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Analog Mux breakdown
Sens 4 is know to be capacitive since it is listed as such on page 13 of the [https://web.archive.org/web/20200619153019/https://www.wmo.int/pages/prog/www/WMOCodes/WMO306_vI2/LatestVERSION/WMO306_vI2_CommonTable_en.pdf WMO Common Code Tables Document]
== Test Points ==
TP58 - MUX in/out (U14 Pin 3)
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==Circuits==
===Relative Humidity Circuit===
[[File:Relative Humidity Circuit Schematic.pdf|thumb|Relative Humidity Circuit Schematic]]
U16 -Input also has a cap to ground not shown on the sketch. <br /> === Analog Multiplexer ===U14 is an 8-channel mux/demux. Four of the channels (A0-A3) go to SP1. (A4-A7 appear to go to SENS2-4, need to be traced) Pin 3 is the common in/out, and goes to R13 (560k) and R15 (47k). R15 goes to U15 Pin 7 (555 Reset), and R13 goes to U15 Pin 8 (555 Control.) <br />
==Modifications==
