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I built one to hook up to my MP3 server, and it's worked great. Now my server has a cron job to play the appropriate playlists at certain times of day. The other benefit is that it can do non-MP3 things, such as download the weather forecast and read it (using festival) to me. I also made a pretty simple web interface for when I need to pick songs to play or create a new playlist.

Here's a link to my model. I've been very happy with it. It took about 15 hours to put together (including time to learn to solder).

Ramsey Electroniccs is probably the best-known vendor of consumable FM transmitters, with power levels ranging from a fraction of a Watt (good for broadcasting MP3 to your boombox out on the patio), to 500W.

The local college station here broadcasts with effective radiated power of 150W, from a not-so-big tower on top of a 3-store campus building. I can recieve it quite well within a 10-15 mile radius with the radio in my car, and understandably-well for a few miles past that. I consider this pretty good.

Whatever anyone does who might be considering pirate radio, I can only suggest this: be considerate to your neighbors. Nothing will draw the attention of the FCC and corporate lawyers faster than stepping all over a commercial broadcast, overmodulation of your signal (you need a stiff, brick-wall limiter in-line before the transmitter, set up by someone with a clue), or distortion of your broadcast.

The latter troublespot, distortion, is likely to be physically dangerous to others: There's aviation bands at about 2x FM broadcast frequencies, and any malformed waveforms (harmonics) eminating from your antenna will show up in exactly this spot. This Is Bad. If you kill a the pilot of a Cessna because you feel like broadcating "good music" to the masses during bad weather, I hope you rot in jail for the rest of your life.

That all said, you really want to at least borrow someone well-versed in radio broadcast to help with the setup and calibration of your transmitter rig. As long as you're considerate of others, you may be just fine, broadcasting away for free...until, of course, a knock at the door signals the end of the party. ;)

This story peaked my interest and I headed over to Ebay to see what kind of radio stations might be for sale... you never know.

What I found instead was a Ramsey FM Transmitter (model number FM-100) that was currently at $349. Turns out that's way overpriced, considering Ramsey sells it for $224.95, unless this is the high-power version that Ramsey isn't supposed to sell inside the US -- in which case that might be an excellent opportunity for somebody in the US to get this one from a "third party" -- I'm not saying you SHOULD, just that you COULD.

Anyway, I thought this was really neat. Is it going to give you miles and miles of coverage? Heck no. But it's an all-in-one FM transmitter, and replaces a bunch of hefty equipment that I remember from my days in FM radio as a kid. Especially if this is the "overseas version", you could get enough coverage for you and your friends.... then you can head over to the FCC's site about LPFM (Low Power FM) to see if, through your school or something, you could get a LPFM license. Apparently they're pretty straightfoward.

This story peaked my interest and I headed over to Ebay to see what kind of radio stations might be for sale... you never know.

What I found instead was a Ramsey FM Transmitter (model number FM-100) that was currently at $349. Turns out that's way overpriced, considering Ramsey sells it for $224.95, unless this is the high-power version that Ramsey isn't supposed to sell inside the US -- in which case that might be an excellent opportunity for somebody in the US to get this one from a "third party" -- I'm not saying you SHOULD, just that you COULD.

Anyway, I thought this was really neat. Is it going to give you miles and miles of coverage? Heck no. But it's an all-in-one FM transmitter, and replaces a bunch of hefty equipment that I remember from my days in FM radio as a kid. Especially if this is the "overseas version", you could get enough coverage for you and your friends.... then you can head over to the FCC's site about LPFM (Low Power FM) to see if, through your school or something, you could get a LPFM license. Apparently they're pretty straightfoward.

I would highly recommend you take a look at ham radio and maybe Monitoring Times and Popular Communications magazines. Sounds like you might be a good cadidate for a radio hobbyist. Good luck!

Ramsey Electronics has a selection of AM and FM transmitters, either in kit form or pre-assembled.

On the main page is a blurb about their 35-Watt model, which would be sufficient for covering a small town.

There is an active community (or there was, on usenet) of people who modify their products for various things... it has all the smells and tastes of OSS.

I picked up their cheapest FM Stereo kit some time ago for less than $50, but never got around to completing it. IIRC, it was advertised to work at a few hundred feet, with several available hacks to double or quadruple that.

