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Audio Tape, first thoughts:

Wow. Nice find on the mp3. Thank you very much. I've listened to it through 4-5 times now, with some pauses, to listen to a couple of areas over and over. Here's what I know:

Most likely there WAS a shortwave recording being made here. The "Snowball" net station is a computer voice, automated. The PSSSST sounds heard throughout the tape are packet signals. They are most likely 9600 baud packet bursts. As an explanation, packet is a digital signal, usually data that has been processed through a device called a terminal node controller (or TNC) or some other modem-like device that takes the data and sends it out via radio. There is a type of error checking in the headers that allows for the data to be resent, IF the receiving station is active and talking back. I did NOT hear that secondary response, so this data was one way apparently. One other rather important aspect to this packet signal, the FCC restricts the use of high speed digital signals to higher frequencies, especially with us Hams. That is, due to the bandwidth requirements of such a signal, and HF radio (which is between 2-30 Megahertz) usually is limited to 300 or 1200 baud packet/FSK/other types of digital signals. Above 30, however, 9600 baud is not uncommon and is used as a reasonable data transfer speed at those higher frequencies. I have personally USED 9600 below 30 Mhz with the military, so I know it done sometimes. It's not extremely reliable at long distances however, due to atmospheric noise, like lightning strikes and whatever other random noise patterns you can hear in such a receiver. If the communication is CLEAR, then it is no problem. Further, the military isn't really limited on "bandwidth" technically, and even though they still must follow certain rules when it comes to radio transmissions, those rules are ignored if a mission is essential. (I've personally ignored a few rules, when it come to accomplishing a mission.)

In the background, in at least two places on the tape I heard a morse code signal. It is an automated signal, and was at around 30 wpm, which is much faster than my rusty mind can copy. I'll have to slow the tape down to get it better, but I will. It is down in the noise level, but I copied a couple of letters out of the signal. One of the was the letter S. I think the other was I. However, both times, it was over ridden by either voice audio or packet bursts, so I can't quite pull it out of the mud. I have sent myself the file at home and will work on this in the next few days and see if I can't get more information out of it.

The answering station is a male voice (not computer generated). No identification. Sounds... well, semi-professional. It DOES sound... "faked" to me. However, people who aren't normally operating a radio all the time tend to "sound fake" anyway, when they key a microphone. They are usually thinking about "all those people that will hear me, so I better not screw up"... thus, psychologically, they tend to "act" when on the radio.

At the end of the computer voice, there is a set of tones that are transmitted. Those tones are sync tones. I do not want to say what those sync tones are associated with here in this forum, but I am reasonably certain of their origin. I will verify that sound as soon as I can, and if I can verify it, I will tell you.

Whether this is "authentic" I don't know. Can anyone, perhaps the person that posted the link, get me in contact with the original person who recorded this tape? Or has HE not come forward either? Who is this "ham radio club"? Does anyone know? Does anyone know where ANY of this originated (the original sites that posted all this in the first place that started all this)?

The only way to honestly get to the bottom of a story is to go to the source. I think I'm qualified to verify whether this is a real tape, if I can talk to the original source. (It sure helps being a real communications person, doesn't it? :) Not to mention being an amateur astronomer!)

Give me a few days to work on this, and I will see what other tid bits I can pull out of the noise level.