Introduction

Planning and Preparation

1. Define Your Goals: Clearly define the purpose of your data collection and answer questions such as:
   
1. What level of accuracy do you need? 
   
2. Which features do you need to collect? 
   
3. Which attributes do you need to record?
   
4. Will you be outside of cellular coverage? 
   
5. Will you be in a high multi-path location? 
   

Keep in mind that vertical accuracy is up to twice the value of the reported horizontal accuracy.  Connecting to a real-time network using RTK will drastically improve your accuracy.

1. Update All Software and Firmware: Having the most up to date software is key for a successful survey.  This includes the:
   
1. Bad Elf Flex app software
   
2. Bad Elf receiver firmware
   
3. Phone firmware
   
4. Data collection app software 
   
2. Test in a Controlled Environment: Before collecting data at your survey location, test both your Bad Elf receiver and the data collection app you intend to use.  Ideally, this is done at a point with known coordinates, such as a survey monument.
   

The Flex Mini is only compatible with networks sending multi-signal messages (MSM), only found with RTCM 3.2 or greater.  

The Flex Mini is compatible with all RTCM formats (not CMR).

1. Offline Preparation: Keep in mind that RTK will not be available in areas without cellular service.  In such areas, the Bad Elf Flex Mini will be accurate to 3-6 feet.
   
Consider downloading offline maps for the area you'll be working in.

1. Configure Settings on Bad Elf Flex App:  Check the Bad Elf Flex app to verify your RTN login credentials are valid.
   
   
2. Avoid 2.4 GHz Mobile Hotspots When Possible: Wi-Fi creates Bluetooth interference due to being the same frequency.  Consider changing your hotspot settings to 5GHz.
   

1. Connect a Phone via Bluetooth: Make sure the Bad Elf Flex Mini is paired and connected to your phone or tablet.  Any paired phones will connect automatically. 
   

Multiple connections can hamper stability.  

1. Wait for a SBAS Fix: If the device hasn’t been used recently, this could take up to 10 minutes.
   
   
2. Select Bad Elf as Location Provider: If the app or mock locator you’re using allows you to choose the location source, select your Bad Elf receiver.
   
   
3. Open the Bad Elf App and Stream RTK Corrections (optional): Launch the Bad Elf Flex app on your connected device and follow the on-screen checklist under “Correction Mode” to stream real-time corrections.
   

A Bad Elf Flex Mini Extreme, internet, and a RTN login is required. Please see Choosing the right RTK Network for more information.

1. Configure Coordinate Transformations (optional): Especially when using a RTN, transforming your coordinates from one datum/projection to another may be necessary.
   

For ArcGIS Field Maps settings including datum transformation via profile see Configuring ArcGIS Field Maps.

Data Collection Techniques

1. Clear Sky View: For optimal signal reception, aim for an unobstructed view of the sky. Keeping the receiver away from your body and the ground by using a survey pole or other mounting solution will minimize multipath and tilt errors.
   

If you are working in a high multipath environment; such as under power lines, in dense tree canopy, or in an urban canyon; consider upgrading to the Bad Elf Flex (BE-GPS-5500). Its helical antenna and survey-grade GNSS engine provide the best chance of mitigating multipath interference.

1. Stable Position: Hold your receiver steady and vertical during data collection. Avoid tilt or movement, as this affects accuracy.
   
   
2. Verify Accuracy and Fix Type: Ensure the displayed accuracy is stable and meets your project requirements before recording a point.
   
   
3. Metadata Recording: Where possible, record metadata alongside your GNSS data. This can include details like accuracy, time stamps, fix type, etc. Metadata helps with data interpretation and analysis later.
   
   
4. Point Averaging: We recommend using a point averaging duration of at least five seconds to maximize accuracy when possible. 
   

After Data Collection

1. Export Data: Depending on your data collection method, you may need to download data logs from your receiver or export them for post-processing.  If the app allows it, ensure the proper datum, projection, vertical system, and export format is defined.
   
   
2. QA/QC: Reference your metadata before leaving your survey site to ensure all required features are saved and the accuracy meets your requirements.
   
   
3. Convert Formats:  Depending on your intended goal of the project, it may be necessary to convert file formats or schema.
   

1. Transform/Project Coordinates (Optional): If your data collection app did not perform the required transformation in real-time, use a tool like ArcGIS Pro, Blue Marble Geographic Calculator, HTDP, NCAT, or others to convert them.
   

The Bad Elf Flex App has standalone data collection abilities, see this article for more information. 

Additional Tips

1. Point One Navigation Trial: Every Bad Elf receiver comes with a free trial of Point One Navigation, an international RTN.  You can use this to test how RTK will work for you, and can also use this app to see if there are public networks in your area.
   
   
2. Review the Knowledge Base: Explore the Bad Elf Knowledge Base (https://badelfllc.zohodesk.com/portal/en/kb) or our Youtube channel for additional resources, troubleshooting guides, and best practices specific to your Bad Elf receiver model.
   
   
3. Troubleshooting: If you run into any issues:
   
1. Restart Bad Elf and phone.
   
2. Test receiver in area with great sky-view completely free from overhead obstructions, while elevated off the ground.
   
3. Clear all Bluetooth pairings on phone and Bad Elf and re-pair
   
4. Verify only one Bad Elf is connected to only one phone
   
5. Update all software and firmware
   
6. Turn off mobile hotspot, or change to 5GHz
   
4. RTK:
1. Verify GPS fix
2. Check internet connection
3. Verify login credentials
4. Try multiple mount points
5. Verify coordinate transformations
6. Eliminate multipath error from overhead obstructions
   

Record a track log to analyze and identify problems. See this article for more information.

1. Contact Support: If you have any questions or encounter issues during data collection, feel free to contact Bad Elf Support at support@bad-elf.com with screenshots for assistance. We're happy to help!