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Hello All,<br>
<br>
Many people are aware that Foxtrak trackers are not decoded reliably
by certain Argent Data devices (eg current versions of Open Tracker
3, Open Tracker USB on my tests).<br>
<br>
It seems that the underlying issue is that the DSP based decoder
used in current versions of those products is not tolerant of the
modulation generated by the Foxtrak (whereas all of the TNCs I have
tested decoded Foxtrak just fine).<br>
<br>
Exploring the issue more widely, the same problem exists with not
only the default firmware by DK7IN, but also original TinyTrak v1
firmware and aprstraker v0.11.<br>
<br>
Before you dismiss this as an issue for Foxtrak hardware...<br>
<br>
I have conducted comparative tests of a genuine TinyTrack3+ and
Foxtrak both fitted with TT3+ v1.42 firmware, and can report that
they are both decoded well, and equally well by VK2RHR-1 which is an
Open Tracker 3.<br>
<br>
There are two messages from all of this:<br>
<ul>
<li>if you operate a digi, select equipment that reliably decodes
most of the common trackers etc, and equipment that uses DSP
decoding requires more careful evaluation than that which uses
traditional modem chips;</li>
<li>if you operate a tracker and want it to be decoded by most
digis and iGates, choose equipment compatible with existing
infrastructure (which includes a lot of Argent Data devices).</li>
</ul>
A possible solution for owners of Foxtraks and early TinyTrackers
might be to upgrade the chip or whole device to TT3+ v1.42 (which is
better in a whole lot of respects).<br>
<br>
Note that I have not tested TT3+ with DSP based decoders other than
Argent, so I cannot comment on compatibility for instance with
Microsat (which are used in Australia). Perhaps hams using those
systems can share their experience.<br>
<br>
In researching the topic, it became clear that the manufacturers of
DSP based decoders appear to not perform interoperability testing
with other brand products... the buyer must do it!<br>
<br>
73<br>
Owen<br>
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