Topband: Web-connected receivers/real benefits of SDR technology

[Steve Ireland]

G'day all

 

It is very interesting (and sad) to read the emails from Thor TF4M and
Brendan EI6IZ about how some have misused their web-connected receivers.
Note that I used the term 'web-connected receiver' rather than SDR.  What a
disappointment that the access privileges kindly granted by these amateurs
(and others) to their receivers, which are connected to really well-designed
and performing antennas, are being misused by some in order to cheat and
unethically boost their QSO/DXCC totals.   

 

As a long-standing proponent of SDR (software defined receiver) technology
versus conventional superheterodyne technology, I think it is important to
make the distinction between the fact that these receivers just happen to
use SDR architecture and the fact that they are web-connected.  It is the
fact that these receivers can be accessed via the web that makes them open
to misuse, not simply because they use SDR technology. 

 

The reason that I am making this simple but obvious point is because there
are a small but vocal minority of radio amateurs who seem to regard anyone
who uses SDR technology as somehow likely to push the ethical boundaries in
how they use it - a perception that makes me disappointed and annoyed.   

 

For some time I used a Mercury HPSDR (digital down conversion) receiver and
found it could resolve weak CW and SSB signals in noise that my (fantastic)
Elecraft K3 superheterodyne cannot, owing to the latter's use of crystal
filtering which means that noise pulses are distorted by the filtering and
thus render weak signals harder to understand than on a SDR receiver that
uses purely digital filtering.

 

This SDR technology is ideal for 160m operation (just ask Greg ZL3IX, who is
one of the few topbanders who use a SDR digital down conversion/up
conversion transceiver, which he has built himself).  It would be shame that
this technology gets a bad name owing to its ability to be web-connected,
when it particularly lends itself to weak-signal low-band operation and can
offer some real relief for those topbanders who are noise-inflicted.

 

Vy 73

 

Steve, VK6VZ

(Joint author with VK6APH of the Software Defined Radio section of 9th/10th
editions of the RSGB's Radio Communication Handbook)