Collaborate Disseminate
If you’ve scavenged some random keypads and want to reuse them in a project without the hassle of figuring out the pinouts, then [Cliff Biffle] has an interface module for …read more Continue reading Keypad Interface Module Reverse Engineers Pinouts So You Don’t Have To
It’s been a long time since computer hobbyists stored their programs and data on cassette tapes. But because floppy drives were expensive peripherals and hard drives were still a long …read more Continue reading A Cassette Interface for a 6502 Breadboard Computer, Kansas City-Style
As side-channel attacks go, it’s one of the weirder ones we’ve heard of. But the tech news was filled with stories this week about how Janet Jackson’s “Rhythm Nation” is …read more Continue reading Hackaday Links: August 21, 2022
It’s no secret that the era of the landline telephone is slowly coming to a close. As of 2020, it was estimated that less than half the homes in America …read more Continue reading Arduino Caller ID Display is Better Late than Never
Hardware development often involves working with things that can’t be directly perceived, which is one reason good development tools are so important. In appreciation of this, [David Johnson-Davies] created the IR Remote Control Detective to simplify working with IR signals. While IR remote controls are commonplace, there are a number of different protocols and encoding methods in use across different brands. The IR Detective takes care of all of that with three main components, none of which are particularly expensive. To use the decoder, one simply points an IR remote at the unit and presses one of the buttons. The …read more
Continue reading IR Detective Eases Development with Compact Decoding
For a hobby that’s ostensibly all about reaching out to touch someone, ham radio can often be a lonely activity. Lots of hams build and experiment with radio gear much more than they’re actually on the air, improving their equipment iteratively. The build-test-tweak-repeat cycle can get a little tedious, though, especially when you’re trying to assess signal strength and range and can’t find anyone to give you a report.
To close the loop on field testing, [WhiskeyTangoHotel] threw together a simple ham radio field confirmation unit that’s pretty slick. It relies on the fact that almost every ham radio designed …read more
Continue reading Simple Decoder Serves as Solo Ham’s Test Buddy
In the first part of our series on in-band signaling, we discussed one of the most common and easily recognizable forms of audio control, familiar to anyone who has dialed a phone in the last fifty years – dual-tone multifrequency (DTMF) dialing. Our second installment will look at an in-band signaling method that far fewer people have heard, precisely because it was designed to be sub-audible — coded squelch systems for public service and other radio services.
To review, an in-band signaling system is loosely defined as any system that sends control information along with the main content …read more
One late night many decades ago, I chanced upon a technical description of the Touch-Tone system. The book I was reading had an explanation of how each key on a telephone sends a combination of two tones down the wire, and what’s more, it listed the seven audio frequencies needed for the standard 12-key dial pad. I gazed over at my Commodore 64, and inspiration hit — if I can use two of the C64’s three audio channels to generate the dual tones, I bet I can dial the phone! I sprang out of bed and started pecking out a …read more
Continue reading In-Band Signaling: Dual-Tone Multifrequency Dialing
