VHF weather imaging using Automatic Picture Transmission (APT) is still very much alive and operational both on NOAA and EUMETSAT birds despite the desire of the weathermen for ever greater bandwidths on 1.6GHz and above. It doesn't appear to improve their forecasting however.......
Paul Reeves, G8GJA -----Original Message----- From: Lux, Jim (337C) [mailto:[email protected]] Sent: 15 August 2009 23:34 To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Difference in GPS antennas On 8/15/09 3:25 PM, "Chuck Harris" <[email protected]> wrote: > Lux, Jim (337C) wrote: >> >> >> On 8/15/09 8:27 AM, "Magnus Danielson" <[email protected]> wrote: >> >> >>>> If you're near a harbor with fishing boats, you'll see plenty of quad >>>> helices about a half a meter in overall height, used for VHF Weather >>>> satellite reception. They're also used on spacecraft (Mars Science Lander, >>>> Mars Reconnaissance Orbiter, and Phoenix all have UHF quad helix antennas, >>>> I >>>> think, for about 400 MHz) >>> Not used by the fishing vesels near me... >> >> Really? Practically all the fishing boats (mostly squid) boats going out >> from Ventura Harbor (in Southern California) have big ol' quad helix >> antennas up on the cross bar (as well as the usual HF SSB and VHF whips and >> the radar). Maybe it's a regional preference thing (or folks are going to >> the 1.6 GHz band or something). > > Haven't all of the VHF weather satellites been decommissioned? Could be. I suspect that those antennas have been up on those boats for decades. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. This email, including any attachment, is a confidential communication intended solely for the use of the individual or entity to whom it is addressed. It contains information which is private and may be proprietary or covered by legal professional privilege. If you have received this email in error, please notify the sender upon receipt, and immediately delete it from your system. Anything contained in this email that is not connected with the businesses of this company is neither endorsed by nor is the liability of this company. Whilst we have taken reasonable precautions to ensure that any attachment to this email has been swept for viruses, we cannot accept liability for any damage sustained as a result of software viruses, and would advise that you carry out your own virus checks before opening any attachment. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
