2 meter bands opening up?

[kc9esf]

don't know if it was our local weather, but repeaters are comming in clearer and there have been reports of long distance communications happening.

anyone else hear anything outside of 9 land? hot and muggy here

[k4uug]

</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (tater1337 @ July 22 2004,10:34)</td></tr><tr><td id="QUOTE">don't know if it was our local weather, but repeaters are comming in clearer and there have been reports of long distance communications happening.

anyone else hear anything outside of 9 land? hot and muggy here[/QUOTE]<span id='postcolor'>
try this siteTropospheric Ducting Forecast (http://www.iprimus.ca/~hepburnw/tropo.html)

I made many SSB / CW contacts via 2 meters 70 cm useing this site! http://www.qrz.com/iB_html/non-cgi/emoticons/smile.gif enjoy

Tropospheric V/UHF DX Modes..
Line-of-Sight (GW)...is normal continuous reception where the receiving and transmitting antennas can see each other..taking into account the 4/3 Earth curvature of radio waves.

Tropospheric Scatter (TrS)...is ever-present under normal conditions. That's the mode that produces the distant fluttery signals that randomly fade in and out. These are your most distant regular stations that barely make it in. Depending on your location and equipment..tropo scatter can extend to 300..500..or even 700 km. The theoretical maximum limit for most TV/radio DXers is 800 km (500 mi) (Some semi-professional setups can extend furthur). Scatter is caused by small particles/droplets in the air such as haze, dust, volcanic ash, clouds, etc.

Tropospheric Enhancement (TrE)..(akaTropospheric Refraction) is common under normal conditions. On most clear nights with calm or light winds..the ground radiates and the air near the ground cools. Eventually an inversion is formed and signals begin to refract off the inversion. Stations that normally fade in and out via tropo scatter come in continuously..with increasing strength. Also..weaker tropo scatter stations that are normally not heard (because their signal strengths never cross the background noise threshold signal level) also begin to appear. When the sun comes up..the ground &amp; air heats up..the inversion breaks down..and the enhancement disappears. The enhancement is subtle on some nights..and very obvious on other nights. Distances are no different than your tropo scatter catches..it's just that the signals are stronger. Tropo enhancement is greatly influenced by terrain..with valley and coastal paths favoured. (&quot;Fog-prone&quot; areas are also &quot;DX-prone&quot; areas!!http://www.qrz.com/iB_html/non-cgi/emoticons/wink.gif. From a DXers point of view, multiple directions usually are enhanced at the same time.

Tropospheric Ducting (TrD)..is an abnormal condition. An inversion has formed at a much higher level above the ground...the vast majority of duct-producing inversions lie between 450 and 1500 m (1500 to 5000 ft)..with a few between 1500 and 3000 m (5000 to 10,000 ft). These inversions are not formed due to nighttime radiation/cooling..but rather because of some other weather phenomenon (high pressure subsidence aloft, warm frontal boundary, cold frontal boundary, oceanic or lake inversion, Chinooks, etc.). Because of this..ducting can occur day or night (though it strengthens at night)..is not usually influenced by terrain (the exception being large mountain chains like the Rockies)..and from a DXers point of view is usually either uni- or bi-directional. In fact..typical ducts are sharply directional. Signals refract off of and also travel along the inversion..thus the analogy of a duct. Distances are theoretically unlimited. One large area can have multiple ducts going on simutaneously..but they are usually parallel paths. It is possible in a very strong high pressure system to have large areas of ducting creating multi-directional openings. These are the rare &quot;blockbuster&quot; openings that make DXers' mouths water. They are most common over the oceanic areas in the tropics and sub-tropics.

Additional Characteristics of Ducting..
Ducting may or may not occur simutaneously with enhancement (caused by nighttime cooling). Often there is both a low-level radiational inversion caused by nighttime cooling (producing enhancement)...and a mid-level &quot;system-produced&quot; inversion above that (producing ducting). However..just as often there is only the higher duct-producing inversion..especially if the skies are cloudy or if it is windy. So..do not use your regular scatter/enhancement stations as propagation beacons for longer-distance DX acheived via ducting! Sometimes ducting can even display a &quot;skip-like&quot; character where distant stations on the same frequency and bearing can be received while closer-by stations are nowhere to be seen.

Ducting is also very height selective..with maximum signal transmissions at and just below the altitude of the inversion. DXers normally receive ducting DX via ground-based inversions. Occasionally inversions can be based above ground, in which case a DXer beneath the duct could completely miss out on the DX opening. Meanwhile, DXers at a higher elevation could, at the same time, be in the midst of a strong opening. It is also possible that a DXer at too high an elevation (above the top of the duct) could also miss out.

Ducting conditions usually vary over short time periods as opposed to enhancement which is more stable. Ducts located behind cold fronts (&quot;post-frontal ducts&quot;) are notoriously unstable as paths can even be interrupted by things such as heavy rain showers associated with the cold front itself. Expect the unexpected from these types of ducts with sudden and rapid changes in signal strengths quite common (some post-frontal ducts last only 15 to 30 minutes). High-pressure and oceanic ducts are a bit more stable and can last for days..but again expect the unexpected as changes can occur quickly.

Frequencies affected by ducting are determined by the vertical thickness of an inversion. Individual ducts will have a LUF (Lowest Usable Frequency) associated with them. Thin inversions (i.e.-thin ducts) will only propagate Microwaves. Thicker inversions will propagate UHF signals as well..while the thickest inversions will also propagate VHF signals. Unfortunately there is no reliable method known for forecasting inversion thicknesses. Also, in real-life tests, it has been found that reception at frequencies below the theoretical LUF is usually possible, although there is usually a sharp drop-off in signal strength at the LUF. See LUF page.


Lowest Usable Frequency (LUF) page (http://www.iprimus.ca/~hepburnw/dx/luf.htm)

[KB9YCO]

That's a good page, seems to be pretty accurate to what I hear. Good to see someone else posting links to it.
The conditions here in the northeastern corner of Illinois have been good off and on for the last couple of weeks. It's mostly the adjacent states, Indiana, Iowa, Michigan, central and northern Wisconsin, have been booming in; but, last fall we heard from the east and west coasts, in two meters! Unbelievable. 73 &amp; Enjoy .

[KB1JCY]

I'd like to try some 2m SSB. Who's going to be on the air tonight?

[KC8QMU]

Hey Tater,

A couple of weeks ago I worked Oklahoma and Arkansas from here in Ohio on 2M FM simplex.

What a blast!

It always pays to listen to .52! http://www.qrz.com/iB_html/non-cgi/emoticons/wink.gif

[WA7KKP]

Yes, tropo propagation of whatever variety is common in the summer months. Watch off-air television, especially Channels 7 and higher. When you see DX stations from outside your viewing area, there's an opening.

Best one I saw here in St. Joseph MO was KRSC Channel 35 (UHF) from Oklahoma. Watching the Wichita/Joplin/Springfield stations is quite common all year long. This is what you cable TV junkies are missing!!!

Gary WA7KKP

[KB9YCO]

Good opening again midday here in northeastern Illinois. It wasn't as good as some lately, and talking across Lake Michigan isn't extremely hard with even slight conditions; but, I did manage to talk into the repeater in Big Rapids Michigan for a good 10 minutes, reliably from the mobile with 25 watts on the 5/8. Not bad.

[AC4BB]

Why? #on #earth #would #a person #calling themself &quot;Tater 1337&quot; &quot; a handle #not #a real callsign &quot; #Be starting#a thread #about #what's #on 2 #meters.? # Blows my mind. # Tater, What's your callsign.?