1. A scanner. I don't mean a paper scanner, I mean a scanning radio receiver. You could hear all kinds of cool s*** listening to the large number of cordless phones in the dorms.... Not to mention listening in on the campus cops.

2. A short-range FM Radio transmitter. I had the Ramsey FM-10 (go to Ramsey Electronics for details). You want one for "Part 15" operation. These are legal, not very expensive, and very, very subversive!

3. I'll echo a sentiment I read in another post.... Lots and lots of encouragement--the single most subversive thing there is.

Oh, and don't let her get a cordless phone unless it is digital and encrypted, 'cos there are guys like me on campus (See item 1 above. :-D )

• You can use any headphones that receive FM
• I can use a little pocket radio around the yard playing CNN
• Much more development effort and cost reduction goes into a mass market item than the big clunky "wireless" headphones
• It's "open source" (grin)

Bah! Anonymous cowards suck. What's so scary about using a pseudonym, anyway?

*sigh*

Anyway, you're wrong.

Not about the FCC rules, but about the fact that broadcasting an FM-10 (or an AM-1, which would be even more well-suited to the task) is illegal. It's not. An FM-10, when assembled according to instructions, puts out about 8 mw of power (see "FM-10 Myths") making it perfectly legal under Part 15 rules.

In conclusion: Don't spread FUD. Thank you.

The performance of a sound recording publicly by means of a digital audio transmission, other than as a part of an interactive service, is not an infringement of section 106(6) if the performance is part of ...a nonsubscription broadcast transmission.

Actually, like your cordless phone, the FM-10 broadcasts at powerlevels which don't require any license, not even the micro-licenses which have been proposed and defeated in recent years.

By the way, PBS and NPR are two of the biggest opponents of micropower radio. If it weren't for their efforts, we might have 100- and 1000-watt stations licensed all over America right now. Because I help run a pirate station here in Minneapolis, I'm not pledging to either PBS or MPR until they change their stance on this, and I encourage others to do the same.

Which is too bad, because Frontier House r0x0rz. :)

The statutory royalty rate for Internet simulcasts of FM radio broadcasts is only half that of Internet-only broadcasts. So couldn't any web station cut their royalties in half by spending $34.95 (plus shipping) to buy a micro-FM transmitter? Why not?

I don't know if these are the same ones you're talking about, but when I was a kid I built stuff using the kits from Ramsey. Ya know, cool stuff like FM transmitters and wireless microphones and what not.

My notion of GNU Radio would be simple and inexpensive free FM BROADCASTING. Of course, the FCC has issues with that... if you pay attention to the micropower FM scene, it's actually quite similar to what GNU stands for. It's about empowering people.

The catch is, it's pretty easy to screw up an adjacent station if your signal is screwy and out of spec.

The low-power FM movement is worth your attention- if you're even reading this article you probably 'get' the importance of micro/local broadcasting. It should come as no surprise that corporate radio has been using Congress and the government to try to stamp out even the possibility of people using local FM broadcasting to provide alternatives- it mirrors what other content industries have been doing with more Slashdot attention. In December 2000 Congress passed an appropriations bill with a rider that was snuck in to halve the number of low power FM licenses the FCC could legally issue. Not only was corporate radio behind this- NPR also supported the illegalization of low power FM broadcasting. McCain (R-AZ) has introduced a bill to counter this and support low power FM again. Furthermore, on February 8, 2002, the Court Of Appeals struck down language in this anti-LPFM act which had prohibited the FCC from issuing a license to anyone who had ever previously been involved with pirate radio. The court held that this was unconstitutional. (funny how both in the judiciary and Congress, these guys are forced to deal with all types of injustice and power grabs, not just the sorts that are close to the hearts of Slashdotters ;) )

These people are the other side of the coin: transmitters from microwatt to 500 watts and kits for all kinds of nifty things like subcarrier decoders, shortwave, the aviation band etc. I don't know anything about them but their catalog but it would make any true geek absolutely drool, with all the build-it-yourself devices to do arcane and amusing things, and the flashy computerised rackmountable transmitters. Too cool.

I bought a SoundFeeder SF100 from BestBuy for $10. It has a 1/8" plug for sound input (soundcard, anyone?) and a cig lighter plug to power itself. I replaced the internal antenna with a 1/4 wave piece of wire, soldered an old cig. lighter adapter socket I had lying around to a HDD power cable / fan adapter....

