Lab 1: Test and Measurement
Lab 1 was designed to familiarize us with the equipment in the RF lab. Various voltage outputs were created on the waveform generator and measured and analyzed using the oscilloscope.
Section 1.1 - The Tektronix AFG1062 function generator was set to output a 2Vpp, 10kHz signal, which was routed to the Tektronix MDO3032 oscilloscope via a BNC cable. The waveform was captured with a time scale of 40us, then again with a time scale of 20us. Cursors were used to measure the maximum and minimum voltages of the signal.
In response to the question, a time scale of around 20-50us would be a good setting for a 10kHz signal.
The aforementioned sine wave was measured on a digital multimeter and the results are shown below. The multimeter displays the RMS voltage of the signal.
Section 1.2 - In order to see a 1kHz intelligence signal on a 10kHz carrier, a time scale of approximately 500-250us would be appropriate.
The function generator was used to generate an 1kHz amplitude modulated signal with a 10kHz carrier which was then viewed on the oscilloscope.
After creating a basic AM signal, a more complex signal was generated and analyzed using the RF input of the oscilloscope. The function generator was set to generate a carrier frequency of 1230kHz with an amplitude of 100mVpp. This was then modulated with a 1kHz intelligence signal at 50% modulation and viewed on the spectrum analyzer. This was then repeated at 100% modulation and measured to gather data about the power levels of various frequencies at different modulation levels. This data is shown in the tables below. In response to the question, some other uses for a spectrum analyzer include finding specific frequencies of radio noise or checking the frequency accuracy of a signal generator.
Section 1.3 - This section involves creating a 1kHz AM signal with 50% modulation and a 50kHz, 100mVpp carrier, then observing the signal using the oscilloscope's fast Fourier transform feature. This is shown in the pictures below. Cursors were used to measure the frequency and power levels of the carrier and sidebands. These measurements are shown in the tables below. These values are not the same as using the spectrum analyzer because the carrier frequency has changed.
