Youtube comments of (@GBPPR2).

  1. Jack frost  I've had nothing but bad luck with those under Linux!  Everyone else seems to get them working except me.. LOL
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  2. Yes.. the Russian cavity bugs required thousands of watt of RF illumination power, that was their real drawback.  They'd actually cause electrical interference within the embassy.  These "new" bugs required very low RF power. I have an excellent documentary which talks about that Russian device on my backup channel: The Spying Game - "Walls Have Ears" (Complete)
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  3.  I believe you can... Radio Shack used to have a huge parts warehouse you could order anything from.. I think these antennas may be discontinued though.
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  4. dre8431 http://support.radioshack.com/support_electronics/doc44/44541.htm
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  5. Yeah, the lip should technically be removed, but that's usually too much work, and like you said, they'll still work and are basically free!
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  6. It has a slightly higher noise floor, between -70 and -60 dBm.  The full span mode is in a series of steps, which is annoying, but still usable. It is not synthesized, so the center frequency does drift a bit.
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  7. itakeyourphoto  Yes, the 1.7-4.1 GHz tracking generator idea appears to work, I switched to a Watkins-Johnson M1G mixer for better frequency response. Turns out you may need to tweak the 2050 / 321.4 MHz input signal slightly, say +/- 100 kHz, to take into account the slight misalignment inside the spectrum analyzer itself.  I'd keep them separate if you can, you want all the isolation as possible.
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  8. You'll have to order it off the Mini-Circuits website
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  9. Oh wow.. I haven't heard of that project.... Looks very interesting, and yes, most PLL use a very similar serial data stream, just that the registers tend to be slightly different.
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  10. Yeah, the triangle wave is 100 kHz. I chose it as it an easy frequency to make with that chip.. Yes, you could pull-down the module's bias pin in a high-SWR state with a simple transistor or op-amp comparator, but 800 MHz band isolators are easy to find and I'd just use one of those..
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  11. The ATtiny is configured as a pulse-position modulator at a pre-set ultrasonic carrier frequency, say 100 kHz. The audio from the microphone modulates the PPM and the output pulse train of the PPM toggles the gate of a FET to generate the (AM) backscatter signal when illuminated by a remote radar unit.  The audio is then demodulated as a 100 kHz FM subcarrier on that received (backscatter) signal.
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  12. Oh wow..  I hadn't seen you video until now.. good work!
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