Silicon ChipPM (particulate matter) ‘Dust’ Sensors - November 2023 SILICON CHIP
  1. Outer Front Cover
  2. Contents
  3. Subscriptions: PE Subscription
  4. Subscriptions
  5. Back Issues: Hare & Forbes Machineryhouse
  6. Publisher's Letter: Upping your electronics housing game
  7. Feature: Where’s my pneumatic car? by Max the Magnificent
  8. Feature: Net Work by Alan Winstanley
  9. Feature: The Fox Report by Barry Fox
  10. Project: LC Meter Mk3 by Charles Kosina
  11. Project: DC Supply Filter for vehicles by John Clarke
  12. Project: PM (particulate matter) ‘Dust’ Sensors by Jim Rowe
  13. Project: Anodising Aluminium at home by Phil Prosser
  14. Feature: Arduino Bootcamp – Part 11 by Max’s Cool Beans
  15. Feature: Circuit Surgery by Ian Bell
  16. Feature: AUDIO OUT by Jake Rothman
  17. Project: Electronic Building Blocks by Julian Edgar
  18. PCB Order Form
  19. Advertising Index

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Articles in this series:
  • (November 2020)
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  • Techno Talk (December 2020)
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  • Communing with nature (January 2022)
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  • Should we be worried? (February 2022)
  • Should we be worried? (February 2022)
  • How resilient is your lifeline? (March 2022)
  • How resilient is your lifeline? (March 2022)
  • Go eco, get ethical! (April 2022)
  • Go eco, get ethical! (April 2022)
  • From nano to bio (May 2022)
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  • Positivity follows the gloom (June 2022)
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  • Mixed menu (July 2022)
  • Mixed menu (July 2022)
  • Time for a total rethink? (August 2022)
  • Time for a total rethink? (August 2022)
  • What’s in a name? (September 2022)
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  • Forget leaves on the line! (October 2022)
  • Forget leaves on the line! (October 2022)
  • Giant Boost for Batteries (December 2022)
  • Giant Boost for Batteries (December 2022)
  • Raudive Voices Revisited (January 2023)
  • Raudive Voices Revisited (January 2023)
  • A thousand words (February 2023)
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  • It’s handover time (March 2023)
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  • AI, Robots, Horticulture and Agriculture (April 2023)
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  • Prophecy can be perplexing (May 2023)
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  • Technology comes in different shapes and sizes (June 2023)
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  • AI and robots – what could possibly go wrong? (July 2023)
  • AI and robots – what could possibly go wrong? (July 2023)
  • How long until we’re all out of work? (August 2023)
  • How long until we’re all out of work? (August 2023)
  • We both have truths, are mine the same as yours? (September 2023)
  • We both have truths, are mine the same as yours? (September 2023)
  • Holy Spheres, Batman! (October 2023)
  • Holy Spheres, Batman! (October 2023)
  • Where’s my pneumatic car? (November 2023)
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  • Good grief! (December 2023)
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  • Cheeky chiplets (January 2024)
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  • The Wibbly-Wobbly World of Quantum (March 2024)
  • The Wibbly-Wobbly World of Quantum (March 2024)
  • Techno Talk - Wait! What? Really? (April 2024)
  • Techno Talk - Wait! What? Really? (April 2024)
  • Techno Talk - One step closer to a dystopian abyss? (May 2024)
  • Techno Talk - One step closer to a dystopian abyss? (May 2024)
  • Techno Talk - Program that! (June 2024)
  • Techno Talk - Program that! (June 2024)
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  • Techno Talk - That makes so much sense! (August 2024)
  • Techno Talk - That makes so much sense! (August 2024)
  • Techno Talk - I don’t want to be a Norbert... (September 2024)
