Right - sorry. But, then we do have an analog capacitive sensor.

According to 
http://www.wxforum.net/index.php?topic=33534.msg340277#msg340277 we're 
dealing with a sensor that precedes this one: 
https://www.newark.com/vishay-bc-components/2322-691-90001/humidity-sensor/dp/89F5822

They have apparently identical specs. On the second link there's a PDF with 
specs for the part. They don't state curve details, though.

On Friday, March 29, 2019 at 9:36:44 PM UTC+1, [email protected] wrote:
>
> On Friday, 29 March 2019 17:28:47 UTC-3, kobuki wrote:
>>
>> But if I'm right, temps should also be wrong. For the NTC Davis is using 
>> we already have the formula IIRC. 
>>
>
> Kobuki,
>
> You are wrong! :-) The analog temperatures are calculated right, see code 
> below:
>
> ============================================================
> elif message_type == 8:
> # outside temperature
> # message examples:
> # 80 00 00 33 8D 00 25 11 (digital temp)
> # 81 00 00 59 45 00 A3 E6 (analog temp)
> # 81 00 DB FF C3 00 AB F8 (no sensor)
> temp_raw = (pkt[3] << 4) + (pkt[4] >> 4)  # 12-bits temp value
> if temp_raw != 0xFFC:
> if pkt[4] & 0x8:
> # digital temp sensor
> temp_f = temp_raw / 10.0
> temp_c = weewx.wxformulas.FtoC(temp_f) # C
> dbg_parse(2, "digital temp_raw=0x%03x temp_f=%s temp_c=%s"
>   % (temp_raw, temp_f, temp_c))
> else:
> # analog sensor (thermistor)
> temp_raw /= 4  # 10-bits temp value
> temp_c = calculate_thermistor_temp(temp_raw)
> dbg_parse(2, "thermistor temp_raw=0x%03x temp_c=%s"
>   % (temp_raw, temp_c))
> if data['channel'] == th1_ch:
> data['temp_1'] = temp_c
> elif data['channel'] == th2_ch:
> data['temp_2'] = temp_c
> else:
> data['temperature'] = temp_c
> ============================================================
>  
> The formula of the humidity I didn't know. Probably my formula wont work 
> then...
>
> Luc
>

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