North Korea has been from the beginning of
March continually signal jamming radio broadcasts on the shortwave frequency
used by the South Korean non-profit broadcaster Unification Media Group (UMG).
Given the present situation, in which North Korean residents might be
influenced by outside information condemning the regime and explaining the
purpose of the sanctions imposed by the United Nations, the regime has showed the will to block sources of outside information that might cause unrest.
The shortwave frequency in question–7515
kHz, in the 41 meter band–has been actively jammed, making it extremely
difficult for North Korean listeners to tune in. On the 15, UMG began using three receivers to test out reception at that and adjacent
frequencies on a daily basis and was able to confirm that the exact signal is
The blocking effort is being concentrated
on the time period from 10pm- midnight. Specifically, from 10-11pm the jamming
is very strong. The signal jamming is undetectable from midnight to 1am. The
signal blocking became weaker at midnight on March 15, from which point onward
the entire three hour broadcast was audible. Starting on the 17, UMG moved the
frequency, but the jamming operators seemed not to notice because the
interference continued on the old wavelength.
Unification Media Group estimates that the
North Korean authorities are the responsible party. From the very outset of the
consortium’s radio leg activities, which date back to December 2005, the regime has
frequently looked for ways to jam its frequencies. While sporadic jamming has
been common over the past decade, it has had limited impact on receivers.
However, starting from March of this year, stronger jamming signals have been deployed.
The result: fuzzy reception and sometimes even completely blocked signals. This
is the first time that such a strong jamming effort has been continuously
“This is the strongest signal jam in the
last few years. As the regime is pushed into further isolation by the
strongest round of sanctions yet, they have become concerned that the residents
will be awakened by exposure to outside information,” Unification Media Group
(UMG) President Lee Gwang Baek said.
“North Korean authorities can not signal
jam at high strength across multiple channels, so right now, the most effective
thing to do would be to expand our frequencies and signal strength. We need
direct [South Korean] government assistance to do that.”
If the government were to grant permission for
civil society organizations broadcasting to North Korea to use the former’s powerful
and far-reaching medium wavelengths, the broadcasts would be able to reach far more people despite the jamming
About this, National Intelligence Service
First Deputy Director Yeom Don Jae said, “The regime’s efforts to block radio
signals from South Korean civic groups is actually confirmation of the potency
of these broadcasts. This will cause considerable agitation for the listeners
who have become accustomed to tuning in to foreign radio.”
He added, “Therefore, we need to let the
North Korean residents know about this situation and use the strength of the
regime as a weapon against them. We need to use multi-dimensional methods to
pump the North full of information.”
UMG currently broadcasts from 10pm-1am
nightly on shortwave frequencies via a transmission station in Dushanbe,
Tajikstan. This content is rebroadcast daily from 3-5:00am on AM and FM frequencies
via towers in South Korea’s Gangwon Province; however, these channels are
borrowed from other private broadcasters and therefore limited in range and
potency relative to those allocated by the government.