forum that there was an audio
channel on a satellite with all the firedrake mx / noise, and it could be
used as the audio feed for the firedrakers...
(Yogesh, dxld Sept 29)

Sound of Hope seems to have settled on 10400, 13970, 14600 and 17330,
using all four freqs at the same time. 10400 can be traced (from the
jamming) from about 0900, the other ones from about 0500 at my location.
SOH on 17330 was heard just after 1300 today, but was gone before 1305, so
may have signed off, although the jamming resumed at 1305. 13970 may also
sign off rather early, but is hard to confirm. 14600 seems to have a
variable sign off, while 10400 continues into European darkness, when
China fades from 31 m.

SOH is rather strong on 14600 and 10400 and has the same programme with
synchronous audio on these two freqs, so the beams seem to be directed at
Central China, possibly in the Shanghai dialect. 17330 is rather poor and
13970 is very poor at my location. The programmes on the latter two freqs
have been different from each other and from the sce on the other two
freqs when I have been able to pick up SOH audio on all four channels.

The jammers on 14600 and 17330 are synchronous, while the other two have
different delays. The dominating jammer on 10400 stays on with open
carrier during the monitoring breaks and in one break I heard what
appeared to be a second, much weaker Firedrake jammer below SOH.

It should be noted that the Firedrake audio is a network "programme" that
is used from several jamming sites and is used by all jammers when CNR-1
is off the air.
(Olle Alm-SWE, wwdxc BC-DX Sept 28)

(...)
______________

Há escassos anos, a China colocou várias encomendas aos EUA p/ fornecimento
de txs destinados, sobretudo, a cobertura nac. e/ou regional, que funcionam
incl. nas chamadas bandas tropicais.

Curiosamente, são precisamente alguns desses mesmos txs que, fora "das horas
de expediente normal" são utilizados p/ o que tem sido relatado, de que o
conteúdo do boletim DX supra é um simples exemplo.

A maior parte do empastelamento por tais txs destina-se ainda a certas
emissões da R.Ásia Livre, outra invenção dos EUA.

73.
Carlos Gonçalves.