Order Tray | Contact Us | Home | SIG Lists

[aprssig] APRS buoy - transmit power and antenna?

Steve Noskowicz noskosteve at yahoo.com
Tue Sep 11 04:07:11 UTC 2007

 Oh, We noticed.  
   The attached "Line-of-Sight" spreadsheet agrees
pretty close to the URL you posted.  It is not clear
if that one has any diffraction correction.  I made
this sheet in response to questions about UHF
controlled UAVs my son is designing.
    Looks like about 9-10 miles for a bouy to a 30'
station...ignoring any ducting of course.  Would make
an interesting experiment, though.  You might hit a
satellite at times, but 300mw. sounds pretty thin.

73, Steve, K9DCI--- "Jan T. Pharo" <la2bba at jpharo.net>

> "Richard Amirault" <ramirault at verizon.net>, Mon, 10
> Sep 2007 15:23:06
> -0400:
> >No one seems to have noticed my comment on limited
> distance of line of sight 
> >due to curvature of the earth.[...snip...]
> In eyeheight from a small craft (where you stand
> with the feet approximately at sea level) we learnt
in my boating course that I'd have the horizon about 3
nautical miles away (and the web site mentioned above
tell me the same). It might be a good idea to build
the buoy so the antenna is as high above the water
> as possible, in order to increase the distance to
the horizon (and possibly reach a digipeater on a
tower ashore)
> -- 
> 73 de Jan, LA2BBA
> Hvaler, Norway
> _______________________________________________
> aprssig mailing list
> aprssig at lists.tapr.org

Shape Yahoo! in your own image.  Join our Network Research Panel today!   http://surveylink.yahoo.com/gmrs/yahoo_panel_invite.asp?a=7 

-------------- next part --------------
A non-text attachment was scrubbed...
Name: Line of sight calc.xls
Type: application/vnd.ms-excel
Size: 20992 bytes
Desc: 3533897820-Line of sight calc.xls
Url : http://www.tapr.org/pipermail/aprssig/attachments/20070910/91c7c23d/attachment.xls 

More information about the aprssig mailing list