... | ... | @@ -26,7 +26,7 @@ capacitors around the operational amplifier. We used a combination of |
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inputs to do the
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job.
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![](/uploads/b0ba733fb34ff727efbf1aafdbcfef22/filter.png)
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![](https://ohwr.org/project/r19-tdc-del-a/uploads/b0ba733fb34ff727efbf1aafdbcfef22/filter.png)
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*Figure 1 - Filter schematics*
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The capacitor C1 is used to realise a high-pass with the rest of the
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... | ... | @@ -68,7 +68,7 @@ Unfortunatelly, this saturates the ADC. As its recovery time is |
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relatively long, the non linearities decrease the
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precision.
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![](/uploads/e5208ef5c1f2245a5641234f6d7cc887/pulseBeginning.PNG)
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![](https://ohwr.org/project/r19-tdc-del-a/uploads/e5208ef5c1f2245a5641234f6d7cc887/pulseBeginning.PNG)
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*Figure 2 - Distorrtion at the beginning of the pulse. Resolution is
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20ns/DIV on the x axis and 227 mV/DIV on the y axis*
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... | ... | @@ -78,8 +78,8 @@ Figure 2 presents two other filters that could be used instead of the |
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actual
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one.
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![](/uploads/487db09f2d75e3fed85c1087b93a02c7/filter2.PNG)
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![](/uploads/1602e1b579ab9f27f4c00dcc1ed0ddcd/filter3.PNG)
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![](https://ohwr.org/project/r19-tdc-del-a/uploads/487db09f2d75e3fed85c1087b93a02c7/filter2.PNG)
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![](https://ohwr.org/project/r19-tdc-del-a/uploads/1602e1b579ab9f27f4c00dcc1ed0ddcd/filter3.PNG)
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*Figure 2 - Other possible filters*
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