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  • Techno Talk - Sticking the landing (October 2024)
  • Techno Talk - Sticking the landing (October 2024)
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Items relevant to "Stewart of Reading":
  • Bookshelf Speaker Passive Crossover PCB [01101201] (AUD $10.00)
  • Bookshelf Speaker Subwoofer Active Crossover PCB [01101202] (AUD $7.50)
  • Bookshelf Speaker Passive and Active Crossover PCB patterns (PDF download) [01101201-2] (Free)
  • Bookshelf Speaker System timber and metal cutting diagrams (PDF download) (Panel Artwork, Free)
Articles in this series:
  • Easy-to-build Bookshelf Speaker System (January 2020)
  • Easy-to-build Bookshelf Speaker System (January 2020)
  • Building the new “bookshelf” stereo speakers, Pt 2 (February 2020)
  • Building the new “bookshelf” stereo speakers, Pt 2 (February 2020)
  • Building Subwoofers for our new “Bookshelf” Speakers (March 2020)
  • Building Subwoofers for our new “Bookshelf” Speakers (March 2020)
  • Stewart of Reading (October 2023)
  • Stewart of Reading (October 2023)
  • Stewart of Reading (November 2023)
  • Stewart of Reading (November 2023)
  • ETI BUNDLE (December 2023)
  • ETI BUNDLE (December 2023)
  • Active Subwoofer For Hi-Fi at Home (January 2024)
  • Active Subwoofer For Hi-Fi at Home (January 2024)
  • Active Subwoofer For Hi-Fi at Home (February 2024)
  • Active Subwoofer For Hi-Fi at Home (February 2024)
Using Electronic Modules with Jim Rowe PM (particulate matter) ‘Dust’ Sensors In this last article on low-cost air quality sensors, we look more closely at particulate matter (PM) sensors, also called ‘dust’ or ‘smoke’ sensors. A s mentioned in the first of these articles, PM sensors fall into three groups based on the size of the particles they are designed to detect: less than 10μm (PM10), less than 2.5μm (PM2.5) and less than 1μm (PM1.0). Currently, PM2.5 types are the most common in the low-cost section of the market, so we’ll concentrate on modules that support it. The basic principle of the most common type of PM sensor is shown in Fig.1. This was described in the first article but we’ll briefly go over it again. A small fan pulls air from the surrounding environment into a channel which passes through a sensing chamber. A laser sends a focused beam of light through the chamber, and any particles in the air scatter the light towards the sides of the chamber. One or more photodiodes detect this scattered light on the sides of the chamber. Any light not scattered by particles passes through the chamber to be absorbed by the ‘beam dump’. By controlling the fan speed and thus moving the air through the sensing chamber at a known rate of volume and measuring the photodiodes’ output, the concentration of particles in the air can be calculated. The result is in terms of μg/ m3 (micrograms per cubic metre), because the traditional and most accurate way of measuring PM is the ‘gravimetric’ method. This involves using a pre-weighed clean filter to collect particles from the air over a 24-hour sampling period, then weighing the filter again to determine the total mass of the accumulated particles in micrograms. The concentration is then obtained by dividing this figure by the total volume of air that passed through the filter during the 24-hour sampling period. Available PM modules There are several low-cost PM sensors currently available, including the Grove-Laser Sensor module, based on the Seeed Studio HM3301 sensor from Shenzhen, China, and the SN-GCJA5 sensor made by Panasonic Photo and Lighting Co in Osaka, Japan. The first is a fan-type sensor, as shown in Fig.1. But other types of PM sensor modules do not have an internal fan, including the Panasonic SN-GCJA5 and the XC3780 from Jaycar, based on the Sharp GP2Y1010AU sensor. We will look at all three of these sensor modules in this article. The Grove-Laser module The Seeed Studio HM3301 sensor comes inside a compact plastic and metal case measuring 38 × 40 × 15mm. In addition to the fan, laser and photodiodes, it has built-in electronics that provide fan control, The Grove-Laser air sensor module is based on the Seeed HM3301 particulate matter sensor. The sensor itself measures 38 x 40 x 15mm and the module comes with a suitable cable. Fig.1: the basic operating principle of a particular matter (PM) sensor. Air is drawn through a chamber with a laser beam, and any laser light scattered by particles in the air is picked up by one or more photodiodes. 