Category Archives: radio

VCF East: SDR on the Altair 8800

You’d be forgiven if you thought software defined radio (SDR) was a relatively recent discovery. After all, few outside of the hardcore amateur radio circles were even familiar with the concept until it was discovered that cheap USB TV tuners could be used as fairly decent receivers from a few hundred MHz all the way up into the GHz range. The advent of the RTL-SDR project in 2012 brought the cost of entry level SDR hardware from hundreds of dollars to tens of dollars effectively overnight. Today there’s more hackers cruising the airwaves via software trickery than there’s ever been …read more

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Posted in radio, radio hacks, retrocomputing, VCF, VCF East, VCF East XIII | Leave a comment

Restoring A 1930s Oscilloscope – Without Supplying Power

We’ve all done it: after happening across a vintage piece of equipment and bounding to the test bench, eager to see if it works, it gets plugged in, the power switch flipped, but… nothing. [Mr Carlson] explains why this is such a bad idea, and accompanies it with more key knowledge for a successful restoration – this time revitalising a tiny oscilloscope from the 1930s.

Resisting the temptation to immediately power on old equipment is often essential to any hope of seeing it work again. [Mr Carlson] explains why you should ensure any degraded components are fixed or replaced before …read more

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Posted in Mr Carlson, oscilloscope, radio, repair hacks, restoration, teardown | Leave a comment

Fail Of The Week: Never Assume All Crystals Are Born Equal

You should be used to our posting the hacks that didn’t quite go according to plan under our Fail Of The Week heading, things that should have worked, but due to unexpected factors, didn’t. They are the fault, if that’s not too strong a term, of the person making whatever the project is, and we feature them not in a spirit of mockery but one of commiseration and enlightenment.

This FOTW is a little different, because it reveals itself to have nothing to do with its originator. [Grogster] was using the widely-available HC-12 serial wireless modules, or clones or even …read more

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Posted in radio, radio hacks, radio module, serial wireless module | Leave a comment

An SSB Transceiver On Only One Type of Transistor

There are a multiplicity of transmission modes both new and old at the disposal of a radio amateur, but the leader of the pack is still single-sideband or SSB. An SSB transmitter emits the barest minimum of RF spectrum required to reconstitute an audio signal, only half of the mixer product between the audio and the RF carrier, and with the carrier removed. This makes SSB the most efficient of the analog voice modes, but at the expense of a complex piece of circuitry to generate it by analog means. Nevertheless, radio amateurs have produced some elegant designs for SSB …read more

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Posted in radio, radio hacks, ssb, transceiver | Leave a comment

Monitor Foot Traffic Using Radio

We talk a lot about information security around here, but in reality it’s not at the forefront of everyone’s minds. Most people are content to walk around with their phones constantly looking for WiFi or Bluetooth connections despite the dangers. But if you’re not a black hat sort of person, you can do something like [Verkehrsrot] did and use all of these phones to do something useful and harmless.

[Verkehrsrot]’s project involves building a radio listening device in order to get an estimate of the amount of traffic in a particular area. The device polls for and detects WiFi and …read more

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Posted in listening, radio, security, traffic, wifi, wireless hacks | Leave a comment

Speaking the Same Language as a Wireless Thermometer

Temperature is a delicate thing. Our bodies have acclimated to a tight comfort band, so it is no wonder that we want to measure and control it accurately. Plus, heating and cooling are expensive. Measuring a single point in a dwelling may not be enough, especially if there are multiple controlled environments like a terrarium, pet enclosure, food storage, or just the garage in case the car needs to warm up. [Tim Leland] wanted to monitor commercially available sensors in several rooms of his house to track and send alerts.

The sensors of choice in this project are weather resistant …read more

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Posted in radio, superheterodyne, temp, temperature, thermometer, wireless, wireless hacks | Leave a comment

An Autonomous Drone For Working Rare Squares

Amateur radio is an extremely broad church when it comes to the numerous different activities that it covers. Most of the stories featuring radio amateurs that we cover here have involved home-made radios, but that represents a surprisingly small subset of licence holders.

One activity that captivates many operators is grid square collecting. The map is divided into grid squares, can you make contact with all of them? Land-based squares in Europe and North America are easy, those in some more sparsely populated regions a little less so, and some squares out in the ocean are nigh-on impossible. As an …read more

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Posted in KX3, radio, radio hacks, Raspberry Pi, Waverider | Leave a comment

Repairs You Can Print: Fixing a Chewed Up Remote

What is it about remote controls? They’re like some vortex of household chaos, burrowing into couch cushions while accusations fly about who used it last. Or they land in just the right spot on the floor to be stepped on during a trip to the bathroom. And don’t get us started about the fragility of their battery case covers; it’s a rare remote in a house with kids whose batteries aren’t held in by strips of packing tape.

But [Alex Rich]’s Bose radio remote discovered another failure mode: imitating a dog chew toy. Rather than fork out $90 for a …read more

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Posted in radio, remote, repair hacks, Repairs You Can Print, Trinket, tv | Leave a comment

Drink Lots Of Beer To Raise Your Monopole

When we published a piece about an ADS-B antenna using a Coke can as a groundplane, Hackaday reader [2ftg] got in contact with us about something with a bit more… stature.

A monopole groundplane antenna is a single vertical conductor mounted on an insulator and rising up above a conductive groundplane. In radio terms the groundplane is supposed to look as something of a mirror, to provide a reflection of what would come from the other half of a dipole were there to be two conductors. You can use anything conductive as your monopole, a piece of wire, (in …read more

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Dust Off Those AM Radios, There’s Something Good On!

If you are into vintage electronics or restoring antique radio equipment you may be very disappointed with the content offerings on AM broadcast radio these days. Fortunately there is a way to get around this: build your own short-range AM broadcast station and transmit curated content to your radios (and possibly your neighbors). There are several options for creating your own short-range AM broadcast station, and this gives you something fun to tune into with your vintage radio gear.

Antique Radios See Daily Use Once More

We see a ton of antique radios turned into Internet radios. Perhaps this is …read more

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Posted in internet radio, mp3 player, playlist, radio, radio hacks, transmitter | Leave a comment