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Show HN: PunchCard Key Backup

pckb -- backing up 128 bits into physical medium. Contribute to volution/punchcard-key-backup development by creating an account on GitHub.

For example, the 128 bit number represented in hexadecimal as d74ae47dc6f599d3f9cb847bd77d6b7c, can be backed up as the following standard (CR80 ID) card sized aluminium sheet, which can then be put into a safe place: using the self-contained HTML at the link above ( https://volution.ro/pckb), either by entering the data manually, or by generating random data, one can get the hole punching pattern;(this whole procedure is described in the help, and you could consult it for more details;) from the same link above, or from here, one can print a standard (CR80 ID) card sized stencil, to be used as a guide for the hole punching; a small sheet of aluminium; (I've used a 0.5mm thick one I've bought from the hardware store for ~4 EUR;) a punch tool, used to mark (with the help of the stencil) where the holes should be punched; a small drill, used to actually punch the holes; (I've used a 1.00mm drill bit adapted to a standard screwdriver;) a cutter, to cut the aluminium steel sheet to the standard (CR80 ID) card size; (I've just used a ruler, and passed the cutter multiple times over the aluminium sheet, and in the end, it passed through;)(obviously, one can just use a wood plank, nail, and rock;) :) use the same self-contained HTML at the link above; make sure the checkboxes follow the punched holes pattern (for the key); check that the CRC checkboxes match the punched holes pattern (for the CRC); recover the base 10, hexadecimal, or text representation of the backendup information;

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