3 ms·
SDRs are total spur-fests, yes, but at 0% the cost of a real SA (rounded) the economics sometimes work out :-) That said, at the high end of the SDR range, the
by jjoonathan 8y ago
SDRs are total spur-fests, yes, but at 0% the cost of a real SA (rounded) the economics sometimes work out :-)
That said, at the high end of the SDR range, the new AD937x chips ($325 in qty 1k!) make impressive claims wrt automagic spur suppression. They still don't beat high-IF or YIG preselected SAs, but now they claim to be in the ballpark under non-overload conditions. Has anyone here dug deep enough to comment?
- madengr 8y agoThe pre-selection is a big deal. The AD936x needs good front end filtering to reject n*LO. For instance 5x146 MHz = 730 MHz, which translates that 730 MHz nation-wide LTE signal smack-dab into the 2m amateur band. Unless they have a new front-end architecture in the AD937x, all the I/Q calibration won't help them. Of course as you said, for $325 it's not a consumer chip, so some $ will be spent on external passives.
- jjoonathan 8y agoAh, right, I/Q calibration can't suppress anything out-of-band. Makes sense.