30 Practical Electronics | November | 2023 External connections to the SN-GCJA5 sensor are via a tiny 5-way JST connector with 1.25mm pin spacing. No matching cable is supplied, which is a bit of a problem as they are hard to find! Fig.2: the components of the HM3301 sensor. The part at left is basically identical to what’s shown in Fig.1, while the section at right shows the electronics that pick up the scattered light level and turn it into a digital measurement. photodiode signal amplification, filtering, multi-channel data acquisition and an MCU (microcontroller unit) for data processing. The output is via a two-wire I2C serial interface. In the Grove-Laser module, the HM3301 sensor is mounted on a PCB measuring 80 × 40mm, with a fourpin connector at one end for connections to a 3.3-5V power supply and the I2C lines for connection to a PC or an external MCU. The effective PM2.5 measuring range of the module is 1-500μg/m3, although it can measure up to a maximum level of 1000μg/m3. This module is available from multiple online vendors from around £30-£40. Fig.2 shows a functional block diagram of what’s inside the HM3301 sensor. The actual PM measuring section with the fan, laser, detection chamber, and photodiode detector is on the left. On the right is the electronics section with its filter/ amplifier, multi-channel acquisition and internal MCU for digital signal processing and the I2C data communication interface. Since the HM3301 sensor operates from a 3.3-5V DC supply and has a standard I2C interface, connecting the module to an Arduino module or similar is relatively straightforward. A sample connection scheme is shown in Fig.3. Note that although the HM3301 sensor itself has no internal pull-up resistors on the SDA or SCL lines, the Grove-Laser module provides pull-up resistors plus logic-level converters on its PCB. That’s why the connections shown in Fig.3 are so straightforward. Of course, wiring the module up is only part of the story. You also need software that can communicate with it and display the results. So if you want to use it with an Arduino, you’ll need both a matching library and a sketch designed to communicate with the HM3301 sensor using it. When I went to the ‘Reference’ section of the Arduino website and scrolled down through the Libraries/ Sensors list, I found a library that had clearly been produced to do the job: ‘grove-laser-pm2.5-sensor-hm3301’. And when I clicked on ‘Read the documentation’ on its page, it took me to GitHub, where I found both the documentation and a link to download the library (v1.0.2). After downloading and installing the library, I found that it came with an example program called basic_ demo.ino. After verifying and uploading that program ‘sketch’ to an Arduino Uno connected to the Grove-Laser module as per Fig.3, the Arduino IDE’s Serial Monitor (set to a baud rate of 115,200) sprang into life. I immediately saw the text shown in Fig.4, with two sets of PM1.0, PM2.5 and PM10 measurements appearing every five seconds. The example output shown in Fig.4 is higher than normal (it should Fig.3: connecting the Grove HM3301 module to an Arduino is simple. All it needs is a ground connection, a 5V DC supply and the SDA and SCL pins connected to an I2C bus. Fig.4: HM3301 sample output 08:46:39.046 -> sensor num: 0 08:46:39.046->PM1.0concentration(CF=1,Standardparticulatematter,unit:ug/m3): 404 08:46:39.046->PM2.5concentration(CF=1,Standardparticulatematter,unit:ug/m3): 850 08:46:39.046->PM10concentration(CF=1,Standardparticulatematter,unit:ug/m3): 1356 08:46:39.046->PM1.0concentration(Atmosphericenvironment,unit:ug/m3):266 