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 startiing 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.