When a sinusoidal waveform is periodically modulated in either amplitude or frequency, sidebands are generated as a result of this carrier modulation. These sidebands can be measured using a lock-in amplifier. Zurich Instruments' lock-in amplifiers (such as the HF2LI and the UHFLI) can measure up to 8 frequencies simultaneously and...
Double-sideband suppressed-carrier (DSB-SC) modulation is an amplitude modulation that consists only of the two symmetrical sidebands and no carrier band. I came across this scheme in an ultrasound application, where power utilization can be maximized when all power is available on the sidebands. It turns out that DSB-SC modulation can...
Following my previous blog post , people advised me to try to broadcast FM radio too. For this, I had to retreat into Zurich Instruments' shielded radiation lab, so that my experiment would remain concealed. It then took about 5 minutes to broadcast tunes from my mobile phone's 3.5 mm...
Someone at Zurich Instruments soldered a 3.5-mm headphone socket to a BNC cable and attached a 75-cm antenna wire to the Signal Input of the UHFLI Lock-in Amplifier with the UHF-PID PID/PLL option and was happily listening to FM radio. Abuse alert! I instantly had to copy that one.
