Virtual Lab Project JourneyFollow article
This blog is to explain our journey through completing the virtual lab project, the main objective of this project is to allow users to be able to make measurements on the circuits connected to the Red Pitaya. In order to achieve this, the Red Pitaya would be connected to the internet, whereby users can access the Red Pitaya anywhere, as long as they are connected to the internet.
For starters, the first step that was done was to set up the Red Pitaya, and in order to achieve this, following the quick start instructions found on their website here, the Red Pitaya was up and running in no time. First of all, the SD card had to be configured, obtaining the image file provided and unzipping it, we then wrote the files into the SD card, following the instructions specifically for the operating system windows.
Since the steps given to set up the Red Pitaya are straight forward, after slotting in the configured SD card, connecting the Red Pitaya to the router with an Ethernet cable and connecting it to the power supply. Entering the MAC address of our Red Pitaya into the website mentioned previously, we were able to access the online interface immediately. Then port forwarding the IP address of the Red Pitaya, with the link given anyone can access our Red Pitaya right here.
- If link does not work, please check that ' :90 ' is added on the end, or copy the link here: http://internshipprojects.ddns.net:90
As for the circuits to be connected to the Red Pitaya, coming up with a band-pass filter circuit and a band-stop filter circuit, as shown in the pictures above. There it illustrates the design we had in mind and the cut off frequencies set with the resistor values we were able to get. In the picture, it also shows the frequency response which shows the frequency ranges which will be able to pass through the filters, and as well as the gain.
Band-pass filter PCB design
Band-stop filter PCB design
With that designed, the next step was to design the printed circuit boards (PCB). Using DesignSpark PCB, first the schematic designs for the circuits were created, they were then translated into PCB as shown in the pictures above. Generating the Gerber files, the circuits were then sent to get fabricated, in preparation to finalise the circuits to be connected to the Red Pitaya. While that was getting fabricated, we went ahead to prototype the circuits on breadboards to ensure everything was working, before the whole circuit was soldered.
To read more about our design process for the PCB, please click here.
Due to the constraint of time, we came across a few problems while preparing the final PCB for the project, finding that the PCB we were provided were not up to standards in result failing to let the circuit work. So in the end we decided to compromise, and use a stripboard instead, but since we faced a few problems with that as well, we decided to stick with using a breadboard, as shown in the picture above.
With the circuits prepared, all that was left to do was connect the circuits to the Red Pitaya. Using oscilloscope probes and SMA-BND adapters, we used one of the probes to act as the output (OUT1) from the Red Pitaya, and in this case as the input for the circuit. Then the other probe (IN1) was connected to the output of the circuit, whereby the user can monitor the output of the filter, then since the user can control the input into the circuit, they can explore on the functionality of the filters. While the +15V and -15V required by the circuit is provided separately to the circuit by a separate power supply.
Originally we had planned for the two filters to be connected to the Red Pitaya, but since we only had 2 oscilloscope probes with SMA-BNC adapters, we chose to use instead to just use one filter in the end; connecting the input and output to the band-pass filter instead. The final set up can be seen in the picture right above.
To explore with the final virtual lab project, please click here, and read the other blog made separately for it.