https://en.wikipedia.org/wiki/Software-defined_radio
I rest my case, a 7200 is not an SDR.
Quoting:
"Software-defined radio (SDR) is a radio communication system where components that have been typically implemented in hardware (e.g. mixers, filters, amplifiers, modulators/demodulators, detectors, etc.) are instead implemented by means of software on a personal computer or embedded system.[1] "
Well, without jumping into how-many-angels-on-head-of-pin argument, and without conceding final authority to Wikipedia, I'll say the SDR is a loose term and people apply it rather loosely.
If I were being pedantic, I might say a radio is DIGITAL if it does most of its business in the digital domain. But even that can only ever be a matter of degree. There was a time not long ago when people would say, well, yeah, there's an analog mixer up front but after that it's ADC and all digital, and that's a digital radio. When there was no digital circuit that could keep up with RF at frequency, that seemed pretty reasonable. Now, people might say, well, it's only an all-digital radio if it has the ADC right after the antenna. But what about pre-selectors and antialiasing filters? Those are analog. So, obviously, no radio will ever be 100% digital.
Then there is the question of _software_. Clearly a lot of digital radios are not software defined, they run special purpose hardware blocks, or maybe they run in an FPGA. Hey, FPGAs are kind of interesting. You start with something that looks a lot like software (verilog, vhdl) and through various processes end up with a bitstream (also looks like software) that is stored in memory and loaded into the fpga when it starts. Maybe that IS software defined?
Or maybe the hardware block that does the digital business is actually just a special purpose DSP, deeply embedded in some ASIC, running a piece of software that you will never directly access or see? Is that SDR?
To me, the holy grail of SDR would be a very open radio (FPGA or DSP based or combo) that I could radically change the data flow of with my own efforts: either providing DSP code or re-zapping the FPGA. Even now, with almost every radio with a DSP in it, it would be super duper nifty if I could, say: at this point in the data stream, use the array of filter coefficients found on my SD card to implement a FIR. Such could be implemented in a digital non-SDR, but I don't care. It would still be cool.
In fact, if you use GNUradio and similar with these "SDR sticks" you are doing SDR. I'd just like to see that ability in a radio that could also stand alone. That would be nifty, and you could call it whatever you like. :-)