|
1-Wire Humidity Sensor: App Note 758: Maxim IC
(application note added6/06) |
|
741 Based Light Sensor: CdS photocell used for light/dark
controlled relay (added 4/02) |
|
AN-256: Circuitry for Inexpensive Relative Humidity Measurement: National
Semiconductor Application Note (app note added 2/06) |
|
AN-829: Environmental Compensation on the AD7142: The Effects of Temperature and
Humidity on Capacitance Sensors: AN-829 Analog Devices Application Notes (app note added 6/06) |
|
Circuit Tests Power
Outage Susceptibility: 03/03/97 EDN-Design Ideas / (added 3/03) |
|
Dew sensor: Dew (condensed moisture) adversely affects the normal
performance of sensitive electronic devices. A low-cost circuit described here can be used to switch off any gadget automatically in case of
excessive humidity. At the heart of the circuit is an inexpensive (resistor type) dew sensor element. Although dew sensor elements are widely
used in video cassette players and recorders, these may not be easily available in local market. However, the same can be procured from....
(added 10/05) |
|
Environmental Compensation on the AD7143: AN-829 Analog Devices
Application Notes (app note added 6/06) |
|
Low cost relative humidity Transmitter uses single logic IC:
11/08/01 EDN Design Ideas / (added 1/05) The low-cost percentage-relative-humidity radio transmitter in Figure 1 operates in
a cold-storage warehouse for vegetable storage at temperatures of 1 to 5 C. It is generally difficult to collect such data from a
low-temperature area with high humidity and low illumination. The transmitter design is simple: It uses a readily available, capacitor-type
percentage-relative-humidity se... ... |
|
Measure humidity and temperature on one TTL line:
08/30/01 EDN Design Ideas / (added 1/05) By combining the responses of an Analog Devices (www.analog.com) AD590 temperature
sensor and a Humirel (www.humirel.com) HS1101 humidity sensor, you can generate a single TTL-level signal containing information from both
sensors (Figure 1). This design uses a 74HC123 monostable multivibrator, IC1, to form a free-running oscillator. ... |
|
Remote humidity sensor needs no Battery: 04/04/02 EDN
Design Ideas / (added 1/05) Using ac-line power sources and batteries for remote humidity sensors is undesirable because
these sources can be troublesome if you mount them in inaccessible points, such as smokestacks, cold-storage chambers, or darkrooms, where
maintenance is difficult and inconvenient. Figure 1 shows a simple way to remove the power source from the humidity-sensor circuit. ... |
|
Signal Conditioning Precisely indicates Humidity: 02/02/98 EDN-Design Ideas / (added 4/02) The circuit in Figure 1 translates the
level of humidity from 0 to 100% into a stable, respective dc signal of 0 to 100 mV. The heart of the circuit is IC1, the IH3602-C
relative-humidity sensor (Microswitch/HyCal Sensing Products, Freeport, IL). This device operates on 5V at 200 mA and provides a dc output of
0.8 to 4.0V .... |
|
Tiny Dew Sensor: (electronic Circuit / Schematic added 10/04) |
|
Transmitter senses triple relative humidity figures:
09/26/02 EDN Design Ideas / (added 1/05) The circuit in Figure 1 is a triple, relative-humidity sensor and radio
transmitter. Sensors 1 and 2 form two gated oscillators with natural frequencies of 10 and 5 kHz, respectively, at relative humidity of 50%.
The gated oscillators use variable resistances R2 and R3, respectively. Together, these two oscillators generate FSK-modulated outputs at
output of IC1B, Pin 6.... |
