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Old May 11th 12, 03:52 PM posted to
Token[_2_] Token[_2_] is offline
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First recorded activity by RadioBanter: Jul 2011
Posts: 10
Default 16.100Mhz 1000z-1200z

Firedrake is also known as Firedragon or Fire Dragon.

However, if the OP heard it for 2 solid hours without break he was not
hearing Firedrake.

The Firedrake jammer transmitters go offline at the top of each hour. Some
variable time later it comes back online, when it comes back on it can be on
the same frequencies as the previous hour or it can be on new frequencies,
or some mixture of new and old. This variable time when the transmitters
are off is anything from 4 to 25 minutes. The Firedrake can be (normally
is) on multiple frequencies at one time, I have seen up to 8 active at a
time and have been told up to 12 can be active. When it comes back online
after the top of the hour pause it comes on one frequency at a time, often
from highest to lowest.

For example, this morning, May 11, 2012, all Firedrakes transmitters went
offline at 1400 UTC. They came back on in the following order:

Time (UTC) Frequency (kHz)
1405:27 15605
1411:05 9985
1414:07 15490
1416:14 14700
1418:46 13130
1420:13 12300
1420:42 14800

The times I noted are the times the carriers came online. Often the carrier
comes up for a few seconds before the audio is switched in. The audio of
all Firedrake transmitters are in sync, so that the same notes are struck at
the same time on all frequencies, and it is thought the audio originates via
a satellite feed.

The reason for the pause at the top of the hour is unknown, however it is my
opinion this is what is called "look through" when talking about jammers.

A jammer that is active covers, by design, the signal it is jamming. This
means the source of the jammer can not be sure if the signal it is trying to
jam is still active or not. A well designed and reactive jammer will
periodically pause jamming to see if the target signal is still on the air.
If a jammer does not do this the target signal can use a technique of coming
up initially on freq A, waiting for the jammer to become active, and then
switch to freq B, knowing the jammer will not follow it.

Firedrake does not pause to look through, but it does normally come on to
jam a frequency only after the target signal has been on the air for many
minutes. The variable nature of the time it takes the transmitters to come
back online and the fact it comes back on one frequency at a time indicates
to me the entire process might be manual.

A couple of the stations Firedrake jams have, in the past, taken advantage
of this pause to get out announcements of upcoming frequency changes and
important news before the jammer comes on.

I have very occasionally seen Firedrake jam when no target signal was
present that I could find. However this does not happen often and when it
does I wonder if the operators are just hitting the freq because they
suspect they have no propagation conditions to hear the target. Other
nations jammers, such as North Korea and Vietnam, often come on and jam a
freq for days even though the target has abandon that freq and moved to
another. I get the impression those jammers are just hitting frequencies
based on a printed schedule or by direction.

Mojave Desert, California, USA

wrote in message
On Tue, 1 May 2012 09:33:30 -0700 (PDT), jdp

This morning I heard Chinese instrumental music at this freq. during
these times. Only music, no voice transmissions. Is this Central
People's BS in Beijing transmitting to Taiwan on an alternative freq.
from their usual 15.880Mhz? It was quite loud throughout the 2 hours
that I logged it. Very tinny instrument in the mix, probably a
Chinese So-Na (trumpet.)

Likely its a jammer (also known as the firedrake) from mainland China
covering the 100 watt station from Taiwan which is scheduled on this