Good SDRs have overwhelmingly better performance than all but the most expensive traditional superhet receivers. Even then, the exotic superhet receivers match rather than beat equivalent SDRs. Direct conversion receivers are exceptionally good at isolating weak signals that are close in frequency to strong signals, which is a particularly important trait in amateur radio operation. This is widely understood and largely uncontroversial.
Some amateur SDRs are essentially computer peripherals, but they increasingly look just like traditional transceivers. The Icom IC-7300 was the most talked-about transceiver of 2016; It operates like a traditional transceiver and costs about the same, but has exceptional receiver performance and a host of DSP-based bells and whistles. I expect that many Elecraft customers are completely unaware that they bought an SDR rather than an analog transceiver.
Personally, I would never go back to a superhet receiver. If you use a good SDR for half an hour, you're spoiled for life. Superhet receivers still have a place at the low-end of the market, but they're being slowly squeezed out.
Except for noise. Computers are noisy beasts with spurious radiation (birdies) from DC to UHF. Trying to run a sensitive receiver anywhere near a computer, means that you have to put up with an unholy amount of interference. And nothing in the design of the SDR can fix this.
Old-time hams would never have a computer in the same room as their radios because of this interference.
FWIW, I was designing and building my own SDRs ten years ago, and am currently running one of the high-end SDRs.
As above, I have a RF Space NetSDR+ which is connected to the computer via ethernet. So you can remote it via WiFi or any similar networking technique.
>Are there SDRs where you "remote" the receiver and antenna?
Yes. The FlexRadio and Apache Labs SDRs are equipped with ethernet. There are numerous standalone SDRs that can be used without a computer.
The rtl-sdr isn't really comparable to a proper radio. It is, after all, just a repurposed TV tuner. It's a great little toy for exploring radio, but the performance is exactly what you'd expect for a $20 dongle.
I've used rtl_tcp on a raspberry pi before, but that was mostly to get the receiver close to the transmitter (in which case I unhooked the antenna as well).
It all boils down to shielding. A Rigol spectrum analyzer will never have the performance of an HP due to the lack of EMI mitigation. I have a Flex 6500 with no noise issues due to the computer, then again my RX antenna is 100 feet away.
Yeah. But I don't think your Flex 6500 tunes above 70MHz, which is where the birdies from modern computers, modems, video cards, and high-end displays are worst.
I have a RF Space NetSDR+, and it's wonderful below about 30 Mhz, but there's a horrifying racket on 6m and 2m, and the FM broadcast band is pretty much unusable for weak signal work.
I'm playing with a optical link to the top of the hill behind my place. We shall see.
I'm surprised that the computer interference issue isn't more widely discussed. I suspect that it's because newbies have no idea of how much of the junk they see on their screens doesn't actually exist. Plus living in city environments they are so swamped by RFI that they think it is normal.
Just looking at the screen on the OP's web page makes me shudder. It's a whole mess of computer interference.
Some amateur SDRs are essentially computer peripherals, but they increasingly look just like traditional transceivers. The Icom IC-7300 was the most talked-about transceiver of 2016; It operates like a traditional transceiver and costs about the same, but has exceptional receiver performance and a host of DSP-based bells and whistles. I expect that many Elecraft customers are completely unaware that they bought an SDR rather than an analog transceiver.
Personally, I would never go back to a superhet receiver. If you use a good SDR for half an hour, you're spoiled for life. Superhet receivers still have a place at the low-end of the market, but they're being slowly squeezed out.