A  SIMPLE, ACCURATE,  AND IN-EXPENSIVE TEMPERATURE SENSOR

                                WITH COMPUTER  MONITORING

 

Need a Simple, calibrated temperature sensor you can monitor on your computer?  

 

Uses include:

 

1.  Linear Amplifier Temperature Monitor (Mount in exhaust airflow or adjacent to finals)

2.  Heatsink temperature sensor.   

3.  Room/ Outdoor Temperature.

4.  Remote Monitoring of equipment Temperature.

 

The   LM34 output is 10 millivolt/ degree Fahrenheit.

          LM35 output is 10 millivolt/degree Centigrade.

 

You can use either sensor for this project, they require no calibration and are accurate +/- 1.5 degree. 

Cost is approximately $1.60.   Use a 2-conductor shielded cable between the sensor and the WN-1

PC board connector to keep RF out of the system.  Solder C1, C2 and R2 directly to the pins of the

LM34/35.   Solder R3 and C3 directly to the pins of J5.   You can add up to four temperature sensors

to your WN-1 system using the four auxiliary analog inputs.   Sensors are available in TO92 from

Digikey or Allied Electronics (See the "Links" page).  

 

 

 

 

 

Instructions:

 

   Solder C1, C2 and R2 directly to the pins of the temperature sensor.   Solder the 2-conductor cable to the circuit. 

You can cover the sensor with Silicone to protect it from moisture if you want.  Add a piece of tubing over the

 sensor to protect it. 

 

    Solder R3 and C3 to the cable end and to J5.  You can use a 3-pin connector in one of the rear panel holes so

you easily unplug the cable from the unit.  A small stereo headphone jack will work fine.  From the stereo jack

solder a wire to pins 5, 9 and 15, as shown.  

 

    Go to the Configuration software menu on your Wavenode software:

      Set the vertical scale on Auxiliary Meter #1 for 200 if using a Fahrenheit sensor.   Set it to 100 if using the

         Centigrade version.

      Set the Vertical label on this meter to "Degrees".    

      Set the Scale Factor to 100.  

      You will now have a 0-200 F. meter (or 0-100 degree C). Your thermometer will read out directly in degrees C

         or degrees F.

 

    If you notice intermittent operation when transmitting, you may have to put a ferrite core at each end of your shielded

cable.