Would you add another radio to your smartphone? No, not another WiFi or cellular radio; a smartphone already has that. I’m talking about something that provides connectivity through ISM bands, either 433 or 915 MHz. This can be used where you don’t have cell phone coverage, and it has a longer range than WiFi. This […]
AM broadcasting had a big problem, but usually only at night. During the day the AM signals had limited range, but at night they could travel across the country. With simple wire antennas, any two stations on the same frequency would interfere with each other. Because of this, the FCC required most radio stations to […]
A story that has been on the burner for a few weeks concerns a proposal that will be advanced to the ITU World Radiocommunication Conference 2023. It originates with French spectrum regulators and is reported to be at the behest of the Paris-based multinational defence contractor Thales. The sting in its tail is the proposed […]
When you think of an old radio it’s possible you imagine a wooden-cased tube radio receiver as clustered around by a 1940s family anxious for news from the front, or maybe even a hefty 19-inch rack casing for a “boat anchor” ham radio transmitter. But neither of those are really old radios, for that we […]
Software-defined radios or SDRs have provided a step-change in the way we use radio. From your FM broadcast receiver which very likely now has single-application SDR technology embedded in a chip through to the all-singing-all-dancing general purpose SDR you’d find on an experimenter’s bench, control over signal processing has moved from the analogue domain into […]
Over the winter, [Michael LeBlanc] thought a good way to spend his time during those long dark nights would be to scratch build his own direct conversion receiver. He was able to find plans for such a project easily enough online, but where’s the fun in following instructions? The final result incorporates what he found […]
Amateur radio is a pursuit with many facets, some of which hold more attention than others for the hacker. Though there have been radio amateurs for a century it still has boundaries that are being tested, and sometimes they come in surprising places. A recent first involved something you might consider a done deal, a […]
Of all the images that amateur radio conjures up, the great outdoors doesn’t usually figure heavily. People seem to think hams sit in a dark room at a desk heavy with radio gear, banging out Morse code into late into the night and heedless of the world outside the window. All of which sort of […]
The must-have accessory on a modern all-singing, all-dancing amateur radio transceiver is a panadaptor. Inevitably driven by SDR technology, it’s a view of a band in the frequency domain, and it will usually be displayed as a “waterfall” giving a time dimension to see transmissions over a period. [Bill Meara, N2CQR] reminds us that panadaptors […]
In the RF world, attenuators are a useful test and measurement tool. Variable units that can apply different levels of attenuation in discrete steps are even better. [DuWayne] made a 63 dB step attenuator by putting two smaller units in series, with an Arduino Nano in control of them. With a 3D printed enclosure and […]