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[DX] milliherzimittaukset,WWV yms
Moro!
Itse yritän pitäytyä mittauksista relatiivisuuteen ja kahteen desimaaliin, vaikka
usein näkee ns "milliherzimittauksia", siten
Tiedoksi [mwoffsett]-ryhmästä:
Don't assume WWV is always right on frequency. There are multiple skywave modes on 5, 10 and 15 MHz and particularly at sunrise and sunset there can be Doppler shifts of 2-3 Hz as the reflection height changes. These HF standard time stations are really only any good for time, not frequency. It's why the major frequency ref stations are all on LF. You can also see skywave Doppler on most MW stations at those times, up to 0.5 Hz - and have you noticed the spectrum broadening caused by multiple diffuse reflections just before local sunrise?
Walter G3JKV.
S
**
No, joku voisi laskea Doppler-shiftin vaikkapa Aussille tai Chilen asemalle ...
73 tk
___________________________________________________________________________________
Ennakkotilaa WRTH 2006 nyt:
http://www.amazon.com/exec/obidos/ASIN/0823059367/hardcoredxcom/
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