Matti Aarnio's (OH2MQK) ham pages..

SDR DSP components

Earlier I was looking for a way to have a high-quality sound-card with excellent noise properties, and high-quality (precission) clock. Since then it has grown to include the host computer, as Analog's Blackfin DSP can run Linux, and there are versions with 100 Mbps Ethernet builtin.

Current plan is:

The SDR-DSP-3:

This card can run stand-alone (uC)linux, and do fancy things all by itself, but it can also be used in dummy mode to act as remote audio card.




The digital upconverter has a problem of not being quite compatible with DSP I²S (S-Port) protocol, and thus needs some glue logic...

In quadratude mode the AD9874 outputs a load sync pulse, but of course not anything suitable for serial clock of I²S. PLL multiplication of load pulse is an option, but required dynamic range of the frequency is rather large...

Possibility is to use "multichannel framing"..

On mezzanine cards (those SPORT slots), various ideas:

Eagle CAD material at:


Other somewhat related (or not) things