And now my computer directly powers my FM transmitter. Put a second soundcard in dedicated to the SF, and now I have XMMS crossfading through my playlist, all over the house.

$10 SF100
$9.50 Soundcard from compgeeks.com
$2? Cig.lighter splitter to cannibalize

Beats the hell out of the cost of the Ramsey FM25, which is bulkier and doesn't work any better without a seriously improved antenna.

I've found that a cheap FM transmitter coupled with a regular PC makes a great music delivery device. Ramsey Electronics, among other companies, make a variety of FM transmitters that can take the sound output from your computer, and locally broadcast it to any radio or stereo you have. You don't need any other special equiment, get your favorite mp3 playing app on whatever OS you prefer and you're ready to go. The quality isn't anything to write home about, but for the price and the ability to use all your existing equipment, I think it makes a great choice. Just think, you can "stream" to your clock-radio in your bedroom!

Another alternative for MP3's that I don't see mentioned often:

Ramsey Electronics has an FM transmitter which plugs in nicely to your computer. Then, any radio around the house can pick up your MP3s, including the main radio, and the headphone radio you have when you mow the lawn.

The only catch is that this transmitter is sold as a kit of parts, and you must solder the thing together. This makes it a "homebrew" radio which is legal to transmit onto the FM band. It works great around the house.

Not sure about the copper cube, but one of these might do well. http://www.ramseyelectronics.com/cgi-bin/commerce. exe?preadd=action&key=scrm1

You *are* missing something. Assuming that your server (or other machine with big hard drive full of MP3s) is in one room, and you have a stereo (or stereos) elsewhere, this device allows you to listen to your MP3s wherever you have ethernet (or wireless 802.11), *and* allows you to control those MP3s and view whats playing without having to run to the room where the computer is.

True, it has no functionality over a PC, but then again neither does a laptop or palmtop - people buy those not for the added functionality, but rather for the fact that they can be taken places where its not really very convenient to take a full PC. Like your living room, for example.

If this is what it appears to be - the most basic, upgradable option for those of us who have a network, a bunch of mp3s on a server, and the desire to hear them played in other areas of the house - then it is a worthwhile item indeed.

Of course, I've been using an FM25 transmitter from Ramsey Electronics to cover my section of the neighbourhood with MP3s, which is a seperate topic entirely!

Apologies if I'm restating the obvious, I figured rather than modding this down, I'd reply to it.

I just followed the Ramsey Electronics link in the main article, and they are all 1-shot-kits that I was recommending against.

I was about to post a link to a radioshack kit when I saw the AMAZING 500-in-1 Electronics Lab in a post on here from Usquebaugh. It's not cheap - $169.65 US - but if your kids take to it, it can easily be more valuable than a semester of math/science/computer courses in college.

If $170 is too steep the same site also has a page here starting at 50-in-1 for $20, 75-in-1 for $24, 200-in-1 for $50, and 300-in-1 for $70. (Note: based strictly on the pictures the 200-in-1 looks better than the 300-in-1?? The 300-in-1 seems to blow alot of space on the switches/dials/speaker, and what is the large white non-descript area in the middle?)

Ten-Tec has some decent radio kits. For $24 you can get the 1054 which is a stripped-down regen shortwave receiver. For $69 you can get the 1253 which is a complete regen receiver. Either will provide decent listening to both ham and shortwave broadcast stations.

Ramsey kits are ok, but you need to read carefully. For example, they advertise kits like the SR2 with a photo of it in a case. The case is a $14.95 option and you still don't get a speaker.

As for building ease, I can't really comment. The only recent kit I've built is the Ramsey SR2. It was easy but time-consuming and a bit boring, as I've soldered thousands of components in my time.

Nuts & Volts magazine is a good source of ads for kits.

I'm not sure how much you can learn from one of these kits. They tend to not have much in the way of experimentation. You build the kit, play with it for an hour or two, then stash it on a shelf. If you're going to go the kit route, I would start with a simple blinking LED kit or something to learn soldering, then maybe a decent radio kit that you'll actually be able to use.

If you want to get the kids interested, I would go to Radio Shack and dig around in the back. There you will find some dusty books from the Engineer's Mini-Notebook line ($1.99). They have easy explanations, circuit diagrams, and lots of experiments to try. They don't make it trivial to find the parts and you'll be spending quite a bit of time prowling Radio Shack parts racks, but it's worth it. The kids will get to do some of the design work themselves.

