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![]() "itoldyouiamnotiamnotgeorge" wrote in message ... "Jim Hampton" wrote in news:wk4yc.5577$HL5.1283 @news02.roc.ny: MUF has no bearing on sporadic e propogation. Sporadic e will appear as high as 144 MHz. Best regards from Rochester, NY Jim Jim, you have been hanging with the Cbers too long the MUF does have a bearing on sporadic e in fact it plays a major part, doesn't sound like you know what it means by your reply. "Phenomena related to Sporadic E" Other closely related propagation modes are sometimes confused with temperate-zone sporadic-E. Long duration meteor scatter is often difficult to distinguish from true sporadic-E. When the MUF is just below 50MHz, for example, random meteors may elevate the MUF to a useful level for a few tens of seconds at a time. At times, such scatter simply evolves into solid sporadic-E propagation and may serve as an early warning of E-skip conditions. During especially intense sporadic-E sessions, back-scatter may be evident. Back-scatter signals are much weaker than normal E-skip signals; they may exhibit multipath flutter (a hollow, from-the-bottom-of-a-barrel sound) or have a slight echo. Back- scatter signal paths are usually well off expected great-circle bearings, but focus on known sporadic-E reflection centers. The expected communication range via back-scatter is short (in the 300 to 1100km range); thus, back-scatter may be useful for making contacts between the normal tropo distance and the shortest E-skip distances. Back-scatter contacts maybe especially useful in "filling n" grid-square multipliers on 50MHz during contests, for example. Back-scatter has been observed on 144 MHz when the MUF was in that range. This classical analysis works well in many practical applications, and it has enabled many alert operators to anticipate 144 and 220MHz sporadic-E. It may also be helpful to keep in mind that the sporadic-E MUF often climbs very rapidly, but reaches 144MHz only one-tenth as often as 50 MHz. Correct, but I was thinking in the terms of what is published concerning future 'estimated' MUF, in which case they are looking for F layer reflection. Heck, if you consider the moon, 24 GHz has been successfully used - but I wouldn't consider 24 GHz as the MUF. The original post was stating that 11 meters (or 10) was dead. The consideration is that the sunspot cycle is in such decline that, normally, F layer propagation won't be available. My response was that sporadic e does exist - but not everywhere at once. The bands do open, despite the MUF being far lower in frequency. I get the feeling that you are simply trying to say I'm wrong; I was simply speaking out against the generalities. Best regards from Rochester, NY Jim --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.703 / Virus Database: 459 - Release Date: 6/10/04 |
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