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"Thanks to the advice of fellow readers from a previous Ask Slashdot, I now have a PC system optimally configured to produce professional on-air radio programs" Hmmm... I remain skeptical, esp. when you're seeking advice from Slashdot. To your question, no, you're not going to use Skype or VOIP for a "professional" broadcast, for any of a dozen reasons. As noted, you need a Telos Zephyr or similar product. There are broadcast quality units designed to transfer audio back and forth over an IP connection, but Skype isn't it. Don't waste time here, check out a few radio trade magazines. And, uh, "professional" is much less about gear than about talent and proven broadcast skills.

You actually have a couple of major problems. There have been some fairly exhaustive tests done in the audio realm, and they have found a couple of things.

The first is that the specific brand that works best will vary from one CD burner to another. The only thing that you can do is buy a lot of samples and try burns at different speeds and with different brands until you know what gives you the best results.

As noted, slower burns usually are better, but the optimal speed will vary too.

The other problem is that manufacturers change their formulations from time to time. You of course have no way to know this, but may find that the media that worked great last month suddenly has problems.

Another test can be found here.

The previous poster is correct. There were actually two tones (853 and 960 Hz) which were broadcast at the same time for 22.5 seconds. By using two tones it prevented false detection. Usually. I built more than one EBS detector during that period with a couple of Tone detectors (NE567 if I remember correctly) and an and gate and a 555 timer to not alert unless the tone was on for more than 10 seconds or so. This was primarily used in later years for local emergencies such as tornadoes. However, for nationwide emergencies another system was used.

Each station had a "big red envelope". The station I worked for had it at the operator position in the main control room. Digging around the internet I found this site which has a picture of an envelope from 73. I remember the newer ones (about 1991) being better printed, but about the same. The envelopes were sealed and were not to be opened unless the station received an EBS message via teletype which needed to be authenticated. This envelope was replaced on a regular basis.

At some point during the period I was around the station I asked the owner about the envelope, and he related the story about the February 1971 activation. Evidentally he was on duty when the message came in. (Looks like there's a copy of the message up on this site). He opened the envelope and checked the authenticators. Now you have to realize that everyone pretty much knew that the only likely reason for the nationwide system to be activated was nuclear war. Saying that he was rather worried by this message is an understatement. I can't remember if he complied with the warning or if it was called off fast enough that he didn't have to, but I do remember he was either ready to shut down or did.

If you google for "1971 EBS Activation", You will find some other stories about this event.

"HD" Radio (formerly known as IBOC, or In Band on Channel), is an inferior technology which many have found less than awe inspiring. It's adoption in the U.S. is the result of politics and money, not technological superiority.

One reviewer above described IBOC thus: "Let's start with audio quality. It's my opinion that the current 96kb/s codec is incapable of reproducing even a simple male voice without generating objectionable artifacts. It gets worse with music. On the classical cut the strings were thin and harsh. For those of you who are broadcasting contemporary formats, the codec removes sibilance unnaturally, changes the timber of symbols and makes back up vocals strident. This is not CD-quality by a long shot. In fact, during my listening test I found that our station's plain old analog signal sounded better than the 96kb/s codec."

At the same time that the U.S. has locked themselves into IBOC, the rest of the world has been moving ahead with Eureka 147 DAB, a purely Digital technology without the legacy concerns. Fifty countries and counting, with DAB building steadily, especially in Europe.

"HD" Radio (formerly known as IBOC, or In Band on Channel), is an inferior technology which many have found less than awe inspiring. It's adoption in the U.S. is the result of politics and money, not technological superiority.

One reviewer above described IBOC thus: "Let's start with audio quality. It's my opinion that the current 96kb/s codec is incapable of reproducing even a simple male voice without generating objectionable artifacts. It gets worse with music. On the classical cut the strings were thin and harsh. For those of you who are broadcasting contemporary formats, the codec removes sibilance unnaturally, changes the timber of symbols and makes back up vocals strident. This is not CD-quality by a long shot. In fact, during my listening test I found that our station's plain old analog signal sounded better than the 96kb/s codec."

At the same time that the U.S. has locked themselves into IBOC, the rest of the world has been moving ahead with Eureka 147 DAB, a purely Digital technology without the legacy concerns. Fifty countries and counting, with DAB building steadily, especially in Europe.

And by the way: when running perceptual tests, whether it's wine tasting or audio equipment, you need to do an "AAB" test. Most comparisons are "AB" comparisons where you tell the subject: "here are two different samples; which one is 'better'?" Telling the subject to expect a difference will skew the results. The fix is to present the subject with a control signal, and then two test signals (in randomized order), one of which is identical to the control (i.e. either "AAB" or "ABA"). Then see if the subject can do better than random chance in identifying the "B" sample.

Check out the Portable People Meter from Arbitron. It can recognize subaudible watermarks in music including over radio, Musak, and even some streaming audio compressions. Arbitron uses it for ratings purposes.

Of course, then there is IBOC from Ibiquity which is an on-channel digital enhacement for AM and FM signals, part of which could be used for datacasting, as part of most DTV signals will.