The network of CW pulses I call “Pips” in my logs has been active the last couple of days, but on higher frequencies then I have seen in the past. I assume the good high freq conditions has driven them up a bit.
For those not familiar, some past threads on this network (there are more threads, these were just the first few I found):
http://www.hfunderground.com/board/index.php/topic,12307.0.htmlhttp://www.hfunderground.com/board/index.php/topic,12002.0.htmlhttp://www.hfunderground.com/board/index.php/topic,11983.0.htmlhttp://www.hfunderground.com/board/index.php/topic,11931.0.htmlhttp://www.hfunderground.com/board/index.php/topic,11459.0.htmlhttp://www.hfunderground.com/board/index.php/topic,11430.0.htmlhttp://www.hfunderground.com/board/index.php/topic,11429.0.htmlhttp://www.hfunderground.com/board/index.php/topic,10533.0.htmlhttp://www.radiohobbyist.org/blog/?p=1155The Pips network uses various pulse widths and timing sending dits or dashes on multiple frequencies. These dits have been seen as short as 0.062 sec to as long as 3 seconds. Pulse spacing has been seen from 3 to 10.5 seconds. All pulse widths and pulse spacing’s within a given transmission window are constant. The Pips are sent sequentially, normally cycling from low to high frequency. I mean it transmits a pulse on one frequency, cycles to the next higher freq and sends another, then to the next higher for another, etc. The pulse width and pulse spacing can be used to predict a possible number of frequencies used. For example a 0.7 sec long pulse width spaced 7.0 seconds apart allows for 10 possible pulse positions, and apparently 10 frequencies.
There appears to be two or more sources for these Pips (I have only seen 2 that I am confident in, and so I think only 2, but there could be more). Sometimes the two sources share a limited set of common frequencies. This can result in some frequencies having “different” and shorter pulse spacing, as each pulse from the two nodes are on separate timing. However, the pulses on all freqs are in sync, as on the shared frequencies the pulse timing between the two sources does not walk in relationship to each other. And pulses on shared frequencies are always deconflicted, they never overlap or collide, and so far (on shared freqs only) I have never seen them be timed so that one starts just as the other ends, there is always at least one pulse width between the pulses from the two sources, and normally several pulse widths. Normally out of say 32 frequencies only one or two will be shared (double pulse) meaning it is often possible to find almost twice as many frequencies in use as any one source should be able to provide based on pulse spacing.
Over the last couple days not only has the frequency been higher than seen (by me) in the past but also more frequencies have been shared. The pulse width has been ~0.7 sec long, and the pulse spacing has been ~7 seconds, allowing for 10 frequencies for each source. 11 frequencies total have been in use (during the time periods that I have reasonable confidence I have found all freqs), with only 2 frequencies being single pulse and 9 being double pulse.
In all of the below (1) means single pulse on freq, (2) means double pulse on freq.
Oct 29, 2013, tuned to in progress at 2350 UTC, transmissions ended ~17 minutes later at 0007:30 UTC, Oct 30.
21800 kHz (1)
25702 kHz (2)
26088 kHz (2)
26479 kHz (2)
26879 kHz (2)
27279 kHz (2)
27688 kHz (2)
28104 kHz (2)
28525 kHz (2)
28953 kHz (2)
29388 kHz (1)
After the above transmissions the network shifted frequencies, Oct 30, 2013, up at ~0010 UTC, off 0041:27 UTC. I only found 8 of the probable 11 frequencies, I now think they were at a high enough freq that propagation had faded for me on them (possible unfound freqs of 29388, 29555, and 29828 kHz).
16430 kHz (2) This freq used by Pips in the past
16680 kHz (2) This freq used by Pips in the past
17973 kHz (2)
18510 kHz (2) This freq used by Pips in the past
19070 kHz (2) This freq used by Pips in the past
20240 kHz (2)
25702 kHz (1)
26879 kHz (1)
The next day, Oct 30, 2013, 2150 UTC, tuned to in progress. Continued to 2206:10 UTC. Ended before I completed my frequency search, I had searched from 32000 kHz down to 20000 kHz before it ended, the two possible missing frequencies were likely below 20000 kHz.
20270 kHz (2)
20570 kHz (2)
20875 kHz (2)
21179 kHz (2)
21479 kHz (2)
21819 kHz (2)
22147 kHz (2)
25702 kHz (1)
29388 kHz (1)
10 seconds after the above ending it came back up on a new set of frequencies. Oct 30, 2013, 2206:20 UTC to 2242:30 UTC.
21800 kHz (1)
22497 kHz (2)
23158 kHz (2)
23858 kHz (2)
24579 kHz (2)
25330 kHz (2)
26088 kHz (2)
26879 kHz (2)
27688 kHz (2)
28525 kHz (2)
29388 kHz (1)
23 seconds after the above ended it came back up on a new set of frequencies. This set matched the set used in the last transmission sequence the day before. Oct 30, 2013, 2242:53 UTC to 2317:00 UTC. Not seen again after this set Looked for it off and on for the next several hours.
16430 kHz (2) This freq used by Pips in the past
16680 kHz (2) This freq used by Pips in the past
17973 kHz (2)
18510 kHz (2) This freq used by Pips in the past
19070 kHz (2) This freq used by Pips in the past
20240 kHz (2)
25702 kHz (1)
26879 kHz (1)
29388 kHz (2)
29555 kHz (2)
29828 kHz (2)
My log can create reports based on anything I want it to. I should have it make an HTML table of all the freqs used, with indications of the dates and times. This can show how this signal uses many different freqs, but also has a few it keeps coming back to over time. For example the 4 frequencies marked as used before in the last segment above, the Pips used those back in April of 2012, but with a 0.063 second pulse width and a 3 second pulse interval.
T!
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