08:46:39.046->PM2.5concentration(Atmosphericenvironment,unit:ug/m3):524 08:46:39.046->PM10concentration(Atmosphericenvironment,unit:ug/m3):776 Practical Electronics | November | 2023 31 ► Fig.5: the Panasonic SN-GCJA5-PM sensor does not use a fan. It instead relies on passive diffusion of air through its sensing channel. Otherwise, its structure is similar to the HM3301 shown in Fig.2. The Panasonic SN-GCJA5 particulate matter sensor is in a small ► moulded plastic case measuring 37 x 37 x 12mm. In addition to the laser and photodetector, it contains all of the electronics and provides both I2C and UART digital outputs. be just above zero). That’s because I struck a match and blew it out just before that, blowing the smoke towards the HM3301 sensor. The readings jumped up quite quickly but went back to normal after about 10 seconds. So while it’s not particularly low in cost, the Grove-Laser PM module is easy to use and seems quite sensitive. Panasonic SN-GCJA5 sensor The Panasonic SN-GCJA5 sensor is again mounted inside a compact moulded plastic box that measures 37 × 37 × 12mm and weighs 13g. As with the HM3301 sensor, it includes electronics to control the laser and amplify and filter the signals from the photodiodes, plus an MCU for data processing. The output is via either an I2C or a UART TX terminal. The effective measuring range of this module is 0-2000μg/m3. The Panasonic SN-GCJA5 sensor dips in and out of stock from major UK online vendors and is usually quoted at around £20. Fig.5 shows what is inside the SN-GCJA5 sensor. As you can see, it’s similar to the HM3301 sensor innards shown in Fig.2, apart from not having any internal fan to move the air through the detection chamber. Since it has an I2C interface, it connects to an MCU like the Arduino in much the same way as the Grove-Laser module, as shown in Fig.6. But there’s one small but significant problem: connections to the SN-GCJA5 sensor are all made via a tiny 5-pin ‘pico’ connector at one end, but a connection cable with a matching plug is not supplied with it. So if you want to use – or even try out – the sensor, you first need to obtain a matching cable. Panasonic’s data sheet for the SN-GCJA5 sensor states that its connector is made by JST (Japan Solderless Terminals) Manufacturing Company, and has the type number SM05B-GHS-TB(LF)(SN). I had a lot of trouble finding any compatible cables – most cables I found with similar connectors turned out to have pins either 1.0mm or 1.5mm apart, not the 1.25mm of the JST SM05B-GHSTB(LF)(SN). Just as I was on the brink of concluding that I would not be able to try out the SN-GCJA5 sensor, a colleague emailed me to say that he believed he had found a supplier of compatible cables on AliExpress (www.aliexpress.com/item/33005797784.html). I quickly checked them out and then ordered a pack of 10 (the smallest quantity). These cost a grand total of £7.50 including postage, packing and VAT, and they took quite a few weeks to arrive. But they did finally arrive, and I used one (or half of one, to be precise) Fig.6: connecting the Panasonic SN-GCJA5 module to an Arduino is again simple. All you need to do is connect a 5V DC supply, a ground connection and the I2C bus via the SCL and SDA pins. Pin 1 isn’t used for anything, nor does it have any function. Fig.7: SN-GCJA5 sample output 08:03:23.189 -> Panaosnic SN-GCJA5 Example 08:03:23.189 -> Sensor started 08:03:23.189 -> PM:1.0, 2.5, 10, Counts: 0.5, 1, 2.5, 5, 7.5, 10, 08:03:23.236 -> 2.79,3.12,3.50,5,32,4,0,0,0, 08:04:18.209 -> 57.99,135.45,448.29,39,598,801,13,71,2, 08:04:28.238 -> 1370.39,1730.99,2392,60,440,3824,3759,37, 146,4, 08:04:48.249 -> 139.76,154.51,173.83,513,1210,153,1,2,0, 08:05:58.231 -> 62.35,73.86,83.09,200,591,120,1,0,0, 32 Practical Electronics | November | 2023 The Jaycar XC3780 module is based on the Sharp GP2Y1010AU dust sensor. Being fanless, it relies on air diffusing through 7.5mm diameter holes in the top and bottom of the sensor’s case. It has a varying DC voltage output rather than digital