> Suitcase SETI [...] was a little portable apparatus..[...] 1980s technology. Here's a dual Fourier processor. Look at that. It's a whole rack. And it's got a couple of 68000s cranking away doing 128k FFTs, and here's a machine actually running Unix. In 1980, that was pretty hot stuff, portable computer. It was made by a company called WICAT that you've never heard of. That's the World Institute for Computer Aided Teaching. And here's a little video cassette recorder. We put all our data on that. Anyway, here's the box of the Fourier transformers. It's a bunch of 16k memory chips here. There's a whole wire wrapped on the back. Here's your 68000 here. Here's a 16 by 16 multiplier. These things cost a few hundred dollars back then. This is expensive stuff.
> We need more channels. So we built a thing called BETA [...] It must have been Unix. Linux? I don't know. Something. So here's our rackets. We're down to one rack now, and we actually have lots of bytes. And here's a whole bunch of 90-megahertz Pentium PCs. That was state of the art back then, and we cobbled these things all together. And here's what one rack looked like. So it's now the billion-channel extraterrestrial assay. It no longer brags about being a supercomputer. We learned our lesson from that one. So that's what we did, and this thing was able to search the full water hole. [...] We were sort of proud of how fast this thing produces data. Two seconds of data would fill up a CD, which was state of the art optical storage in those days.
> Let's build an all sky optical SETI. [...] he came up with a really clever idea [...] if you take a fancy FPGA, one of these Xilinx parts, they have a whole bunch of inputs which are meant for digital signals, they're LVDS differential pairs. But they're very good comparators, so you can trick it into being a flash analog to digital converter, even though it doesn't know that's what you're doing. So you tie eight of these with a common signal, and put in a progression of biases, and you've got yourself an ADC. And you can run these things at 1 and 1/2 giga samples per second. And you can put 32 of these into one chip
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