February 16, 2014

 

To: Dr. David Michelson

 

From: Jacklyn Dang, L2C4 Team Leader

 

This memorandum serves as an update for progress of the EECE 380 Design Studio III team, L2C4, during the week of February 10 – February 16, 2014.

 

We had our weekly team meeting on Tuesday, February 11, where we talked about our progress in the software and hardware portions of the project from the previous week. At the conclusion of the meeting, we decided on the goals to be attained by the end of the week.

 

Updates on Hardware Portion:

 Last week, we had placed an order for some high frequency op-amps to provide gain in the peak detector, and output signal of the mixer. We hoped that using an LM7171 200MHz op-amp would allow us to reach the needed gain at 10MHz, however we were unable to successfully build a non-inverting amplifier. It appeared that even a simple buffer would not work with this IC, outputting a DC voltage that correlated with the supply voltage of the op-amp. This failure led us to designing common-emitter BJT amplifiers instead. These designs have carried out into the subsequent week, as we are still working on obtaining a high gain with poles at the appropriate frequencies.

 

Updates on Software Portion:

As mentioned in the previous memo, we had completed the software portion of the project, but had not been able to test it without the completion of the hardware portion. During the first lab section this week, we worked on adding both required and extra features to the software portion of the project. We focused on implementing a user friendly and interactive interface for the analyzer that had the ability to zoom in and out on specific areas. We also aimed to add a marking feature to our spectrum analyzer. We were successfully able to implement and test the zoom feature, as well as implement a marker. We have been unable to test the marker due to a problem with LabView that will be described below.

 

During the second lab session we encountered a problem with the LabView program. The program itself seemed to be lagging quite significantly and therefore it majorly affected the updating of values from the MyDAQ to the graph in LabView and we would not get a continuous, fast updating view of our signal. We know that this is not caused by our sample number or sample rate in the MyDAQ assistant as we had previously used the same values and not had any problems, but we also experimented by increasing samples and sample rate which still produced the lagging output. We have consulted with the TA and with the lab technician that was available during the lab, but neither had any insight into the problem. We believe that the computer we were on was just running slowly that day, and that the next time we run LabView  the program will run smoother. If not our task for next week will be finding a solution to this current problem.

We plan on meeting during the reading week to continue working on the hardware portion of the project. Our next scheduled meeting will be on Monday February 24th.