From 80361fcd58494108aa5678859398636782e568a6 Mon Sep 17 00:00:00 2001 From: wb4jfi Date: Tue, 10 May 2011 17:49:14 -0400 Subject: [PATCH 1/1] --- projects/dsp.mdwn | 1 + 1 file changed, 1 insertion(+) 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. -- 1.7.9.5