|
Sup HP48 buddy. I only had the HP48G+, no expansion slots for me. I still have mine and use it if I am actually going to do calculations at home. The buttons are so positive in their feedback. The whole calculator is built like a tank. The worst thing about them is the garbage collection that stalls out the calculator. I find myself using the emulated HP48 on my phone while at work, since I don't have room for the real thing in my pockets. I really miss the buttons on the phone though.
|
#
¿
Sep 3, 2012 03:23
|
|
|
|
| # ¿ Apr 24, 2024 19:23 |
|
|
 This is a mercury arc rectifier/valve. In 1902 and on for a shocking amount of time, this was the way you turned alternating current into direct current. The most common use of these would have been turning the AC from the power grid into the DC used by most subway or other transit systems as the DC motor was and still is, for the most part, king. Nowadays, we have tiny integrated circuits that can do this for normal household items. Every wallwart, power brick, and power supply in TVs and computers does this with much smaller, more efficient means. But even recently, as of 2004 (according to Wikipedia), the metal box version of these was used to turn high voltage AC into high voltage DC. Now with solid state electronics that can withstand kilovolt switching, these are effectively obsolete (as of 1975, again according to Wikipedia). Look at that wonderful light, listen to that wonderful 60Hz hum https://www.youtube.com/watch?v=KGb-nUK41tc: that's  . Ponder if the UV burned skin, cataracts, and possible mercury exposure is worth it. I desperately want one of these.
|
|
#
¿
Jun 28, 2013 04:45
|
|
|
Three-Phase posted:As far as power semiconductors go (diodes, SCRs, IGBTs), depending on the semiconductor not only kilovolts, but kiloamps of current. (I worked with SCR pucks that could handle around 1500 amps at several hundred volts.) DC transmission, once a mad pipe dream of some rear end in a top hat named Edison, is becoming a reality because we can actually do useful things with DC now. Changing DC voltage is now a matter of solid state voodoo versus having to use two DC motors of different voltage coupled together mechanically. It will have advantages over AC such as no AC line losses and doing away with syncing issues between various grids. Also less wire, as I have heard of them using single conductors at 1MV and the earth as the ground. Smaller wires, less wires because higher voltages and less losses? Yeah, I think the future is going that way. So, Edison, you lousy shitbag inventor, your mad dream of DC is comin true, although AC is still better for a lot of things.
|
|
#
¿
Jun 29, 2013 19:17
|
|
|
Non Serviam posted:
http://dx.com/s/cr123?category=400
|
|
#
¿
Aug 11, 2013 18:34
|
|
|
Slanderer posted:Dear god, do not buy batteries from Deal Extreme. This is a very bad idea I've bought many batteries from DX. It is a bit of a gamble sometimes, but generally I've had very good luck. What harm would a little fire do to your obsolete ancient metal camera? Note, I've never had a cell start on fire. (USER WAS PUT ON PROBATION FOR THIS POST)
|
|
#
¿
Aug 12, 2013 06:13
|
|
|
Dewgy posted:OK, really? A can opener? It really is. The only good thing philips screws are good for is drywall because you want it to strip out. It is probably the worst screw design there is. At least flat blade, or standard or slot, looks somewhat nice if external and can be operated with just about anything flat. They should be obsolete but people still loving use them. Robertson has been around for over 100 years and is better than any screw type there is, without getting into cap screws. I would love to never have to use a philips or slot screw again.
|
|
#
¿
Jun 18, 2014 04:50
|
|
|
Christmas Present posted:tiny 80x400x600mm phone fit perfectly. That's a big loving phone. I think you missed a decimal point. https://www.youtube.com/watch?v=27aVPqpnL7Y
|
|
#
¿
Feb 18, 2016 00:11
|
|
|
|
| # ¿ Apr 24, 2024 19:23 |
|
|
mobby_6kl posted:poo poo, forgot CF cards were still a thing, it seemed everything short of top-tier SLRs moved to SD by now. You could definitely stick a CF card in there, or even a couple of them, actually. And yeah, it's just for sentimental value or making what you already have work. SD cards are still slow as poo poo compared to CF and the new 1DX MK II uses CFast 2.0, which is basically a SATA drive in the Compact Flash form factor. When you in the high end, SD won't cut it at all.
|
|
#
¿
Mar 15, 2016 01:00
|
|