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Author Topic: 11 meter DX Logs Sporadic-E Skip Conditions 24 February 2016 02/24/2016  (Read 3550 times)

Offline R4002

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Hampered by heavy storm QRN and local hiss noise (likely from a motor/engine somewhere - its all over the bands).  Frequencies listed in kilohertz as per HF Underground board standards.  As lots of 11 meter discussion deals with frequencies in megahertz (MHz), I'll include some conversions.  26715 AM = 26.715 MHz AM, 27065 AM = 27.065 MHz AM, 27555 USB = 27.555 MHz USB, etc.  

**Skip down to the bottom for today's discussion regarding the alpha channels or the "A" channels.**


26585 AM - Mexican/Latin American AM DX Trucker Calling Channel, busy
26595 AM - Similar to 26585 AM
26605 AM - Spanish language, Mexican accents, S9++ fading down to noise floor.  Sporadic-E?
26635 AM - Spanish language, YL and OM talking.  Locations in California and Mexico mentioned  Very rapid fading.  Music under OM's voice.  
26645 AM - OM reading numbers with music in the background.  Can't hear the station(s) he's talking to.  Guessing this is a taxi company
26715 AM - The usual "TOMA! TOMA! TOMA!" distorted audio from Puerto Rico, southern Florida, and elsewhere.  S9+20
26965 AM - CB Channel 1 - "I need to bring a handheld to work.  That's where I'm at all day".  Southern US accents
27025 AM - CB Channel 6 - The Superbowl.  "Motor Mouth Maul" and "Mr. Marlboro" heard, among various others.  Strong signals with fading
27065 AM - CB Channel 9 - Spanish language.  This is used as yet another Spanish language AM calling frequency
27085 AM - CB Channel 11 - AM Calling Channel.  11 is the original AM general calling frequency from the 23-channel CB days
27095 AM - CB Channel 11A - R/C channel.  Spanish language heard with roger beeps.  Rapid fades (see discussion at bottom of post)
27245 AM - CB Channel 25 - Spanish language taxi dispatcher heard.  Have heard her here several times before.  
27285 AM - CB Channel 28 - English language AM stations, very deep fading down to noise floor
27305 AM - CB Channel 30 - Hearing roger beeps at noise floor (noise floor is S-3 or so at 2100 UTC)
27405 AM - CB Channel 40 - "That does make things easier" - several stations heard at once.  None getting past S-5
27440 LSB - English language
27445 AM - Spanish language, likely taxi dispatch with roger beeps
27455 USB - Spanish language (Latin American 11-meter SSB Calling Frequency.  Supplementary to 27555 USB)
27485 USB - Spanish language.  Paraguay and Venezuela mentioned.  Weak, but readable signals.
27490 USB - US stations, midwestern accents heard
27665 USB - Spanish language
27695 USB - Spanish language
27775 AM - Spanish language, YL dispatcher reading numbers (probably a taxi cab company)
27805 AM - Truckers (English language).  Very deep fading and there may be a taxi cab dispatcher YL on the frequency as well
27835 AM - Spanish speaking OMs talking, more fading.  

Even though the regular CB band is 40 channels, and each "band" above and below it is 40 channels, there are actually 45 channels per band at the regular 10 kHz channel spacing.  Of course, for SSB purposes, that can be reduced down to 5 kHz spacing, giving a theoretical 90 channels per 450 kHz wide band.  That would give the "standard" 6-band export radio 270 AM/FM channels or 540 SSB channels.  Of course, in practice this isn't the case, as any AM channel is at least 6-8 kHz wide, sometimes much more if/when operators are running overmodulated radios that take up 20 or 30 kHz at modulation peaks.  The 5 kHz steps are the "gentleman's agreement" for the high band above channel 40 [27405 kHz/27.405 MHz] and stations calling on 27555 will often request a QSY to a "zero" channel to get away from QRM.  On several occasions I have heard SSB traffic "in-between channels" in the upper part of the legal 40 channel CB band.  Noted frequencies include 27370, 27380, 27390 and 27400.  27410 is also popular but I count that as a "freeband" frequency since its 5 kHz above 27405 and not between legal channels.  27370 and 27390 seem to be the most popular.  Generally the users of these frequencies are SSB operators who started a QSO on 27385 and then QSYed once they both agreed that they have radios that can reach the zero raster frequencies.

