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Loggings => Utility => Topic started by: ka1iic on November 07, 2015, 1812 UTC

Title: WWV 25000KHZ very loud at this time 1810UTC
Post by: ka1iic on November 07, 2015, 1812 UTC
Best copy on WWV on 25000KHZ I have heard... 1811utc. Nov 7 2015

Get UR rigs up and going it looks like joy on the upper HF frequencies...

73
vince
ka1iic

BTW  I just checked WWv at 20000khz and the 25000khz signal is stronger (much) than the 20000khz signal.  Propagation seems to be 'north/south'
Title: Re: WWV 25000KHZ very loud at this time 1810UTC
Post by: R4002 on November 21, 2015, 1233 UTC
Whenever WWV on 25.000 (or 25000.0 since HFU is standardized for listing frequencies in kHz :)), always try tuning the 25000 to 30000 (or at least 25000 to 28000 range).  Most "export radios" (sold as "10-meter" radios but easily modified to cover more frequencies, almost always with a set of 40 "CB-like" channels plus a bandswitch and a +10 kHz switch to reach the R/C channels - 26995, 27045, 27095, 27145 and 27195.  Don't be surprised if you hear voice on these frequencies during a band opening) operate on one of several frequency "plans":

The most common one is the 6-band "plan" of 25615-28305 in 6 bands of 40 channels, bands labelled A through F which band D being the legal US FCC CB band.  Other frequency plans include the basic 3-band "uppers and lowers" which is simply 26515-26955 (lowers, or band C), 26965-27405 (CB, mid, or band D), and 27415-27855 (high/uppers, or band E).  You'll notice that the band designation actually carries over from radio to radio.  More modern exports designed for the European market are being sold with "RU mode" - RU for "Russia" with coverage from 25615-30115.  The RCI-29xx series of radios cover 26000-32995.  A variation of the 6-band export is the 12-band one, which can be 24265-29655 or 25165-30555. 

The 11-meter forum here at HFU - http://www.hfunderground.com/board/index.php/board,15.0.html (http://www.hfunderground.com/board/index.php/board,15.0.html) is the place the start with.  Check out some of my log threads over there.  :D

If propagation favors North/South, you'll likely hear activity from Latin America.  The taxi dispatchers will usually start at 25615 AM and go up in 10 kHz steps.  Mexico, Brazil and the Caribbean are usually extremely active.  Start with 26225 USB, then work your way through 26555 LSB to 26565 AM, 26575 AM, 26585 AM, 26705 AM, 26715 AM, 26915 AM and 26955 AM before you hit CB channel 1 (26965).  CB channel 38 LSB (27385 LSB) is another great indicator of band conditions.  Once you get above 40 (27405) and into the "uppers", try 27425 AM/LSB, 27455 USB, 27515 AM/LSB and of course, the International Freeband Calling Frequency - 27555 USB.  Latin America operates its own calling freqs, 26555 LSB, 26705/26715 AM, 27065 AM (CB channel 9), 27455 USB, 27665 USB and 27695 USB/LSB +/- 5 kHz for QRM, especially if 27700 is active with SSTV.

Things can get really interesting if propagation from Europe is open at the same time as Latin America.  There have been several instances where I heard UK FM CB channel 19 - 27781.25 FM clashing with Brazilian stations having a QSO on 27785 LSB.   :o

There's everything from the usual CB operators and freebanders in AM/SSB to Latin American taxicab dispatchers in AM mode (all over the place, sometimes inside 10 meters) to UK FM "27/81" CB (27601.25 to 27991.25 in 10 kHz steps) to SSTV on 27700 USB to Irish and UK Churches (legally, 26965 to 27405 in 10 kHz steps, AM/FM, 27601.25 to 27991.25 in 10 kHz steps, same as the UK FM CB allocation, and 27605 to 27995 AM/FM in the 10 kHz steps - Ireland only).  Most churches use FM mode, although some have been reported using AM mode and some have been reported outside the 26965-27405 and 27600-27995 ranges listed above.

The 25-30 chunk of HF is pretty fascinating stuff - and of course if 10 and 11 meters are active, then that means VHF low band (30 to 50 MHz) could also be open.  I've heard everything from fire departments in the 33020-33980 range to Fort Hood, TX range control on 30450 to Spanish language taxicabs every 10 kHz from 29750 to 35000 and sometimes even higher, all in FM mode.  Apparently there are some taxi companies in Brazil who operate in the 30000 to 33000 region in AM mode using modified CB/11-meter "export" equipment.