Only a few days into use here but have noticed this evening - with a band of very heavy (thundery)showers out to the N and East of this location(Torquay) that reception in those directions is between awful and poor - the number of received signals being down at times to only one or two- and with signals dropping in and out.
Just wonder what other users experience of this is - I know UHF sigs can be very weather sensitive.
We get the same here. We overlook the river Trent, and storms/rain follows the river up towards the humber.
The frequencies being used are very short wavelength, thus can be distorted by rain etc
Quote from: malc41 on April 28, 2009, 06:49:15 PMThe frequencies being used are very short wavelength, thus can be distorted by rain etc
27cm wavelength, and yes, just the same effects - during the recent fine weather with HP hanging around, some very good results.
Rain attenuation isn't generally a significant factor at 1GHz (it starts becoming a big problem above 10GHz as you move closer to the water absorption line) and rain scattering will hit you at around 3-5GHz. Perhaps on weak, bursty signals it would have an effect on contacts at the edge of your coverage ranges.
Thanks for comments....
BTW- I'm not talking about your ordinary shower of rain - Rather the kind of rain I'm talking about is the cats & dogs (plus frogs) kind!
There's a good section on Rain attenuation in Introduction to Propagation (Seybold) including the ITU rain attenuation model to play around with, scientific calculators in hand... and a strong coffee in the other
Hi WAL 2T, whether it's rain attenuation or what I don't know, but thick low cloud definitely makes a significant difference to my reception.
Cloud below a planes height will affect radar. Thats when I hear strange throttle ups and downs when the planes can't be observed visually or are just plane noisy!
Water vapour attenuates radar frequencies also sat tv.