DX University™
A Guide for DXers and DXpeditioners
Audio Studies
The audio files listed on this page illustrate various situations that are often heard in DX pileups. They
are excerpts from real pileups recorded directly off the air in MP3 format. The files are recorded in
STEREO with the DX station on one channel, and the pileup on the other. For best results listen in
stereo with stereo headphones or ear buds. While you listen, imagine tuning the pileup looking for the
station the DX operator is working. Studying these recordings could help you to gain an advantage.
Other than length, no editing of any sort has been done. The text included with each button may explain
what is contained in the recording, or it may simply allow the listener to determine for him/herself what is
happening. Additional recordings will be added from time to time. You can make and study your own
recordings with relatively simple equipment.
Study -- TX6G, 20 meter SSB, 26.March, 2014, 1225Z
Study -- TX6G, 80 meter CW, 24. March, 2014, 1250Z
This is a stereo recording of FT5ZM on 30M, 29 January 2014 startling at about 1530Z. At
this point, the FT5ZM operator is having some difficulty picking calls out of the pileup, and
there is lots of confusion. QSOs are not happening regularly. As a result, there are numerous
stations calling during QSOs, when it should have been apparent that calling was not in
order. The problems seem to be feeding off of each other. Carefully studying this piece might
be very revealing. (I might change the commentary after listening more.)
This is a stereo recording of FT5ZM on 10.115 at 1508Z on 29. January, 2014. There is
some general pileup audio followed at about 8:09 minutes by an interesting attempt at a
QSO betwen FT5ZM and WB7B. While the FT5ZM operator was trying very hard to get
WB7B in the log, many others -- some very prominent DXers -- were clearly calling out of
turn, QRMing the attempt and wasting time. WB7B did everything right, and in the end
succeeded. To his great credit, the FT5ZM operator persisted. The whole process wasted nearly four
minutes. See if you can identify the worst culprits.
This is a continuation of the STEREO mp3 recording of a TN2MS pileup on 12M. It picks up
at 2112Z, October 16, 2013. Again, we offer no comment other than to suggest that you listen
carefully to the pileup channel.
This is a STEREO mp3 recording of a TN2MS pileup on 12M at 2100Z on October 16, 2013.
The operator is doing very well and his frequency is reasonably clear, although there are
some "flareups." We offer no comment other than tosuggest that you listen carefully to the
pileup channel.
Martti, OH2BH operating Z81X, South Sudan on 21.290 SSB at about 1920Z, 29.April, 2013.
Martti listening initially for W6/W7 in his usual calming style. He didn't work many 6/7 in this
piece, but he is working NA and listening periodically for 6/7. The pileup is difficult to hear in
Wyoming, but I did find many of the stations he was working. Note the lack of commotion.
STEREO recording of John, G4IRN at XR0YG on 15M CW working the US and some Japan
early in the operation. John is definitely one of the better pileup opeators. The pileup is huge.
His procedure is working well -- he's sending 35 WPM, probably too fast, in general, but it's
working. Later in the operation this speed would not work so well -- There is no DQRM
(deliberate QRM), just a few calling on his frequency as he's sending "up" after every QSO.
Note how fast John finds the next station. This sequence would also be good practice for finding the
station the DX op is working. What is happening, though is that a large number of callers are calling
again even after he's identified a station -- maybe a partial -- and sent the report. This may be due to the
high speed, callers not understanding who he has come back to, or simply not beliving that he found
someone so quickly(!)
STEREO recording of TX5K on 75M SSB. 0200Z on 7. March, 2013. XE1L operating by the
numbers.
STEREO recording of TX5K on Clipperton Island, 6. March, 2013. Operation is on 15 meter
CW. The pileup receiver is set for 2.4 kHz bandwidth. TX5K Working a very large pileup of
European stations. Note that even though the speed is high, the operator is not identifying
often and it not sending "UP" after each QSO, there is very little QRM or disruption on the
DX frequency.
STEREO recording of T48RRC, 12. February, 2013 on 17M CW at 2145Z. He is possibly
preparing for the 2013 ARRL DX CW contest. He is working mostly JAs. He is listening UP
about 2 kHz, but neglecting to indicate where to call, UP in this case.
Audio Studies