The "low bands" have much more limited use of SSB but the zeros are used there as well.  Commonly logged frequencies are bound to be stations going QSY from calling channels such as 26225 USB, 26285 USB and 26555 LSB.  Logged frequencies include 26230 USB, 26240 USB, 26500 LSB, 26520 LSB, 26540 LSB and 26570 LSB.  The 265xx frequencies all suffer from QRM due to heavy AM use of adjacent frequencies.  Don't believe me?  Next time there's a band opening, start at 26585 AM and tune up (or down) from there.   ;D

It is worthy to note that the "A" or "alpha channels" that are accessible via the +10kHz or +10kc switch on export radios give a total of 45 channels per band, even though there's only 40 numbered channels on a "street legal" or "FCC approved" radio.  These "hidden channels" translate to the upper and lower "bands" as well.  For example, channel 11A (channel 11 27085 + 10kHz = 27095) "down one band" (-450 kHz) is 26645.  Not all export radios have +10 kHz switches so these channels (25645, 25695, 25745, 25795, 25845, 26095, 26145, 26195, 26245, 26295, 26545, 26595, 26645, 26695, 26745, 26995, 27045, 27095, 27145, 27195, 27445, 27495, 27545, 27645, 27895, 27945, and, finally, 27995) are, usually, less busy than the other 40 channels in their respective bands.  They are often used by taxis and truckers looking for an "empty channel".  I've noted use of several of them on today's log alone.  The five A channels inside the legal CB band are also often busy during a band opening, and are very often overlooked.  Of course, these channeling issues don't matter if you're running a modified ham/general coverage radio with continuous tuning or a radio with a VFO added.  Some of the more modern export radios, for example the RCI-29xx series, the Magnum 257/357, the Lescomm/Lester's Custom Truckstop built radios and the DigiMax Lite frequency board add-ons include 45 channels per band, by adding the "A" to the additional channels i.e. 27185 is "19" on the channel display and 27195 is "19A".  
« Last Edit: February 24, 2016, 2156 UTC by R4002 »
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Offline Looking-Glass

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American CB heard quite strong at Mount Piddington (127kms west of Sydney) from 2200z Saturday 26th Feb 2016 with 27.025MHz AM the best performer, stations noted:

John Deere

Witch Doctor

Magnolia

West Side

Mod Squad

Some strong Hawaiian stations were noted at the same time on 27.085MHz AM talking to west coast USA, some very big signals suggesting some very big linear amplifiers being employed?  ::)
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Yaesu FT-1000D, Yaesu FT-2000D, ICOM IC-736 HF/50MHz, ICOM IC R75 & Tecsun S-2000 to 450 feet of wire, 27MHz 1/2 wave CB antenna converted to 21MHz & a multi band vertical of dubious reliability.

Offline R4002

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Big linear amplifiers and big antenna systems  ;D

Try 27.385 LSB as well as 27.025 AM and 27.085 AM next time the band is open.  Also 27.265 AM and 27.285 AM.  If you hear the big stations out of California you should also try the "low" and "super-low" bands for Latin American traffic - that is 26.065-26.955 MHz and then try the high band 27.415-27.855.  If you can hear SSB traffic on 27.385 LSB, there will likely be US stations on "freeband" or "outbband" frequencies like 27.425 LSB, 27.435, etc.  
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Offline Looking-Glass

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Thanks, I have heard quite a lot of Central & South American stations on 11m, especially on 27.555MHz USB, also many from the Caribbean and Cuba too. 

I was a CB pirate back in the 1970's before I was a radio amateur in 1975, was in the Earth, Whiskey and Alfa Tango.  Used to run a full Yaesu outfit for many years, started with a FT-200 (black cabinet) then had a full Yaesu FT-101E series station complete with FL-2100B etc.

I like listening to the regulars on 27.025MHz AM, especially John Deere and Magnolia, big signals with big opinions... ;D
Trundle, NSW.

Grid Square:  QF37ub

Yaesu FT-1000D, Yaesu FT-2000D, ICOM IC-736 HF/50MHz, ICOM IC R75 & Tecsun S-2000 to 450 feet of wire, 27MHz 1/2 wave CB antenna converted to 21MHz & a multi band vertical of dubious reliability.

Offline R4002

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Always awesome to see an "old school" freebander/CB op on this forum :D

27025 is usually my starting point when it comes to seeing if 11m is open.  Then I flip down to the low band (26515-26955) and start at 26555 LSB and 26585 AM.  The band is pretty open right now (1940 UTC, 04 March 2016)
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