We seek to understand and document all radio transmissions, legal and otherwise, as part of the radio listening hobby. We do not encourage any radio operations contrary to regulations. Always consult with the appropriate authorities if you have questions concerning what is permissible in your locale.

Author Topic: Wideband signal on 16 m and 11 m  (Read 5802 times)

Offline IZ5PQT

  • Newbie
  • *
  • Posts: 19
  • Pisa Italy JN53er
    • View Profile
    • Email
Wideband signal on 16 m and 11 m
« on: March 23, 2015, 1442 UTC »
Hello

I came across two puzzling signals which look very similar.
Their spectrum extends for 20 kHz: 17540-17560 kHz (S9) and 25920-25940 kHz (S9+10).
The shape is flat but with several peaks equally spaced. In AM mode it sounds like
a harsh 50 Hz or 100 Hz loud signal, but with different pitch in the two cases.
 Listened to in Pisa (Italy) with an
ELAD-FDM-S2 and a longwire.
2015.03.23
  • until 1430 both signals on
  • at 1434 both disappear
  • both for sure present also previous day
Screenshots
http://www.televideo.ws/Shared/23-03-2015 15-21-14.png
http://www.televideo.ws/Shared/23-03-2015 15-19-26.png
73 Giovanni
« Last Edit: March 23, 2015, 1518 UTC by IZ5PQT »
TXRX: IC-765ProIII
RX: R-5000, ELAD-S2,FRG-7, several SONY ICF-7600...
Antenna: 30 m longwire antenna, PA0RDT Miniwhip
QTH: Pisa, Italy, JN53er

Offline Token

  • Global Moderator
  • DX Legend
  • *****
  • Posts: 2118
    • View Profile
Re: Wideband signal on 16 m and 11 m
« Reply #1 on: March 23, 2015, 1836 UTC »
Without a recording (preferably in USB mode, widest bandwidth possible) it is difficult to be sure.  However this is almost certainly the British PLUTO radar, from Cyprus.  The bandwidth is correct (20 kHz is its most common swept width, but not its only width) , the appearance is correct, and the most common mode for this radar is its 50 Hz sweep repetition rate.

Go here ( http://www.hfunderground.com/wiki/Signal_Identification#Non_Communications_Modes ) look for the PLUTO entry.  Play the sound files.  Keep in mind those are recorded in USB, and will sound different than what you heard in AM.

T!
T!
Mojave Desert, California USA

Offline IZ5PQT

  • Newbie
  • *
  • Posts: 19
  • Pisa Italy JN53er
    • View Profile
    • Email
Re: Wideband signal on 16 m and 11 m
« Reply #2 on: March 23, 2015, 2012 UTC »
thanks! I suspected that it could be some OTHR. The information on PLUTO on the page suggests that I have really listened to it.

Giovanni
TXRX: IC-765ProIII
RX: R-5000, ELAD-S2,FRG-7, several SONY ICF-7600...
Antenna: 30 m longwire antenna, PA0RDT Miniwhip
QTH: Pisa, Italy, JN53er