In this episode Shahriar explores the principle operation of automotive FMCW radars. Thanks to a donated automotive radar module, various components of the system can be examined and explored. The PCB reveals three die-on-PCB ASICs responsible for generating and receiving 77GHz FMCW signals coupled to a 2D array of antennas. Several microwave components such as rat-race couplers and branchline couplers can also be observed. PCB rulers from SV1AFN Design Lab also show these microwave components at much lower frequencies. Two other ICs are used for ramp generation and PLL as well as a multi-input LNA/PGA/AAF with 12-bit ADC for IF processing. All components are examined under the microscope and the frequency of operation is calculated by measuring the branchline coupler’s dimensions.
Finally a simple Doppler effect radar is constructed by using a doubler, power divider, mixer and a pair of Vivaldi horn antennas. The Doppler effect can be observed by moving an object in front of the antenna pair.
In this episode Shahriar reviews the Tektronix RSA607A real-time spectrum analyzer which operates from 9kHz to 7.5GHz. The instrument has a 40MHz wide analysis window with a DANL of -160dBm. The built-in tracking generator is capable of measuring return loss, cable loss and DTF measurements without a need for an external coupler. This review is organized as follows:
01:03 – Model comparison and overview.
03:25 – Front & rear panel overview.
05:31 – Complete unit teardown & examination.
16:33 – Reverse engineering and experiments with a drone remote control transmitter.
39:27 – Characterizing and experimenting with an ISM band diplexer.
47:29 – Return loss measurements of a tunable band-pass filter.
53:23 – Concluding remarks.
In this episode Shahriar reviews the Deepace KC901V 6.8GHz handheld network analyzer. This battery-powered instrument is an RF multi-instrument integrating VNA, spectrum analyzer, field strength meter, and a low-frequency signal generator. It can also perform signal port vector measurement and 2-ports simple vector network analyzing (S11, S21). The review is organized as follows:
01:24 – Instrument overview & block diagram.
05:36 – Full teardown along with RF and digital board analysis.
14:30 – Power on, calibration and S11 measurement of an antenna.
23:46 – Calibration for S21 and measurement of a tunable filter plus phase shifter.
32:23 – Distance to fault measurement of an SMA cable chain.
36:24 – Spectrum analyzer measurements and limitations.
43:16 – Signal generator measurements and issues.
48:20 – Other features and concluding remarks.
50:07 – Giveaway!
In this short episode Shahriar takes a close look at an HP 83475B Lightwave Communication Analyzer / Oscilloscope which offers a 500MHz bandwidth on both the electrical and optical inputs. The sub-sampling scope has a minor issue where the CRT brightness knob has been disconnected internally.
The teardown of the scope reveals the sub-sampling ADCs, O/E front-end as well as CRT driver circuitry. The operation of the scope is demonstrated using various electrical and optical NRZ and multi-level signals.
The Signal Path (TSP) is an electrical engineering video blog for industry professionals, students and hobbyists. TSP is a non-for-profit website dedicated to provide free education spanning a wide range of electrical engineering topics. Equipment reviews, tutorials and repair videos are posted regularly.