Download EECS189 Senior Design Project General Coverage

EECS189 Senior Design Project
General Coverage Superheterodyne Transistor Radio Receiver
A number of radio receiver structures exist, such as direct tuning, regenerative, reflex, etc.
However, since its invention during World War I, almost all of the radios built use the
superheterodyne principle. In this project, you will build a superheterodyne transistor radio that
will cover the frequency bands 560 kHz-30 MHz (in 5-6 ranges) with an audio output power of
2 Watts (maximum).
A superheterodyne radio consists of a tuner, possibly an RF (Radio Frequency) amplifier, a local
oscillator, a mixer, an IF (Intermediate Frequency) amplifier, a detector, and an AF (Audio
Frequency) amplifier. At this point you are familiar with the design of the tuner and the audio
amplifier. You will need to figure out how other blocks operate and how all of the circuit can be
put together. You can use a standard design but you are expected to understand the operation of
all of the various blocks. You will need to design the tuner stage and the AF amplifier. You are
expected to build your own printed circuit board and place the radio in a presentable enclosure
with a functional interface. The cost will be a consideration and the cost of your product should
compare favorably with a standard radio such as the GE Superadio III (which only covers the
AM band 560-1600 kHz). There should be some reception on shortwave bands with a whip
antenna and an external antenna should improve the reception. The overall design will likely use
about 8-10 transistors and about 3 IF transformers. A good methodology involves reverse
engineering an existing radio, understanding it well, and then completing the design according to
the specifications. Various resources are available on the Web for similar projects. The book
“The ARRL Handbook for Radio Communications” can be highly useful for various stages of
the design. The instructor will provide guidance through the two quarters. The Web sites below
can offer additional information and resources.
homepage.ntlworld.com/henry01/mediumwave_radio/mediumwave_radio.htm
www.hanssummers.com/radio/transistor
homepage.eircom.net/%7Eei9gq/rx_circ.html
homepage.eircom.net/%7Eei9gq/pcb.html
www.oselectronics.com
www.oselectronics.com/ose_p23.htm
www.gibsonteched.com/G-536NB.html
If you would like to pursue this project, make an appointment ([email protected]) to discuss.