X-Git-Url: http://amrad.org/gitweb/?p=amrad.git;a=blobdiff_plain;f=projects%2Fdsp.mdwn;h=a3d2295498682059ff0c9dab3733d6b067e12933;hp=aa326856125b1858897b4b5e68fc55f09a3bbd73;hb=80361fcd58494108aa5678859398636782e568a6;hpb=062b28ba9f2ad9ef019572d67e07895b0e5fc248 diff --git a/projects/dsp.mdwn b/projects/dsp.mdwn index aa32685..a3d2295 100644 --- a/projects/dsp.mdwn +++ b/projects/dsp.mdwn @@ -7,6 +7,7 @@ This page supports both SDR and DSP work. Terry, WB4JFI #SDR WORK --- +##CHARLESTON SDR RECEIVER #1 ##NEW MASTER OSCILLATOR FIXES PHASE NOISE (JAN.2011) I replaced the original program-once 76.8MHz master oscillator with a custom Silicon Laboratories SI570, programmed for 76.8MHz. The new oscillator dramatically reduced the phase-noise related artifacts when stronger signals hit the Charleston Receiver board. This SI570 can be ordered directly from SI Labs, at a cost of about $13 each, but I recommend group buys. The SI Labs part number is: 570CAC000729DG. In order to have access to the extra I2C program pins (not absolutely required), I placed my SI570 on top of four zero-ohm SMT resistors, that act as spacers between the board and the SI570 itself.