## Appendix A  
Detailed list of the components.  
1. [leftmargin=*]
2. Amphenol NTC thermistor MC65 series, 10K 25 \({}^{\circ}\)C is a precision solid state temperature sensor. The tolerance and interchangeability of this sensor is \(\pm\)0.05 \({}^{\circ}\)C. It is resin coated for good mechanical strength and resistance to solvents. The sensor itself is a 1.65 mm diameter \"point\"-sensor with 0.1 mm diameter heavy isomid insulated bifilar nickel lead wires. Its thermal time constant is 0.5 s in stirred oil an d8 s in still air. The datasheet is available in the reference [24].
3. Metal Film Resistor Vishay/Dale [47]. Through Hole 1/4-watt 10 Kohms with 0.05% tolerance and 5 ppm.
4. Metal Film Resistor Vishay/Dale [47]. Through Hole 1/4-watt 10 Kohms 0.1% tolerance 5 ppm.
5. Amphenol Industrial Temperature Sensor JS8746A [25]. The tolerance and interchangeability of this sensor is \(\pm\)0.15 \({}^{\circ}\)C. According to the manufacture notes [21] the sensor has been designed to address all aspects of temperature measurement for HVAC (Heating, Ventilation and air conditioning) control systems. Employing materials and build standards that enhance the sensor's ability to withstand water ingression and degradation, the sensor meets statutory requirements for temperature measurement and performance expectations. It is equipped with environmental protection IP68, it is resistant to salt solutions, ozone, UV and a variety of marine environment cleaning detergents. It is equipped with stainless steel hard shell, with class corrosion resistance A2 or better according to ISO3506.
6. Precision LM4040 Voltage Reference Breakout 2048 V and 4096 V [27]. This breakout was used due to the noisy voltage reference of the adafruit feather 32u4. To achieve high precision, we used the breakout to have a reference of 2048 V for the thermistors. Using Ohm's Law, the reference had to be stable as possible to calculate the temperature with high precision and accuracy.
7. ADS1115 16-bit ADC-4 channels with Programmable Gain Amplifier [26]. This part was used due to the lack of the feather's 32u4 precision in the conversion of analog to digital signal. The feather has a 10-bit precision ADC, so we used this part to reach a 16-bit ADC for the system to be more sensitive to small changes of the voltage. For that reason, the system can be more precise. Moreover, we used the amplifier of the part to amplify the signal. We kept the amplification factor low to make the noise as low as possible.
* Adafruit Feather 32u4 Basic Proto [23]. We used this development board because the microcontroller has proven to be robust and tested for many years since it was released. The MCU is clocked at 8 Mhz and at 3.3 V logic. It has a built-in USB-to-serial program and debug capability built in. Additionally, it is a low consumption microcontroller and the board is equipped with a connector for any 3.7 Lithium Polymer battery and built in charging.
* Adafruit Adadogger FeatherWing [29]. This shield is equipped with an SD-card module and a battery-packed Real Time Clock. It can be plugged on top of the microcontroller board and can be easily used.
* Lithium Polymer single cell 3.7 Volt and a capacity of 1200 mah.
* A switch waterproof cap [48].
* Cable Glands pg7 [49].
* An IP 54 box by HAMMOND [50].
* Heat-Shrinkable tubes, 3 mm and 0.8 mm.
* Prototyping hook-up single wires 22 AWG.
* Double-Side Printed Circuit Board.
* Radiation shield. A custom-made radiation shield made of plastic was design and constructed using CNC machinery.