On Sunday 31 January 2016 19:10:14 Dave Cole wrote: > On 1/31/2016 6:51 PM, John Kasunich wrote: > > On Sun, Jan 31, 2016, at 06:18 PM, Gene Heskett wrote: > >> On Sunday 31 January 2016 13:43:50 Jon Elson wrote: > >>> I can't imagine why you'd buy commodity semis from a Chinese > >>> source when there are great distributors like Digi-Key and > >>> Mouser, that are quite happy to serve small orders. > >> > >> Both of the above have minimum orders for me that are quite costly > >> for a 10 pak of anything in the transistor 10 cent to 5 dollar > >> price range. That and their sites search engines return what looks > >> to me to be random from dice throws results. If I go searching for > >> small hexfets I get 20,000 hits, none of which give me the data to > >> make a choice semi-intelligently. Digikey is slightly better, but > >> not enough to spend hours wading thru the selections while still > >> hiding the important data. More often than not, clicking on a fine > >> tune option, such as any case smaller than a to-220 returns zero > >> results and I know that there are smaller versions such as could > >> drive an ice cube relay at 12 or 24 volts. That can be easily put > >> in a to-92, or even in a SMD package, so why can't it be found? > > > > I find this rather confusing. Mouser is meh, but IMHO Digikey's > > search engine is simply outstanding. For example: > > > > I type MOSFET into the search box. It returns a list of categories. > > I pick "FETS - Single". It returns a list of 39000+ parts. > > I click the "In stock" box and "apply filters". List is now 17,999 > > parts. Scroll over to "Mounting Type", select "Thru hole" and apply > > filters. 3293 parts. Scroll over to "Supplier Device Package" and > > select the four TO-92 variants (ctrl-click for multiple selections). > > Apply filters, 123 parts. Under packaging, select "Bulk" and "Cut > > tape", (the other variants are for large quantities). Apply > > filters, down to 106. > > Select 40 to 100V in the drain-to-source voltage box, down to 59. > > Select all the sub-1-ohm ones in the Rds-on box, down to 7. > > Put "1" in the desired quantity box. Hit the up arrow in the price > > column to sort cheapest first (giving a quantity moves anything with > > a minimum order larger than that quantity items to the bottom of the > > list). Cheapest part is at the top of the list, MicroChip > > TN0604N3-G. Click on the PDF icon in the 2nd column and I'm looking > > at a data sheet. Click on the links in the 4th or 5th column and I'm > > looking at the details page for that part. Add 1 to cart. Place > > order. There is no minimum total order (although it sucks to spend > > $6 on shipping when you are ordering a $1 part). > > > > It took me less time to find that part than it took to type out what > > I did. > > > > Digikey is absolutely my first stop for just about any part, both > > for hobby stuff and for my day job. Like McMaster, their prices may > > be a bit higher than some other sources, but usually not enough to > > matter, and the search engine more than makes up for it. > > > > John Kasunich > > > > John Kasunich > > jmkasun...@fastmail.fm > > The other nice thing about Digikey is that they will ship a small > order via First Class mail (at least they used to do that..) > > I've ordered a dozen chips for some project and the total has been > something like $9.00 plus $1.30 for postage and the parts show up two > days later in a first class envelope. > > Whats not to like about that! > > Dave > Nothing. But I usually bought IC's by the tube and that doesn't fit in a postal envelope. There were times when after a lightning hit on the STL tower, I'd need 2 sticks of tlo-84's to get all the audio working again.
I always said to myself that I'd add some snubber diodes, downstream of about half of the buildout resistors to keep the EMP from going above or below the power rails, but that would have required a fresh PCB design to find room for 16 more resistors and 16 more diodes per board. My fault but I never managed to find both the time and the round tuit in the same 2 weeks. And of course the NIH syndrome, as the design was 100% mine in the first place. Fidelity wise, it was one hell of an improvement over ANYTHING I could buy for a thou$and a 4 output card & these were 2 stereo channels with 4 outputs each on each card. Crowded, 22 such cards in a 19" rack cage. No slew rate limits in sight, it could make 30v p-p at 30 kilohertz. Some cross-over distortion started creeping in at about 25 kilohertz and above 27 volts p-p, but no huan ears can hear that. At normal signal levels, the distortion was in the sub .01% scale. But it could not take the EMP from a nearby lightning hit when some of the I/O cables were 200 feet long. Big building, was going to be a Buick dealership but he ran out of money before he opened. Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> ------------------------------------------------------------------------------ Site24x7 APM Insight: Get Deep Visibility into Application Performance APM + Mobile APM + RUM: Monitor 3 App instances at just $35/Month Monitor end-to-end web transactions and take corrective actions now Troubleshoot faster and improve end-user experience. Signup Now! http://pubads.g.doubleclick.net/gampad/clk?id=267308311&iu=/4140 _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
