Topband: QRM in Asia

[Nagi]

Hi Top Band friends,

At 09:26 05/10/16 -0400, WA4FKI wrote:
> Can anyone provide additional information about the "jammer" 
> on 160 meters. 

The situation of noise from mid-September reported by Watt, JA0DAI
below has not been changed yet. 
We have it everyday and have difficulty of QSO not only with DX but
also JA, ourselves.

The signal is 15dB over S9 with 500Hz CW filter on my FT-1000
when I use a beverage for Europe in 330 degree.
The center of the frequency seems to be around 1820KHz but
this mysterious signal is not so much different between center
and edge.
1665KHz to 1970KHz (300KHz width !) is strong noise but after it
becomes clear all of a sudden as well as almost no spratter.
Also I do not hear the second harmonic in here.
The appearance time shifts day by day but it comes within 3 hours
after the sunset and stays all night long.

According to the BBS about 160m in Japan, the derections from
each area presumed by null of small roop are;

JA1 : 290 degree
JA2 : 300 degree
JA7 : 270 degree
JA9 : 280 degree

We can conjecture the approximate emission area.

At 08:58 05/10/19 -0700, N7UA wrote:
> If you can, please send me a wav file recording the this noise as
> heard from your QTH.

Click below URL, My (our) old 160m friend Tok, JA7AO has mp3 file
of the noise.

http://ja7ao.sub.jp/1825CW.mp3

See you on 160m if the band is clear.

73,   Aki  JA5DQH / KH7A

************************************************************

At 23:13 05/10/13 +0900, JA0DAI wrote:

> A report form JA:
> 
>   We have been masked by broadband jamming signal all over the topband
> here in JA. Nobody transmits so long as nobody can hear.
> 
>   The signal is almost S9 with my small loop heading to West, usually
> noise level is S1 here. It does not sound like a woodpecker, but more
> like noise and a Noise Blanker is useless. It spreads from 1650 to 1950
> with peak around 1780kHz listening with 80m sloper antenna that is not
> resonant on 160m.
> 
>   The possible same signal was heard in December 04 and January 05, but
> it was very short period and not last over a day. Now we are observing
> this one nearly two weeks continuously form 1st of October.
> 
>   The strength builds up quickly after about 1 hour after our sunset time,
> it seems the transmitting site is located west of JA by 1 hour behind.
> 
>   We are now asking JARL and Japanese PTT to figure out where it comes
> from, but we have no info so far.
> 
>   If this is relating to a certain political/military intension in Asia,
> I don't know how we can manage it. Does anyone have a good advice please?
> 
>   Anyway we would like to see the low band season coming just around the
> corner.
> 
>   73...Watt JA0DAI (also WR3W)