In message <Pine.LNX.4.64.1203152001370.3542@tesla>, Marek Peca writes:
>Yes, it should work on any USB audio capable OS, ie. Linux, Windows, MacOS etc. I would like to recommend against this approach for a number of reasons. First, yes, while you can do undersampling and such, it puts very high requirements on your analog filters. The reason I use 1MSPS is that it allows me to use a very sloppy low-pass filter filter which just cuts off somewhere around 150-200 kHz, and do everything else in software. This means that I have no phase/group-delay distortion in the analog part that I need to compensate in software. It also means that I don't have to change hardware to play with different signals, they're all there, all the time, for instance the stuff under http://phk.freebsd.dk/Leap/ is pulled out that way. If I, based on my design, were to design a gadget for doing VLF time-nuts stuff, it would be: Floating Input trafo with center-tap for powering antenna 16 bit 1MSPS ADC ARM chip 10MHz clock input 1PPS sync input 1PPS sync output (DAC output for {Rb|Ocxo}DO use ?) 1-4MB RAM USB2 interface Sending 2MB/s through a serial port profile is not a big problem for USB2 or for that matter for an operating system, so you can easily grap full spectrum and play with your your PC, and once you have made some of it work, you can compile the same code and and download it to the ARM chip, and use the serial port only for stats/summary/(Tek4010-graphs) or you can use another USB profile or whatever. The ARM chip is plenty powerful to do pretty much anything you are to on its own once you give it the code to do so. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.