outputs, so conversion into a dust density figure is done by software running on the controlling MCU. to hook up the sensor to an Arduino and try it out. I needed to find a suitable Arduino library to communicate with the SN-GCJA5. Luckily, I found one in the Arduino website Reference section at: https://bit.ly/pe-nov23-GCJA5 When I downloaded this library and installed it, I found that it again included some example sketches. The first of these was called Example1_ BasicReadings.ino. When I verified and uploaded this sketch to the Arduino Uno connected to the SN-GCJA5 sensor, as shown in Fig.6, it finally sprang into life. Once again, I had to set the Arduino IDE Serial Monitor to 115,200 baud. You can see the output of the sketch in Fig.7. It gives three PM readings (1.0, 2.5 and 10) at the start of each sample line, followed by six Count figures (labelled 0.5, 1, 2.5, 5, 7.5 and 10). The first three figures are the ‘mass densities’ for the three main particle categories, while the later figures are ‘particle counts’ for all six particle size categories. Looking at Fig.7, the first values outputted are pretty low, they then shoot up to much higher levels after I lit a match about 150mm from the sensor and then blew it out, blowing the smoke towards the sensor. So the Panasonic SN-GCJA5 sensor does work, and even works quite well, once you manage to find a suitable cable to connect to it. It would be a lot easier if they supplied a matching cable! The Jaycar XC3780 sensor As mentioned earlier, Jaycar’s XC3780 dust sensor module is based on the Sharp GP2Y1010AU fanless sensor. The sensor itself is pretty compact, measuring 46 × 30 × 17.5mm, and the XC3780 module is only a little larger, at 62 × 35 × 19mm. 7.5mm diameter holes in the top and bottom of the sensor (and the PCB) allow air containing any particulate matter, dust or smoke to diffuse through the sensor. At the time of writing, the XC3780 module is available from Jaycar stores for £12.50. Fig.8: the main difference between this GP2Y1010AU ‘dust’ sensor and the Panasonic sensor shown in Fig.5 is that this one lacks any digital control electronics; it only includes analogue signal processing. Therefore, the driving microcontroller module must power the LED via pins 1-3, measure the voltage at output pin 5 and convert that into a particle level. Practical Electronics | November | 2023 Because the sensor’s mini six-pin SIL connector is on the top of the case, the XC3780 module comes with a short six-wire cable connecting it to a matching mini SIL connector on the end of the module’s PCB. There are some passive components at the same end of the board plus a four-pin SIL header with standard 0.1in/2.54mm spacing, to simplify connection to an external MCU. Fig.8 shows the components inside the GP2Y1010AU sensor itself, and as you can see, it’s similar to Fig.5 apart from not having a microcontroller to digitise and process the output signal. In this case, the analogue output signal ‘VO’ is simply made available at pin 5. Note that the centre amplifier section has a small adjustable resistor or trimpot to adjust the sensor’s effective sensitivity. But the Sharp data sheet for the GP2Y1010AU sensor warns that this trimpot is set to make the sensor conform to its specification before shipment. As a result, they advise against further adjustment of the trimpot. This specification is summarised in Fig.9, which shows how the output voltage (VO) varies with dust density. VO is close to 0.9V with zero dust in the air, rising relatively linearly to about 3.25V at a dust density of 0.4mg/m3 before flattening off at about 3.55V for a dust density of 0.53mg/ m3. It then rises very slowly to about 3.6V for a dust density of 0.8mg/m3. Note that 1mg = 1000μg. The complete circuit of the XC3780 module is shown in Fig.10, and there are only a few passive components on the PCB apart from the GP2Y1010AU sensor itself. The 150W resistor and 220μF capacitor provide decoupling and smoothing for the supply to the sensor’s internal LED, while the 1kW 33 Fig.9: this