I heard a program on NPR yesterday about a bunch of scientists using trackers on birds. He said they use a store and forward method using a cell fone chip to dump a days worth of data in a text message to the scientist. It sounded like they were battery powered and used a GPS chip like we do,
He mentioned the trackers were about the size of a matchbook so I am guessing the birds they are tracking are large, like geese or large seabirds.
Brian K9WIS
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From: "Ken Daniel via groups.io"
To:
[email protected]Cc:
Sent: Tuesday March 30 2021 7:12:57PM
Subject: Re: [HABalloon] Unable to Decode WSPR Generated by SI5351 Project
Hi Mikael,
?
I have a lot of experience using Si5351 on a
breadboard using Adafruit and Amazon versions.? I even though
the frequency of the crystal and transmit frequency is set
correctly the signal is typically out of band.? This is due to
the inaccuracy of the crystal.? The width of the band is only
200 Hz.? In the past I have had to fudge the transmit
frequency to bring it into the band.? Typically the SI 5351
has two 3 inch pieces of wire for an antenna.? I use a
standard ham setup for 20 m to receive it e.g. transmitter and
tuned up antenna.
?
When I power using the usb from a desktop
computer, I get a lot of spike side bands that are easy to
see.
?
Ken
K9YO
