It is currently 20 Sep 2020, 14:57

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Posted: 24 Jul 2020, 17:54 

FWIW, i have accomplished a "proof of concept" by successfully decoding "something" using an RF capture i made with a LimeSDR (USB version).

This process required nothing too complicated. Following internet instructions for installing LimeSDR on ubuntu, then ld-decode on ubuntu, and using "pothos flow" (a visual SDR block flow tool) to capture an rf file. Happycube added the compatibility for the file type (float32, thanks). I only have "broad strokes" knowledge of all the concepts, so it could only improve from here. This setup can be obtained with zero soldering. EDIT: [I did have to remove one component from the limesdr board to improve HF performance, this can be done with a screwdriver]. I bought everything, hooked it up, and fiddled with the GUI settings of Pothos Flow for the SDR until i saw something in the ~7Mhz range.

While i realize for an actual archive capture, you would want to use the domesday duplicator board, for doing comparisons and tests, or to get your feet wet, this setup might provide a means to do that. the "domesday duplicator" is better and will provide the most fidelity, but this is an "off the shelf" solution that is available to anyone hesitant to put together the board.

I believe that the LimeSDR *may* be overkill at this point, because there are now cheap off the shelf frequency multipliers (shifter?) available ( Using such a device, you could use a cheaper SDR, and then just divide the signal in pothos flow.

DISCLAIMER: I can not confirm yet that this is a "full working solution". The "Ruckus" disc is in horrible shape, nothing in the setup has been optimized. I think that the capture the picture above is taken from, doesn't have a strong enough signal in the EFM, and possibly the analog audio.

Anyone reading this that has SDR knowledge, let me know. I literally just fiddled around with things until i got something ld-decode would accept. When i raised the gain past ~43 for the SDR, the signal actually disappeared!


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Posted: 26 Jul 2020, 19:11 

The V2600 is really a CLD-S201 with a serial port. If you get a good deal on it and it's fixable, it's still nice :)

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Posted: 30 Jul 2020, 17:15 

Had this happen to my dreamcast psu. If you're handy with a soldering iron then it shouldnt be too difficult to repair. I would suggest scraping back the trace to copper and solder a thick piece of copper across the break. I usually strip a coax and use the copper. Epoxy the board before you solder for added strength.

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Posted: 25 Aug 2020, 22:58 


I was waiting for someone more knowledgeable to respond, and they can correct me if i am wrong.

While the spec says the highest frequency is 9.31Mhz (or whatever it is), happycube once told me you needed about ~12.5Mhz of bandwidth, minimum, for the captures. I don't know why that is the case, but that is what i recall (iirc).

Nyquist-Shannon states the minimum, but that is the minimum with the most quantization noise/error. You can't go with the 10 bit 14.4MSPS mode, because it isn't high enough. period. So that leaves you the 2 8 bit modes. The higher msps will get you less quantization noise/error, so i'd go for that.

Just make sure your disk is fast enough to save it.
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