curve shows the transfer function between the output voltage of the GP2Y1010AU sensor and the corresponding dust density in mg/m3. A table (or similar) representing the points in this plot needs to be loaded into the microcontroller to perform this conversion. Fig.10: there aren’t many components on the Jaycar XC3780 module besides the Sharp sensor. All they do is filter the power supply to the module, provide a power-on indication via LED1 and route the necessary signals to a standard four-pin header for connection to an MCU. Fig.11: connecting the Jaycar XC3780 module to an MCU is straightforward. Various pin connections could be used, but this is the routing needed for the test sketch to work. It uses one digital pin (to control its internal LED) and one analogue pin (for sensing the output voltage). 34 resistor and LED1 indicate when the module is powered up. Connecting the XC3780 module to an Arduino is quite straightforward, as shown in Fig.11. The GND and VCC pins of the module can be connected to the GND and +5V pins of the Arduino. The LED pin should be connected to the IO3 (D3) pin of the Arduino while the VO/OUT pin goes to the Arduino’s ADC0 (A0) input. These are the connections needed to ensure that the XC3780 module works correctly when a specific sketch runs on the Arduino. That sketch uses a particular library to control the LED inside the GP2Y1010AU and convert its DC output voltage into the equivalent dust density. I found this library on the Arduino website in the reference → libraries → sensors section. Called PMsensor, it was written by JongHyun Woo, and the latest version is 1.1.0. When I downloaded this library (PMsensor-­master.zip’) and installed it in my Arduino IDE, I found that it came with an example sketch called PMsensor_demo.ino. This sketch provides almost no information on the correct connections for the sensor’s LED and VOUT lines, or the correct baud rate to use for the Arduino link back to the PC. However, after examining the code in the sketch, I determined that the proper connections were those shown in Fig.11, and the correct baud rate was 9600 baud. I then powered it up and got the result shown in Fig.12. I decided to adapt JongHyun Woo’s sketch into one with more helpful information in a ‘header’ section. I called this new sketch SC_PMsensor_­ demo.ino and it is available to download for free from the November 2023 page of the PE website at: https://bit.ly/pe-downloads As you can see from Fig.12, this sketch simply pulses the sensor’s internal LED once per second, then reads its output voltage and converts it into an equivalent dust density reading. This is then printed in the lines reading ‘Filter : XXX.XX’. You may have noticed in Fig.12 that at the top of the listing, the readings are low. But then they started rising because I struck a match and blew it out with the smoke passing over the top of the sensor. Precisely what these figures mean is not too clear, though. They could represent the dust density in μg/m3 (micrograms per cubic metre), or they might not. So the XC3780 dust sensor can be connected fairly easily to an MCU like an Arduino, and it does work using Practical Electronics | November | 2023 Fig.12: XC3780 sample output 15:15:25.825 -> Read PM2.5 15:15:25.825 -> Filter: 11.15 15:15:26.762 -> ========================= 15:15:26.809 -> Read PM2.5 15:15:26.809 -> Filter: 30.79 15:15:27.793 -> ========================= 15:15:27.840 -> Read PM2.5 15:15:27.840 -> Filter: 78.10 15:15:28.824 -> ========================= 15:15:28.824 -> Read PM2.5 15:15:28.871 -> Filter: 120.76 15:15:29.808 -> ========================= 15:15:32.854 -> Read PM2.5 15:15:32.901 -> Filter: 253.01 15:15:33.839 -> ========================= 15:15:40.962 -> Read PM2.5 15:15:40.962 -> Filter: 396.47 15:15:41.946 -> ========================= We assume the readings are in μg/m3 but the Useful links Suppliers n www.pakronics.com.au n https://au.element14.com/3523840 n www.jaycar.com.au Software libraries n www.arduino.cc/reference/en/libraries/ grove-laser-pm2.5-sensor-hm3301 