Call me paranoid, but I think the riaa is making these ridiculous statements to see what the reaction is from various parts of the net before making their real move. Hey riaatards! Kiss my ass!

BTW: Ramsey Electronics has a kit for you to build that will hook up to your computer and broadcast your MP3's for you! Enjoy!

Ramsey explains why Americans can't buy these terrorist tools. No shit.

Can't get to the website due to errors over there, but if this kit is based on the BA1404 chip like the Ramsey FM10 (which, for this price I think it has to be) you may have serious problems receiving what this thing puts out on many FM receivers. The BA1404 uses a tank circuit (an inductor and a capacitor) as the part that sets the frequency, and this can drift really badly. Many FM recievers today are PLL based (if it has a digital display, it probably is) and can't tune in an analog sense. If the signal drifts off of the FCC "channel" (they go in 200KHz increments, starting at 87.9 up to 107.9), many receivers won't, and if they do at all you get a really noisy signal. An FM discriminator can pull in a signal a few KHz, but they are generally designed to work within the frequency specification that FM broadcasters are mandated to follow by the FCC, which is *much* smaller than the frequency precision an L-C tank will give you.

There are FM transmitters out there that don't suffer from this problem- they use a crystal controlled PLL circuit to set the frequency, Ramsey sells one. But it is much more complex, and more expensive (I think Ramsey's is about $150)

Well, you can broadcast a signal for a lot less than some of you people think - the hardware to take a stereo ouput to the air is under $65. Hook that up to a computer with WinAmp (or XMMS ;^) and you have yourself your own private station.
One company offers kits for this stuff online, I have a few links:
Ramsey Electronics
a specific kit

-Smitty

Well, you can broadcast a signal for a lot less than some of you people think - the hardware to take a stereo ouput to the air is under $65. Hook that up to a computer with WinAmp (or XMMS ;^) and you have yourself your own private station.
One company offers kits for this stuff online, I have a few links:
Ramsey Electronics
a specific kit

-Smitty

It would a bitch to set up with a laptop, though. Software is probably more practical there.

Remember: If this company were based in the U.S.A. they would have been raided and shut down under the same laws Ramsey Electronics was. I'm sure the g'bment would love to confiscate a bunch of these puppies!

I hope a similar outcome occurs in the Ramsey Electronics raid case. Makers of electronic kits are scarce enough w/o the feds having a fit of paranoia. You can help by filling out the form if you own or would like to buy any of the small FM 'wireless mics' they used to sell. Bastards.

<PARODY>Look! K-Mart is selling TELESCOPES!! Those can be used to spy thru people's windows!!! RAID!!!!!!!!</PARODY>

Here's a link to Ramsey's website
http://www.ramseyelectronics.com/

Will transmit both sides of telephone conversation up to 1/4 mile! Very small size fits anywhere in phone or on phone
line. Connects in series and draws its power from the phone system - no battery needed. Great for roomful listening (a
speakerphone without the wires!) or seeing what the kids are up to! Output tunable from 88 to 108 MHz. Can be received
on any standard FM receiver so anyone can listen. Size: 2"w x 7/8"h x 5/8"h.

Perfect video transmission from a transmitter you can hide under a quarter and only as thick as a stack of four
pennies - check out the size compared with a penny! Transmits color or B&W with fantastic quality - almost like a
direct wire connection to any TV tuned to cable channel 59. Crystal controlled for no frequency drift with performance
that equals law enforcement models that cost hundreds more! Basic 20 mW model transmits up to 300' while the high
power 100 mW unit goes up to 1/4 mile. Units run on 9 volts and hook-up easily to most any CCD camera module. Any of
our camera modules have been tested to mate perfectly with the Cubes and work great with solid, trouble-free
operation! Fully assembled and tested - just hook-up power and you're on-the-air with a killer system!

Check out our nifty wall clock! Uses our popular "Cube" video transmitter and one of our quality B&W CCD cameras, all
expertly and cleverly hidden in the everyday object. The camera and transmitter operates on a standard 9VDC battery,
and the clock requires one standard AA cell for the quartz movement. Of course, the clock does operate as a fine time
piece! All units transmit on cable channel 59, easily received on any cable-ready TV set. Completely assembled,
wired, tested, and ready to hang.

