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iPhone Interface For Ham Radio Mates Old With New
jjp9999 writes "By using the same technology found in older modems, Thomas Tumino, vice president of the Hall of Science Amateur Radio Club, has invented an iPhone interface for ham radios. He told The Epoch Times, 'Today there are iPhone apps where you can use the systems in the phone — and its sound card, which is being used as a modem ... And then you connect that into your radio with an interface like this, that just isolates the telephone from the radio, and then you can do all sorts of things.'"
Maybe now they will have a signal good enough to make a call.
This is one huge step for locally based information networks finally becoming accessible. We've grown used to the world wide web, but what are the implications of sharing a net that only covers a small local or regional area?
I don't know what this story is about, but there is a lawsuit in there somewhere.
Fuck systemd. Fuck Redhat. Fuck Soylent, too. Wait, scratch the last one.
It's good to see people doing stuff, but this article is a decade or two out of date.
Hams have been hooking computers to radios for a long, long time.
There are hundreds of pages on digital radio and sound card interfacing:
try
http://en.wikipedia.org/wiki/PSK31
http://hfradio.org.uk/html/digital_modes.html
http://www.tapr.org/packetradio.html
http://www.dxzone.com/catalog/Technical_Reference/Sound_Card_Radio_Interfacing/
The quality of reporting in this article really sucks. The printed circuit boards on top of the tins are not 'telegraph keys', they're the transmitters and the white box is the iPhone interface. Quite where the 'sodium clouds' come in I have no idea because in thirty years of ham radio operation I've never seen one, heard of one or used one to make a contact with a fellow ham.
Ganty
I went to a Maker Faire a few months back and started talking to some HAM radio operators. They told me that far from a dead activity, they have actually gone digital, incorporating the Internet to connect to transceivers for when they aren't able to have an antenna in thir back yard. One other technology mentioned was SDR, otherwise known as software defined radio. SDR means that the necessary hardware is simpler, with the majority of the signal processing now in software. There is an SDR app for the iPhone, but you need a piece of hardware that plugs ino the antenna and also plugs into the headphone jack of the phone. I haven't looked at Android, but I imagine you could use some form of GnuRadio.
Jumpstart the tartan drive.
In this application, the serial interface on the dock connector would not be sufficient. It's common to use a PC to implement ham radio modems via the PC's sound card. The radios rarely have built-in modems, and there are a lot of different digital modem protocols used on the ham bands for data, images, etc. New protocols pop up fairly often, and these days it's unusual to use dedicated modem hardware for this application instead of implementing the modem in software. Interface to the radio is via its analog microphone input and speaker output, or often via a line-level analog interface connector provided for connecting external modems.
Many radios have a serial port for controlling radio functions like tuning, and the dock serial interface would be useful for that. The actual data path would still need to go through analog I/O such as the headphone jack or line-level signals on the dock connector.
I would still be happy to see the sort of interface you describe for other applications, but this is complicated by Apple keeping the full dock connector interface specification under wraps, and only releasing it under NDA to companies that Apple deems worthy. Thus, companies like Belkin can crank out mountains of low-quality crap for the iPhone, yet an entrepreneur is effectively barred from marketing innovative hardware accessories for iPhones.
I was the guy who wrote this article. I have to say, I've had a few stories posted to Slashdot and it's always useful for feedback :) Just to clarify a few points though, in the picture, those little tin cans, Tumino actually did say they were telegraph keys. He had them on display next to an old antique one to show they're not hard to build. I guess the article was a bit babbly. It was written under a new column I started, basically just about people doing cool things with technology. I thought the ham radio guys were pretty cool, and I know that during the Arab Spring, when people were having their Internet shut down by governments, part of the care package released by Anonymous Operations taught people how to access the Internet over radio. So I thought this had some added relevance, since radio still does have some interesting uses when it comes to digital freedom, and you can do some pretty cool stuff with it. Also, sodium clouds do exist. They're pretty cool, actually: http://deep-red.sr.unh.edu/model/io/cloudescr.html
Amateurs have been doing this for a long, long time now (IE over a decade). This is not a SDR (software defined radio), but using a computer's audio card to encode and decode packet / APRS audio, which is essentially your old school modem. To be concise, the computer (or smartphone) acts as the TNC (Terminal Node Controller), which is connected to a radio via an interface that takes audio to and from the computer to the radio, with some method of telling the radio when to transmit (typically via an audio level threshold, but there are interfaces that allow the computer to explicitly control when the radio transmits). I own an AEA PK-232 Pakratt, which is a discrete, stand-alone TNC that goes between a computer and radio. Originally the computer was just the terminal, which connected to the TNC via a serial port. Now you can simply have the computer directly process / generate the audio using a sound card without requiring an actual TNC peripheral.
The "inventor" even states that there are multiple apps for iPhone available to do this - you just need a way to hook the audio up to a radio. Basically he created yet another custom hardware audio interface, and the writer of this story got all excited about it because it was news to him.
Look online, and you'll find dozens of designs for this exact thing. Here's a list of at least a dozen kits and pre-assembled interfaces for standard PC sound cards. Most of these should work with any smartphone with the proper 4 conductor 1/8" audio jack that cell phones use for both earphone and mic combined (whereas computer sound cards have those as two separate 1/8" connectors).
http://www.soundcardpacket.org/1cablekit.htm
That site is dedicated to the entire "computer as a TNC" concept, which is simply what is being down now with smartphones as well.
Better known as 318230.