RadioReference on Facebook   RadioReference on Twitter   RadioReference Blog
 

Go Back   The RadioReference.com Forums > HF / MW / LW Monitoring > Shortwave Broadcast


Shortwave Broadcast - Discussions regarding shortwave broadcasters

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #1 (permalink)  
Old 11-29-2012, 6:57 AM
fleef's Avatar
Member
   
Join Date: Jun 2010
Location: Phoenix Arizona
Posts: 182
Default 6970 khz.. Firedrake

Unless the pirates have changed their taste in music.. strong firedrake on 6970 AM @ 11:53UT. No breaks, just pure clang and bang non-stop since 11:00UT.

OK, now they've suddenly ended transmission abruptly at 12:00UT on the dot.


location SW Arizona

Last edited by fleef; 11-29-2012 at 7:03 AM.. Reason: update
Reply With Quote
Sponsored links
  #2 (permalink)  
Old 11-29-2012, 11:08 AM
Member
   
Join Date: Jun 2010
Location: Mojave Desert, California, USA
Posts: 1,969
Default

Quote:
Originally Posted by fleef View Post
OK, now they've suddenly ended transmission abruptly at 12:00UT on the dot.
The Firedrake does stop at the top of the hour most of the time. It may or may not come back up on the same frequency, depending on the actions of the target station.

While I do not know for sure the reason for this stop, I strongly suspect that the stop at the top of the hour is “listen time” for the jammers. They kill the jammer, confirm that the target station is on the desired frequency, and then bring the jammer back on air. In the case of the Firedrake this return time is often anything from 5 to 25 minutes after the hour.

T!
Reply With Quote
  #3 (permalink)  
Old 11-29-2012, 10:52 PM
fleef's Avatar
Member
   
Join Date: Jun 2010
Location: Phoenix Arizona
Posts: 182
Default Thanks Token

Quote:
Originally Posted by Token View Post
The Firedrake does stop at the top of the hour most of the time. It may or may not come back up on the same frequency, depending on the actions of the target station.

While I do not know for sure the reason for this stop, I strongly suspect that the stop at the top of the hour is “listen time” for the jammers. They kill the jammer, confirm that the target station is on the desired frequency, and then bring the jammer back on air. In the case of the Firedrake this return time is often anything from 5 to 25 minutes after the hour.

T!
I was not aware of the "peeking in for a listen" time at top of hour. I wonder who they were trying to jam? Commander Bunny? lol unaware of any broadcasters on or around 6970k.
Reply With Quote
  #4 (permalink)  
Old 11-30-2012, 11:23 AM
Member
   
Join Date: Jun 2010
Location: Mojave Desert, California, USA
Posts: 1,969
Default

I noticed Firedrake came online on 6970 kHz at about 1518 UTC today, 11/30/2012. When the Firedrake dropped at 1600 UTC I did notice another carrier under it. The other startion does appear to be a Chinese language station, but I have nothing on any of my lists so I have no idea what station it is.

T!
Reply With Quote
  #5 (permalink)  
Old 12-08-2012, 6:48 AM
kilokat7's Avatar
Member
   
Join Date: Oct 2010
Location: West Michigan
Posts: 295
Default

In strong right now with a 20 KHz wide signal, 1140 UTC on 6970.
__________________
Perseus SDR | Phased BOGs & Double KAZ delta loop | My YouTube DX Channel
Reply With Quote
Sponsored links
  #6 (permalink)  
Old 12-11-2012, 11:53 PM
Member
   
Join Date: Nov 2003
Location: Columbia, SC
Posts: 100
Default

I've never understood why Firedrake shows up so often out of band, sometimes way out of band like on 13.9mhz.... Unless they are trying to jam military HF transmissions.
Reply With Quote
  #7 (permalink)  
Old 12-12-2012, 12:11 PM
Member
   
Join Date: Jun 2010
Location: Mojave Desert, California, USA
Posts: 1,969
Default

Quote:
Originally Posted by gpsblake View Post
I've never understood why Firedrake shows up so often out of band, sometimes way out of band like on 13.9mhz.... Unless they are trying to jam military HF transmissions.
Firedrake is not jamming military transmission. The SW broadcast stations that Firedrake is jamming often, but not always, choose out of band or edge of band frequencies, to be clear of other strong station interference. Firedrake jams where it jams because that is where its targets are.

For example, Sound of Hope uses (among others) 13920, 13970, and 14400 kHz, and so Firedrake can be found on those frequencies.

The thing that started this thread was the frequency that was being jammed, 6970 kHz, and the fact that no one reporting it was hearing a station under the jammer and no list showed a station there. I was sometimes hearing a weak station when the jammer dropped off-line at the top of hour, but could not ID the station. Since then it has been determined the station is probably Firedrakes favorite target, Sound of Hope and the most current B12 shows SOH on that freq.

So, Firedrake is jamming 6970 kHz whenever Sound of Hope is on that frequency, or when it is scheduled to be on that frequency. So far the schedule for SOH’s outlet on this frequency is not well defined.

T!
Reply With Quote
  #8 (permalink)  
Old 12-13-2012, 4:43 AM
Member
   
Join Date: Oct 2012
Location: Navarre (Pensacola) FL, USA
Posts: 29
Default

Not to mention, they use something like 500KW to send that out.. Gotta love China

-Rob
Reply With Quote
  #9 (permalink)  
Old 12-13-2012, 1:03 PM
Member
   
Join Date: Jun 2010
Location: Mojave Desert, California, USA
Posts: 1,969
Default

Quote:
Originally Posted by Rob_ View Post
Not to mention, they use something like 500KW to send that out.. Gotta love China
500 kW is just not that unusual on HF. At least half a dozen broadcasters use that kind of power, including Voice of America, several outlets in France, Iran, Dubai, Saudi Arabia, Turkey, Russia, and of course China (for other than Firedrake broadcasts). Dozens more are in the 250-300 kW range, only 3 dB down in power and essentially an indistinguishable difference on the RX end, in theory it is half an S unit on the meter if transmit antennas are comperable.

Jamming is an interesting world and at times it takes a different thought process to get your head around. I have often heard people say “this or that jammer is not very good, I can still hear the station”. However, jammers almost always have a specific target region in mind. They are denying that signal in a specific region that may be very tightly defined. Unless you are in that specific region you are in no position to judge the effectiveness of the jamming. The J/S (jammer to signal ratio) is an important part of the equation, and this plays into modulation techniques, location, beam steering, polarization, etc, etc.

T!
Reply With Quote
  #10 (permalink)  
Old 12-13-2012, 3:59 PM
Member
   
Join Date: Oct 2012
Location: Navarre (Pensacola) FL, USA
Posts: 29
Default

I know VOA out of Marathon (1.180) uses 100KW but Cuba is on the same frequency broadcasting the same thing!

-Rob
Reply With Quote
Reply

Tags
6970, china, firedrake, jamming

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -5. The time now is 12:29 PM.


Powered by vBulletin® Version 3.8.2
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
All information here is Copyright 2012 by RadioReference.com LLC and Lindsay C. Blanton III.Ad Management by RedTyger
Copyright 2015 by RadioReference.com LLC Privacy Policy  |  Terms and Conditions