Check out our smoke detector! Uses our popular "Cube" video transmitter and one of our quality B&W CCD cameras, all
expertly and cleverly hidden in the everyday object. Units run on a standard 9VDC battery. Please note, the smoke
detector does not function as a operable smoke detector! Use this for your video projects, but get a real smoke
detector so your house doesn't burn down! All units transmit on cable channel 59, easily received on any cable-ready
TV set. Completely assembled, wired, tested, and ready to hang.

Disguised Wall Clock Video Camera System
Disguised Smoke Detector Video Camera System

Now I'm not going to poke fun at their "hide it under a stamp" microphone. It's an item that has some legit as well as non legit uses, like most tools. The way they advertise it is questionable, but the item itself is useful.

However, they way they advertise their products strikes me as a deliberate attempt to attract people with less than honorable motives.

Unfortunately, a some point in time, a decision is made that a tool is dangerous enough that it's risks outweight it's benefits. What side of the line these tools are on is up to you to judge, and to lobby your lawmakers with. However, the way Ramsey electronics portrays some of their inventory no longer leaves a doubt in my mind on what side they take.

Disguised Wall Clock Video Camera System
Disguised Smoke Detector Video Camera System

Now I'm not going to poke fun at their "hide it under a stamp" microphone. It's an item that has some legit as well as non legit uses, like most tools. The way they advertise it is questionable, but the item itself is useful.

However, they way they advertise their products strikes me as a deliberate attempt to attract people with less than honorable motives.

Unfortunately, a some point in time, a decision is made that a tool is dangerous enough that it's risks outweight it's benefits. What side of the line these tools are on is up to you to judge, and to lobby your lawmakers with. However, the way Ramsey electronics portrays some of their inventory no longer leaves a doubt in my mind on what side they take.

Disguised Wall Clock Video Camera System
Disguised Smoke Detector Video Camera System

Now I'm not going to poke fun at their "hide it under a stamp" microphone. It's an item that has some legit as well as non legit uses, like most tools. The way they advertise it is questionable, but the item itself is useful.

However, they way they advertise their products strikes me as a deliberate attempt to attract people with less than honorable motives.

Unfortunately, a some point in time, a decision is made that a tool is dangerous enough that it's risks outweight it's benefits. What side of the line these tools are on is up to you to judge, and to lobby your lawmakers with. However, the way Ramsey electronics portrays some of their inventory no longer leaves a doubt in my mind on what side they take.

Disguised Wall Clock Video Camera System
Disguised Smoke Detector Video Camera System

Now I'm not going to poke fun at their "hide it under a stamp" microphone. It's an item that has some legit as well as non legit uses, like most tools. The way they advertise it is questionable, but the item itself is useful.

However, they way they advertise their products strikes me as a deliberate attempt to attract people with less than honorable motives.

Unfortunately, a some point in time, a decision is made that a tool is dangerous enough that it's risks outweight it's benefits. What side of the line these tools are on is up to you to judge, and to lobby your lawmakers with. However, the way Ramsey electronics portrays some of their inventory no longer leaves a doubt in my mind on what side they take.

and take a look at this


"Check out our smoke detector! Uses our popular "Cube" video transmitter and one of our quality B&W CCD cameras, all expertly and cleverly hidden in the everyday object. Units run on a standard 9VDC battery. Please note, the smoke detector does not function as a operable smoke detector! Use this for your video projects, but get a real smoke detector so your house doesn't burn down! All units transmit on cable channel 59, easily received on any cable-ready TV set. Completely assembled, wired, tested, and ready to hang."

Screams "Surreptitious Surviellance Device" as far as I see.

http://www.ramseyelectronics.com/cgi-bin/SoftCart. exe/scstore/sitepages/hobby/fedpage3.htm ?L+scstore+fxwm3054+947117653

Having said that, I agree with what you're saying. If the knowledge comes entirely from open, public sources, then there does seem to be something unethical about closing the compilation of that knowledge off and keeping it for commercial gain. It's about as sensible as AOL trademarking "You've Got Mail".

P.S. ObOffTopic footnote: If you're into electronics, check out the following websites for a scary note: Ramset Electronics, 2600 and CyberSKIP. There's something definitely not OK going on.