Equipment Overview

The Trimble Catalyst DA2 GNSS system delivers positioning-as-a-service to Android and iOS devices. With the addition of the simple, lightweight Trimble DA2 GNSS receiver and an on demand accuracy-based subscription, turn your smartphone or tablet into a precision mapping, navigation, and measurement tool you can use with any location enabled app or service.

The DA2 receiver antennae can be attached with a simple handle accessory to an Android mobile device that doesn’t require a survey pole. If you’re looking for a more convenient and comfortable way to collect data in the field this may be a preferable option.

The Cat2- DA2 receiver antennae can be attached to the top of the survey pole with the Android mobile device clipped to the pole as well. If you’re planning on collecting data in a more densely forested area, perhaps a survey pole would be preferable.

Tall Timbers maintains multiple DA2 units designated Cat1, Cat2, Cat3, and Cat4. The unit number can be found on the label located on the underside of the DA2 receiver.

The DA2 receiver requires a power source during operation. Before leaving for the field, make sure the mobile device and the DA2 power supply are fully charged. For extended fieldwork, bring an additional fully charged power supply in case the primary power source becomes depleted.

For more information on Terraflex and setting up with the DA2 antennae, please go to the 'Connecting to a DA2 or R series receive'.

Before Leaving the Office

1. Make sure the Android device and the power packs for the DA2 receiver antennae are fully charged. Always bring extra power packs with you just in case you start running low.
2. While connected to the WiFi in the office, open up the Trimble TerraFlex app on the Andoid device (pass code 32312) and make sure your map project is synced up with your device. It should start syncing right when you open the TerraFlex app.

Note: If you need to sign in to the Terraflex app using the email account that corresponds to the DA2 receiver antennae that the handheld is with (look on the underside of the receiver antennae where it should be labelled). Enter the password provided to you by the Geospatial Lab.

If it does not sync, you can select the menu (3 lines on the top left) and select Check for Project updates.

3. On the menu pane, you can select projects by selecting Change Project and open up the desired map project. You should hopefully see the one made for your project in Trimble Connect.

4. Open up your project to make sure it has the data template you created with it as well.

1. Test to make sure the DA2 receiver antennae is working okay and connected to Android device via Bluetooth as well. Press and hold the Power button on the bottom of the DA2 receiver until the LED starts blinking blue.
2. Go to Menu > GNSS Configuration and make sure the ‘Location provider’ connects to the DA2. If it says ‘None’ or ‘Internal’, click the arrow on the right side of ‘Location provider’. A green ‘CONNECTED’ logo should appear next to the Trimble. If it looks like it is trying to connect to the DA2 but failing, restart the Android.

Connecting the DA2 and Location Status

Connecting to the DA2 does not automatically mean that the receiver has achieved sufficient positional accuracy. Before collecting field data, click ‘More info’ next to Location Status in TerraFlex to confirm that the DA2 has established an acceptable GNSS position.

Trees, buildings, and other obstructions can interfere with satellite signals and can cause the receiver to take longer to achieve the required accuracy. Take the DA2 receiver outside and give it as clear a view of the sky as possible. When using a survey pole, keep the DA2 receiver at the top of the pole and maintain the pole in an upright position.

In ‘Location status’ we can view multiple values including satellite availability, horizontal accuracy, and vertical accuracy:

Satellite availability: This shows how many satellites are available to the DA2. It’s recommended to be connected to at least 7 satellites (the more the better). Satellite availability can change depending on your location and surrounding obstructions.

Horizontal accuracy: This shows the estimated uncertainty of the receiver's position across the ground. This is particularly important when collecting the location of features.

Vertical accuracy: This shows the estimated uncertainty associated with elevation. Vertical accuracy and horizontal accuracy are separate measurements and may not be the same. If elevation is important to the project, verify that the vertical accuracy also meets the project's requirements before collecting the feature.

Do not collect data until centimeter-level accuracy is attained. If it doesn’t seem to be connecting to the DA2 receiver after waiting 5 minutes or more, try rebooting the Android.

Collecting Data

1. Once you have obtained centimeter-level accuracy, return to the ‘Home’ page of your current project and (under Collect) select the data type you wish to start collecting and fill out the data form.
2. Once the form is filled out, select the Map icon (make sure the accuracy is still in cm). The orange point indicates your location, then select the check mark in the upper right corner.
3. It will return to your text form. If okay with the form, again select the check mark in the upper right corner. Once submitted, you should see the number increase in the number of forms.

4.When you are done make sure you have synced your data with Trimble Connect before you download.

5.Turn off both the Android device and the DA2 receiver.

6. To download your data, consult Part1: Trimble GPS Connect and Map Setup

page 10 (Steps 23-26).

Please see the Trimble TerraFlex Help Portal  for more information on TerraFlex for the field.

Working with the Map

If background/reference layers have been set for your map. Select the Map icon in the bottom right of your current project. Go to the three dots in the upper right-hand corner of the map and select Map layers where you can then turn on and off each layer by clicking on the eye under ‘Reference layers’.

Here, you can also set a Base map from maps provided by Trimble, or select an offline map created in Trimble Connect.

For more information, go to 'Collecting data and working with forms in TerraFlex'.