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"Ian Field" <gangprobing.alien1@virginmedia.com>: Jun 21 07:33PM +0100 <oldschool@tubes.com> wrote in message news:7lsikchkjfl0o8e6644nhnvb04d53nc1k0@4ax.com...   > All semiconductors need special handling. Usually I just wet my hands > and ground myself. That is plenty. Wet hands cant cause static > electricity.   Wrong - your hands are essentially wet by default. Wet hands simply provide a lower impedance jump off point for that fat blue spark.   Working on a PC - I rest my bare elbow on the metal case so I'm at the same potential as what the PC thinks is earth. Some people insist on unplugging the mains - but it makes no difference from the ESD point of view if you do it properly.   Handling individual ICs, I breathe on them so the slight humidity provides a leakage path between the pins. I always plant my hand on the anti static mat before putting the chip down to make sure I'm at the same potential as where I'm putting the chip. Deploying the part is same as working on a PC - touch the ground plane while introducing the chip to its socket.

whit3rd <whit3rd@gmail.com>: Jun 21 04:55PM -0700 > On Tue, 20 Jun 2017 20:16:48 +0100, "Ian Field"   > All semiconductors need special handling. Usually I just wet my hands > and ground myself. That is plenty.   Not sure about the 'wet hands' part (your hands have lower skin resistance than a ground strap), and the 'ground myself' is likewise a problem. We all have to unclip from the leash at some point.   Installing RAM, I generally unseal the package, then hold onto the computer chassis with my left hand while installing the module with my right. Earth ground is not a requirement, just that the conductive packaging, the installer, and the computer's groundable parts are all at the same potential. If you have groundstrap and conductive mat, you STILL need also to ground the computer. Sometimes, this is done with a dummy cord, ground-only, to the power supply, but that's just SO ugly: a power cord that doesn't connect power !!ick!!

"Ian Field" <gangprobing.alien1@virginmedia.com>: Jun 22 05:07PM +0100 "whit3rd" <whit3rd@gmail.com> wrote in message news:08db9c34-ec80-45e9-a6a2-d84bd5e19039@googlegroups.com... > power > supply, but that's just SO ugly: a power cord that doesn't connect power > !!ick!!   You didn't change much from what I said.

frank <frank@invalid.net>: Jun 22 11:47AM Hi, I already know the answer but we never know if anyone out there can make miracles :) I've been given a dead USB drive, in my linux laptop is identified as usb storage device but it fails to read (probably) the capacity and the usb stack keeps on resetting the device. It's not possible to open it, looks like a small solid plastick stick with metal tabs embedded on one side. It's just a bit longer than the typical usb slot. I tried heating and freezing it, just in case it was some temperature sensitive fault, but behaviour never changed. I don't think there's a way to expose the actual NAND-flash chip and read it separately, but I'm asking the expert here :) Did anyone ever found a way to open (or otherwise read) these little data killer devices? Thanks   Frank

"Ian Field" <gangprobing.alien1@virginmedia.com>: Jun 22 05:04PM +0100 "frank" <frank@invalid.net> wrote in message news:oiganu$kjc$1@dont-email.me... > Did anyone ever found a way to open (or otherwise read) these little > data killer devices? > Thanks   The only USB HDD I have any experience with is a USB external - it came with a special Y cable with 2 plugs so it could pick up enough current. Only 1 plug has signal lines.   Not tried it myself - but someone on a forum was complaining they had to clonk the drive on the desk to get it to spin up. They were using a normal single plug lead.

"pfjw@aol.com" <pfjw@aol.com>: Jun 22 07:55AM -0700 All:   Just got an e-mail from Mouser that some parts I had ordered in the past were about to be discontinued (as obsolete) by the manufacturer.   Few suppliers bother with this level of service.   Peter Wieck Melrose Park, PA

rickman <gnuarm@gmail.com>: Jun 22 11:44AM -0400 > All:   > Just got an e-mail from Mouser that some parts I had ordered in the past were about to be discontinued (as obsolete) by the manufacturer.   > Few suppliers bother with this level of service.   Actually nearly all the top tier distributors do that. I get notices when they change the way that install the chip in packages and all manner of similar notices from Digikey, Arrow and Avnet.   --   Rick C

bo.forsberg@gmail.com: Jun 22 07:30AM -0700 According to the Husqvarna patent, the signal should be 40 Volt peak-to-peak, each group of pulses is repeated at approx 80 Hz, the leading pulse is 100 microseconds and the following data pulses are 50 microseconds. The output stage in the charging station is a push-pull stage driving the pulses 20 volts in one direction and then 20 volts in the opposite polarity, creating balances pulses at 40 volts peak-to-peak. Acc to the patent the maximum pulse current is about 2 amps. Then of course the patent is wide enough to accomodate similar solutions, so the values I have given are not necessarily those used in practice. However, because people can trace the signal with an old AM radio, the pulses would have quite a lot of overtones which indicate short pulses as described in the paten. Unfortunately I have given away my old oscilloscope years ago, otherwise I would be lying in the grass analysing the signal....

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