Scrambled Regs, and hold the ham

[jnr0104]

Well, glad they work. You know of course once you plugged them in, your radio became the target for the NK missle test that supposed to be coming up soon, may want to fedx them to DC ASAP !

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Well, glad they work. You know of course once you plugged them in, your radio became the target for the NK missle test that supposed to be coming up soon, may want to fedx them to DC ASAP !

As long as they aim it at me I'm safe. If they aim it somewhere else then the odds of it hitting here are higher I think.

Still doing some testing and research with this EN37 voice inversion setup. It's using a fixed split band inversion method, meaning it takes the audio and inverts everything above and below a specified audio freq and inverts the higher and lower separately, then combines both and transmits them as one. At the receiving end it breaks them into two streams again, uninverts them, and combines them for output to the speaker as plain voice. This method is supposedly a little better than straight baseband inversion, but I captured the inverted speech with a Baofeng, saved it as a .wav file to my computer, and was able to decode/reinvert it fairly easily with a public domain software utility found on the web. The audio clarity isn't good, but it is possible to understand the conversation. Disappointed, but not too surprised, that it was relatively easy to do. That said, I did need to set up the computer, attach the speaker/mic cable, start the recording, and I knew what freq to listen on.

Initially my thoughts are that if you keep your transmissions short and change freqs after every short exchange, you're probably safe from any (non-govt) bad guys from decoding your conversation in real-time. Short transmissions being under 30 seconds, or up to a minute maybe. Whether using a hardware or software descrambler they'll need a few seconds to find your freq, then time to adjust their settings to understand you. If you stayed on the same freq and used the same inversion settings, they could listen and understand you all day without having to change anything on their end. So keep it short, and keep changing both freqs and inversion settings.

Or, they can scan entire frequency band(s) and record everything that breaks squelch, and if they catch some voice inversion communications then use software to decode it. All that's required for that is to play the recorded transmissions in a loop and adjust the software settings until the voices are understandable. That's not real-time, but it doesn't take very long once they have it on their computer and start adjusting the settings in their descrambler software either.

Have a couple ideas on how to make things tougher for any bad guys, should be able to test one this weekend and will post the results (good or bad).

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Bah! Tried setting this up for half-duplex operation between the house and mobile, each transmitting on one freq and listening on the other and the freqs reversed for both radios, with a different scrambler setting for the transmit/listening sides. Nope, looks like when the scrambler is on it only allows a single scrambler code, not one for xmit and one for receive. Damn shame, cause the 2900R supports that for CTCSS/DCS tones so I thought it might for the scrambler setting too. Could be I'm missing something in the programming, hard to find instructions for something that's unsupported. Half-duplex with one scrambler setting is slightly better than simplex since it requires an eavesdropper to find and switch freqs with us or miss half the conversation, but better would have been diff freqs and diff scrambler settings for each. Still experimenting with options, but have to keep it easy for the Mrs to operate - or anyone under stress.

And, about to pull the trigger on a SONY ICD PX333 Digital Voice Recorder for recording our own transmissions for descrambling practice, and (placed by the scanner speaker with VOR on) to help ensure we don't miss anything important when scanning for intel in a SHTF situation. After playing with voice inversion for the past week, I don't want to go back to being just a "casual listener" that's easily defeated by any shady, lowlife S.O.B. that tries to use a voice scrambler in my AO. Oh wait, nevermind that last part

[jnr0104]

Well hoping you check in today, if not I guess we will know the NK missle nav system is better that projected.

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Still here. NK rocket launch was successful, just hope they can use their satellite to rescue that poor Nigerian astronaut stuck up there...

[jnr0104]

LOL!