Department of Electrical Engineering

Graduate Analog Lab

(aka RF Project Laboratory)

The format we will use involves discussing the ways that a particular function can be accomplished for a few class periods. These introductions are kept non-rigorous and informal (there is no need to prove anything --- we have history on our side!), with maximum ``round-table''-type participation. Following each discussion, a design problem is assigned in the form of a specification sheet. The objective is to complete a paper design and construction of a circuit that meets the specifications. The paper design should be detailed, neat, and in a form that a technician might reasonably be expected to work from. Unspecified component types or values are unacceptable. A description of the operation of the circuit, emphasizing its important features, and analysis demonstrating conformity with specifications are required.

This class is for motivated self starters. While we will be present in the laboratory, and meeting with you individually to discuss your designs, the staff is not available to help your troubleshoot your designs. ``Why doesn't my circuit work?'' is a question that we do not have an answer for. However, we can, and will, talk at length about ``How to find what is wrong with your circuit''. Likewise, successful completion of this course may require a significant amount of your time. We firmly believe that full immersion is the appropriate atmosphere for teaching these concepts.

The level of the material in the class is intended to be below the complexity and difficulty of the material and assignments introduced in Advanced Circuit Techniques (6.331), however the choice of topics covered in this class are such that this class and 6.331 may be taken in either order.

**Lab 1 ``High Speed Amplifier Lab''**

After a classroom review of operational and transimpedance amplifiers, students explore the use of these devices in the lab. Students compare the topology and performance of devices such as the LM6171 voltage op amp and the LM6181 transimpedance amp, and attempt to measure the unity gain settling time. Using the LM6181 and a high speed buffer such as the LH0002, LH0033, or LH4002, students build an externally compensated version of the LM6171 and explore various open loop transfer function shapes. Traditional op amp topologies such as the LM301 and LF411 are also used.**Lab 2 ``Phase Lock Loops Lab''**

A brief treatment of phase lock loops, using modern building blocks and student constructed blocks, is done, covering the concepts of lock range, acquisition, and performance specifications. Using the CD4066, students build a number of phase lock loops, including one to acquire the 19 kHz subcarrier from an FM stereo composite signal.**Lab 3 ``FM Stereo Decoder Lab''**

Using the results from Lab 2, students finish the design and construction of a FM stereo composite signal decoder, similar in function to the (now discontinued) National Semiconductor LM1800.**Lab 4 ``Oscillator Lab''**

After a review of describing functions and phase shift topologies, students construct a number of simple oscillator circuits and analyze them as possible VCOs, with respect to center frequency stability and tuning range. A frequency stable and amplitude stable 38 kHz oscillator is built.**Lab 5 ``Translinear Mixer Lab''**

The accuracy and dynamic range of translinear multipliers can be greatly improved with a few op amps to provide base current and biasing to some of the devices. A high accuracy multiplier, suitable for use as an audio frequency mixer, is constructed from basic parts such as the LM3086 transistor array and compared to the LM1496.**Lab 6 ``FM Stereo Encoder Lab''**

Using the results from Labs 4 and 5, students finish the design and construction of a FM stereo composite signal encoder, and test it against the decoder they built in Lab 3.**Lab 7 ``Frequency Synthesizer Lab''**

The students build a crystal based phase lock loop capable of tuning from 88 MHz to 108 MHz.**Lab 8 ``RF Communication Lab''**

An introduction to the concerns and tradeoffs in building RF circuits is presented. Using the results from Labs 6 and 7, students complete the construction of a low power FM stereo transmitter.

This page has been accessed at least times since January 29, 2002. Last updated: Tue Feb 5 07:16:53 EST 2002, by Kent Lundberg.