n https://github.com/Seeed-Studio/ Seeed_PM2_5_sensor_HM3301 n www.arduino.cc/reference/en/libraries/pmsensor/ n https://github.com/ekkai/PMsensor n https://github.com/sparkfun/ SparkFun_Particle_Sensor_SN-GCJA5_Arduino_Library Panasonic SN-GCJA5 data sheet n https://bit.ly/pe-nov23-PM Sharp dust sensor application note n https://bit.ly/pe-nov23-sharp documentation is a bit vague JongHyun Woo’s library and demo sketch. But the accuracy and significance of its readings are a tad indeterminate. The bottom line Overall, I prefer the Grove-Laser module based on the HM3301 fan sensor. It is the most expensive of the three, but not unreasonably so, considering its ease of use and the apparent accuracy of its readings. I would have to rate the Panasonic SN-GCJA5 sensor as the next best; although it seems to give fairly accurate readings, it lacks a fan and also has the disadvantage of not coming with a matching cable. Reproduced by arrangement with SILICON CHIP magazine 2023. www.siliconchip.com.au Order direct from Electron Publishing GET T LATES HE T COP Y OF TEACH OUR -IN SE RIES AVAILA BL NOW! E The Jaycar XC3780 module is only about half the cost of the other two modules/sensors and is the easiest to get. However, the fact that it needs software running in the Arduino to convert its DC output voltage into dust density makes me a little less confident in the accuracy of its readings. Still, it would probably be fine if all you needed were relative readings – eg, to use it as a kind of smoke alarm. PRICE £8.99 (includes P&P to UK if ordered direct from us) EE FR -ROM CD ELECTRONICS TEACH-IN 9 £8.99 FROM THE PUBLISHERS OF GET TESTING! Electronic test equipment and measuring techniques, plus eight projects to build FREE CD-ROM TWO TEACH -INs FOR THE PRICE OF ONE • Multimeters and a multimeter checker • Oscilloscopes plus a scope calibrator • AC Millivoltmeters with a range extender • Digital measurements plus a logic probe • Frequency measurements and a signal generator • Component measurements plus a semiconductor junction tester PIC n’ Mix Including Practical Digital Signal Processing PLUS... YOUR GUIDE TO THE BBC MICROBIT Teach-In 9 – Get Testing! Teach-In 9 A LOW-COST ARM-BASED SINGLE-BOARD COMPUTER Get Testing Three Microchip PICkit 4 Debugger Guides Files for: PIC n’ Mix PLUS Teach-In 2 -Using PIC Microcontrollers. In PDF format This series of articles provides a broad-based introduction to choosing and using a wide range of test gear, how to get the best out of each item and the pitfalls to avoid. It provides hints and tips on using, and – just as importantly – interpreting the results that you get. The series deals with familiar test gear as well as equipment designed for more specialised applications. The articles have been designed to have the broadest possible appeal and are applicable to all branches of electronics. The series crosses the boundaries of analogue and digital electronics with applications that span the full range of electronics – from a single-stage transistor amplifier to the most sophisticated microcontroller system. There really is something for everyone! Each part includes a simple but useful practical test gear project that will build into a handy gadget that will either extend the features, ranges and usability of an existing item of test equipment or that will serve as a stand-alone instrument. We’ve kept the cost of these projects as low as possible, and most of them can be built for less than £10 (including components, enclosure and circuit board). © 2018 Wimborne Publishing Ltd. www.epemag.com Teach In 9 Cover.indd 1 01/08/2018 19:56 PLUS! You will receive the software for the PIC n’ Mix series of articles and the full Teach-In 2 book – Using PIC Microcontrollers – A practical introduction – in PDF format. Also included are Microchip’s MPLAB ICD 4 In-Circuit Debugger User’s Guide; MPLAB PICkit 4 In-Circuit Debugger Quick Start Guide; and MPLAB PICkit4 Debugger User’s Guide. ORDER YOUR COPY TODAY: www.electronpublishing.com Practical Electronics | November | 2023 35