Planet Arduino

A radio receiver is always a fun project. [Jayakody2000lk] decided that his new superheterodyne design would use an Arduino and it looks like it came out very nicely. The system has four boards. An off-the-shelf Arduino, a Si5351 clock generator board (also off-the-shelf), and two custom boards that contain the IF amplifier and mixer.

The receiver started out in 2015 without the Arduino, and there’s a link in the post to that original design. Using the Si5351 and the Arduino replaces the original local oscillator and their have been other improvements, as well. You can see a video about the receiver below.

Tuning is by a rotary encoder and the current software lets you tune from about 4.75 MHz to a little over 15.8 MHz. Of course, you could change to any frequency the Si5351 can handle as long as the mixer and other components can handle it. The IF frequency is the usual 455 kHz.

If you decide to build this yourself, the design files are on GitHub. Overall a very nice and neat design. We are always amazed how little radio architecture has changed since Edwin Armstrong’s day. Of course, we have better components, even if they aren’t meant for radio purposes.

[Dmitry] really went the distance with this project. It started as a broken DVD player scrapped for parts, and turned into this clock with way too many features. That link is a pretty a dry technical collection of the work. You’ll definitely want to have a look at it, but we’d suggest first watching the demo video after the break which is initially much more exciting.

The donor DVD hardware included a Vacuum Fluorescent display which is the nugget which [Dmitry] was after. But that board came along with some other nice things, like an integrated IR receiver. He also chose to use the PSU from the device. An Arduino is used to drive the clock. We’re not sure where he found it, but the video shows the service manual for the DVD player which must have a been a real help in interfacing with the display. The white dome on the right is a PIR motion sensor. It brings the device out of sleep mode when someone is in the room.

The case is laser-cut and started as cardboard to ensure everything fit as designed. The enclosure makes it a showpiece, but the features of displaying day, date, time, and temperature make it functional as well. Since the VFD is alpha-numeric we think this could even see future upgrades to be used as a new-mail/tweet/IM alert as well.