#339: Basics of a Super-heterodyne Receiver - how it works, and a peek at the signals @w2aew

Uploaded October 2021 | Updated September 2026, 2 weeks ago

This video presents the basics of the superheterodyne receiver, and the function of each of the blocks. The operation of the frequency conversion in the mixer and the job of the IF filtering stage are described and demonstrated on an actual radio. I use an old Realistic DX-160 shortwave receiver as an example, and show the spectral content of the RF input, the local oscillator (LO) to the mixer, the spectrally inverted output of the mixer, and how tuning the VFO / main tuning knob of the radio adjusts the LO frequency and determines which input signal lands in the IF bandpass filter to be demodulated.

As mentioned, here is a link to the basics of mixers and frequency conversion:
youtube.com/watch?v=Mm7WfVzr1ao

Video Notes:
qsl.net/w2aew/youtube/Superhet_Receiver.pdf

#339: Basics of a Super-heterodyne Receiver - how it works, and a peek at the signals

#351: Quick Tip: Cheap source of test sockets wire and for your projects and component test needs

#374: Back to Basics: JFET Current Source / Limiter circuits

#268: How to operate a ZM-2 Z-Match Antenna Tuner kit by Emtech

#281: Bipolar Transistor Switching Time Measurement

#398: My build of the SolderSmoke Challenge Direct Conversion Receiver for 40m

#222: Installing a Peak Reading kit into a Bird 43 Wattmeter

#82: How to use a Diode as a Switch / Diodes as Switches / Basics of Diode Switches

#232: More Circuit Fun: Simple transistor curve tracer using Stairstep generator circuit

#336: NJARC Presentation on the Simpson 260, including basic VOM and DMM information

#282: Part 1: How to measure complex impedance with MFJ-259B | determine sign of X

#399: Review: 3D-printed Straight-key with a great story - by the HamRadioDuo