[TenTec] What's an SDR?

[Martin AA6E]

OK, I'll bite.  BQF says Orion is not an "SDR", but
many other people do use that term for our favorite
big black box.  I have wondered about this.

A "software defined radio", we are told, is one where
the analog signal is sampled as close to the antenna
input as practical.  From then on, filtering and
detection are done in software - or firmware or DSPs
if you like.

The Orion uses conventional local oscillators and IF
filters.  The third IF, at 14 kHz, is sampled, and
filtering and detection are "software".  So we have a
14 kHz SDR, at least.

Whether the Orion is really an "SDR" is a semantic
issue.  It's probably not yet quite practical
(economical) to sample at the antenna input jack. 
Some analog filtering, amplification, and conversion
is needed.  Orion has quite a bit. 

Whatever else it is, Orion is enough of an SDR to be
totally reliant on its Sharc DSPs, its Dragonball, and
its firmware, for better or worse. 
 
I still have my TS-520S, just in case.

73, Martin AA6E


--- Tommy <aldermant at alltel.net> wrote:

> 
> I'm not sure why John is referring to the Orion and
> Jupiter as an 
> SDR, as they certainly are not.
> 
> Tom - W4BQF