Design

Rules of thumb for power transformer current rating - derivation?
I have this document: http://www.audiofaidate.org/it/materiale/20_020_020_001_PowerTransformer_FilterRatings.pdf which gives rules of thumb for sizing power transformers for certain DC output requirements. It says there are plenty of references for the derivations of these rules available - but I can't find ... 22 Jan 2010 19:44

Capacitors and ESD
Are capacitors ESD sensitive? Please explain. Ceramtic? Tantalum? I know that some of the ceramic caps that I am working with are rated at 25 volts. An ESD zap can be multiples of 1000 V. I believe that the capacitors are ESD sensitive because I will exceed the max rated voltage. Is this true? Thank ... 22 Jan 2010 20:51

STmicro acceleration/magnetic sensor LSM303DLH == LIS331DLH + HMC5834?
Just had a look at the LSM303DLH datasheet and had a d�j� vu ;-) It looks like ST has simply put a LIS331DLH and a HMC5843 into one package. (The HMC lacks the built-in voltage regulator) All data are nearly identical, even register and I�C addresses. Any information about that? I am currently using both (LIS... 18 Jan 2010 18:48

Oil sources Was: Re: Would magn. pole reversal actually messup electronic equipment?
Bill Miller wrote: "J Thomas" <jethomas5(a)gmail.com> wrote Bill Miller wrote: Here is a better link to the experiment itself: http://www.gasresources.net/AlkaneGenesis.htm http://www.gasresources.net/ Your other link gave a link to that. I'm not an expert in any of this. My own backg... 18 Jan 2010 16:33

Schematic preferences
Hi, Of course, this is *highly* subjective -- but, I'd enjoy hearing folks' "conventions" used when preparing schematics (that *others* will consume -- how you scribble for your own purposes isn't important as it depends a lot on what *you* want out of the drawing). I try to follow some general rules -- but a... 22 Jan 2010 18:36

Oil sources Was: Re: Would magn. pole reversal actually mess up electronic equipment?
"J Thomas" <jethomas5(a)gmail.com> wrote in message news:q6T4n.8153$nR4.1335(a)newsfe01.iad... Lots of <snips> Bill Miller wrote: In contrast, there seems to be a fair amount of theoretical and lab activity in taking carbonates (limestone, marble etc.) and subjecting them to intense heat and pressure ... 19 Jan 2010 04:40

Source for vintage hex LEDs?
Hi! Does anyone have a good source for HP5082-7340 (aka HDSP-0762) hex LED displays? I am working on a project that needs 10 of them and HP5082-7340's appear to be unobtainium and the HDSP-0762's are like $35 each. If anyone has any old stock, used ones, or pulls they would work. I'd prefer the HP5082-7340 di... 18 Jan 2010 22:09

Testing a Video Signal
We have just purchased a quantity of PCIe video cards with TV out (S-Video) and can only get a monochrome picture from the S-Video output. I have so far tried 6 different cards from 2 batches and all have the same fault. Here are my observations?: -Another brand of video card that used the same video chip (nV... 21 Jan 2010 13:28

Using a Ramdrive with LTSpice
I'm tried out a trial version of 'Ramdisk' and set aside 4G of memory (I have 8G) to be used as a ramdrive for the raw file created during an LTSPICE simulation.. Conclusion Yup. It's faster. Helps with long smps simulation. ... 20 Jan 2010 18:35

11-year old "engineer" needs counseling
http://www.signonsandiego.com/news/2010/jan/15/students-evacuated-school-chollas-view/ ... 28 Jan 2010 02:05