precision_timing:thunderbolt_damping [KO4BB Wiki]

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+====== Trimble Thunderbolt Damping ======
+Tbolt users,
+One of the questions I often hear is what should the Tbolt's Damping be set to?
+Assuming the Dac_Gain and TC_Sec are correctly set, then Damping is the easy one;
+) If your concerns are freq accuracy and you don't care about Phase accuracy, Set the damping from 1 to 1.5  with the Factory default of 1.2 being a good Nominal Value.
+) If your concerns are Phase accuracy and are willing to accept some increase in freq noise, Set the damping from 0.5 to 0.7  with  0.6 a good nominal value.
+) And for a compromise between both Phase and Freq Set the Damping from 0.7 to 1.0, with 0.85 a good nominal value.
+Lower damping settings < 1.0  are best used only with longer TC settings > 100
+The non technical description of what damping does (in the Tbolt) is:
+The TC setting is the Tbolt's Freq correction Time Constant  (short term Osc error) and the Damping setting effects the Tbolt's Phase correction time. ( Long term Phase error) The way that Damping controls Phase is by causing the Freq error correction to Overshoot.
+As to how much difference changing the damping makes.
+The difference in phase error between slow and fast damping setting can be 10 to 1 when the TC is set to the high value needed to get best freq noise.
+Hope this clears up some of the Damping setting questions.
+Here is the response with various TC and Damping settings
+{{:precision_timing:tbolt_damping.gif|}}
+Warren