README: doc postfilter

Fixes Gitea issue #21
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Astro 2020-12-16 20:47:18 +01:00
parent dc41473493
commit 93ea46d512
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@ -157,6 +157,18 @@ Set the Beta parameter:
s-h 0 b 3800
```
### 50 Hz filtering
The AD7172-2 ADC on the SENS inputs supports simultaneous rejection of
50 Hz ± 1 Hz and 60 Hz ± 1 Hz (dB). Affecting sampling rate, the
postfilter rate can be tuned with the `postfilter` command.
| Postfilter rate | Rejection | Effective sampling rate |
| --- | :---: | --- |
| 16.67 Hz | 92 dB | 8.4 Hz |
| 20 Hz | 86 dB | 9.1 Hz |
| 21.25 Hz | 62 dB | 10 Hz |
| 27 Hz | 47 dB | 10.41 Hz |
## Thermo-Electric Cooling (TEC)