> For the complete documentation index, see [llms.txt](https://docs.aethlabs.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.aethlabs.com/microaethalometer-tm-ma600/quick-start-guide/important-information-before-getting-started.md).

# Important Information Before Getting Started

**1) The microAeth® Manager application** for MacOS and Windows can be used to modify all instrument settings; only some settings can be modified using the on-board user interface on the front panel of the MA600. The MA600 also outputs real-time RS-232 serial data through the DB9 connector on the rear panel for integration with data acquisition systems.

**2) Timebase:** The MA600 can acquire data on timebase settings of 1, 5, 10, 30, 60, or 300 seconds. The 1, 5 and 10 second timebases should only be used under special circumstances where a decreased signal-to-noise ratio is acceptable; at these settings instrumental noise is larger and typically requires the highest flow rate and/or post-processing. For continuous stationary monitoring we recommend starting at the **60 second** timebase; longer timebases such as 300 seconds further reduce noise for long-term deployments.

**3) Flow Rate:** The MA600 pump can operate at flow rate settings of 100, 125, 150, 170, 200, 225, or 250 ml/min. A higher flow rate can contribute to greater measurement sensitivity but will use more filter tape and more power. **150 ml/min** is the recommended starting flow rate for the MA600.

**4) The lowest wavelength light source enabled will typically trigger the attenuation (ATN) tape advance threshold.** For example, if 5 wavelengths are enabled, the UV channel should always trigger the tape advance.

**5) Measurement Wavelengths:** What are you trying to measure? What wavelengths are important for your measurements? **More is not always better. Operating with the IR channel only will increase tape life by at least 2.3x** — worth considering for continuous sites where tape changes are less frequent.

**6) Tape advance ATN threshold:** If DualSpot® is enabled, a higher ATN threshold can be used, as DualSpot will help correct for aerosol composition dependent loading effects.

**7) DualSpot® vs SingleSpot™:** A flow rate of 100 ml/min or greater is highly recommended when using DualSpot® loading compensation (the MA600's recommended 150 ml/min satisfies this). Using **DualSpot®** will allow measurements at higher ATN loadings (longer sampling at each filter tape location) as the data are compensated in the BCc data column.

{% hint style="info" %}
Due to the flow split between Spot 1 and Spot 2, the measurement sensitivity in DualSpot® mode will be lower than in SingleSpot™ mode for the same total flow rate. When the DualSpot calculation and compensation is active (when ATN for BC1 ≥ 3) the data will have more noise; this is expected behavior. Simple smoothing can be applied to reduce the noise, or the smoothed columns in the data file can be used if helpful.
{% endhint %}

**8) Protect the inlet and outlet ports from water and other contaminants.** There must be limited restriction to flow while protecting against water, insects, and other objects that can block or infiltrate the instrument air pathway through both the inlet and outlet ports.

{% hint style="warning" %}
Be sure that the aerosol inlet is at atmospheric pressure and that there is no differential pressure between the aerosol inlet and the operating environment. If sampling from a plenum or chamber, it must be at the same pressure as the instrument. If other instrumentation is measuring in parallel, always use a dedicated sampling line for the MA600.
{% endhint %}

For high-humidity environments, an optional built-in **Nafion dryer** is available to manage moisture in the sample stream.

**9) Power:** The MA600 is powered by **external 12V DC** and is intended for continuous operation. Connect the 12V power adapter to the sealed M8 connector labeled 12V DC IN. If the optional built-in Nafion dryer is installed, an **external pump** is required to provide the purge counterflow for the built-in Nafion dryer. A **second** 12V supply must be connected to the external purge pump if supplied with the instrument.

**10) Verify and calibrate flow.** Verify flow rates using the on-board **Test Flow** menu and an external AethLabs Flow Calibration Kit before deploying. The instruments are initially calibrated near sea level; only calibrate the flow system if there is an error in the measured flow. Calibrate at the deployment location, especially at **higher elevations**, to compensate for the change in altitude.

**11)** To get the best data from the MA600, we highly recommend that the instrument warm up for approximately **30 minutes** so that it can equilibrate.

**12)** If you change sampling settings or download data (non-streaming data), you must **stop the instrument measurement** before being allowed to make a change. Every time the measurement starts into the sampling mode, the filter tape cartridge automatically advances to a clean spot. Stopping and starting the instrument unnecessarily will therefore consume more tape than sampling continuously.