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Technical Topics => Propagation => Topic started by: ChrisSmolinski on July 23, 2019, 1614 UTC

Title: Sporadic E, Es Propagation
Post by: ChrisSmolinski on July 23, 2019, 1614 UTC

Sporadic E propagation, by its name is sporadic and unpredictable by nature, but it enables radio signals to travel over much greater distances and often at higher frequencies than would normally be possible via the ionosphere.

Article: https://www.electronics-notes.com/articles/antennas-propagation/ionospheric/sporadic-e-es.php

Title: Re: Sporadic E, Es Propagation
Post by: R4002 on July 25, 2019, 1458 UTC

I love me some sporadic-E (Es, E-Sporadic, E-skip, among other names).  The awesome 11 meter and 10 meter band openings over the past couple months have been a lot of fun.  No VHF low band skip to note, but I imagine with a better receiver and more patience there's some stuff out there.  Unfortunately a lot of the previous VHF low band skip monitoring targets have partially or completed moved off the 29-50 MHz range.  25-30 MHz (mostly 25-28 MHz or 26-28 MHz) is still very much heavily used however. 

When the solar cycle peaks again, maybe California Highway Patrol will still be on lowband.  I remember listening to them on 42 MHz using a Radio Shack Pro-79 scanner and the factory rubber duck antenna indoors!  I could hear lots of military comms on low band (30.050 MHz, 30.300 MHz, 30.450 MHz, 31.000 MHz and several others would often boom in, it was only later that I found out that 30.45 MHz is Fort Hood Range Control primary, likely a simple 20 or 50 watt base station with a RC-292 or similar 1/4 wave ground plane antenna!).   I know Missouri Highway Patrol and several others are no longer on low band.   The NYC area cab companies, gypsy cabs, car services and similar comms would come booming in (30.6 MHz to 32 MHz, often mixing in with Spanish language chatter using the wrong frequency steps).  There are still tons of car services licensed in New York in the 30-40 MHz region. 

Sporadic-E is awesome.  When its really going, frequencies above 50 MHz / 6 meters and even the FM broadcast band can be enhanced....

Title: Re: Sporadic E, Es Propagation
Post by: BoomboxDX on August 13, 2019, 0604 UTC

Not much E-skip in my corner of the US (especially in the FM/VHF range), but when I had a 11 meter beam in 1990 I probably experienced some.

Title: Re: Sporadic E, Es Propagation
Post by: HERMANROCKS on October 22, 2019, 2122 UTC

Here in the Northeast, there is short skip everyday on 10 & 11 meters.

And great groundwave conditions, related to weather changes.



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