Warning: mysqli::__construct(): (HY000/1203): User howardkn already has more than 'max_user_connections' active connections in D:\Inetpub\vhosts\howardknight.net\al.howardknight.net\includes\artfuncs.php on line 21
Failed to connect to MySQL: (1203) User howardkn already has more than 'max_user_connections' active connectionsPath: ...!news.mixmin.net!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail From: Phil Hobbs Newsgroups: sci.electronics.design Subject: Re: more X-rays Silvertel PoE Supply Date: Thu, 3 Oct 2024 22:37:10 -0000 (UTC) Organization: A noiseless patient Spider Lines: 90 Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Injection-Date: Fri, 04 Oct 2024 00:37:11 +0200 (CEST) Injection-Info: dont-email.me; posting-host="b835f16d585e1d29b9d32dfa3a2d8110"; logging-data="4112190"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1/pkTIBsXvgOEV5q1nuD7yl" User-Agent: NewsTap/5.5 (iPhone/iPod Touch) Cancel-Lock: sha1:MdGDqo0o1WNdMLpkM6Ao9tBbo1U= sha1:lWv465VUSNFgz+b8Hm7rZbX5tSo= Bytes: 5020 john larkin wrote: > On Thu, 03 Oct 2024 06:38:41 GMT, Jan Panteltje > wrote: > >> On a sunny day (Wed, 02 Oct 2024 15:39:31 -0700) it happened john larkin >> wrote in : >> >>> On Wed, 2 Oct 2024 17:00:52 -0400, "Edward Rawde" >>> wrote: >>> >>>> "john larkin" wrote in message >>>> news:kqbrfjhrd5oto8ud8vm0395p6oo8eipige@4ax.com... >>>>> On Wed, 2 Oct 2024 11:46:21 -0400, "Edward Rawde" >>>>> wrote: >>>>> >>>>>> "john larkin" wrote in message >>>>>> news:v6mqfjd93ib6q8j7d7ontsaouidieh5b2u@4ax.com... >>>>>>> On Wed, 02 Oct 2024 06:22:43 GMT, Jan Panteltje >>>>>>> wrote: >>>>>>> >>>>>>>> On a sunny day (Tue, 01 Oct 2024 14:16:09 -0700) it happened john larkin >>>>>>>> wrote in : >>>>>>>> >>>>>>>>> >>>>>>>>> https://www.dropbox.com/scl/fo/s6wfz2xtdyd6tv32tq3fp/AET6J4oF84HG2hJMeST6F-E?rlkey=acyvuv4z0h2kg0x97azbed8uo&dl=0 >>>>>>>> >>>>>>>> Cannot make out much from those x-rays, pictures are better... >>>>>>>> you can probably see the traces just like that? >>>>>>> >>>>>>> The x-rays are fun, but are admittedly more useful for an opaque >>>>>>> potted module or an IC or discrete semi. I can prety well trace the >>>>>>> Silvertel without them. >>>>>>> >>>>>>> I have a gigantic scary Carribean guy who does the xrays and I wanted >>>>>>> an excuse for taking him to lunch, which turned into an interesting >>>>>>> hike around The Bernal Cut. He trashed the xray system software, and >>>>>>> had to rebuild it, and now it can do movies, which is great. >>>>>>> >>>>>>> I'd like to have some products that can be powered by PoE or a wart, >>>>>>> and may want to put two 24-volt PoE supplies in series to get 48, so I >>>>>>> need to understand how they work. The xrays just help a bit. >>>>>> >>>>>> If Ag9900 just works then why would you care how? >>>>> >>>>> Can I overpower it with a wart? Does that need another diode? >>>> >>>> Maybe. See other discussion in this thread. >>>> >>>>> >>>>> Can I run two 24v Silvertels in series to get 48? >>>> >>>> I don't see why not since the data sheet says isolated. >>>> It shouldn't be hard to verify that. >>> >>> Batteries are isolated, but a series string can destroy one cell by >>> back-biasing it. >>> >>> Some power supplies will latch up, or not start up, in series with >>> others. Lots of suplies won't start (and may fail) if their input is >>> pulled negative. >>> >>> As the number of items in a design increases, the probability of some >>> stupid error approaches unity. It's usually time efficient to be super >>> careful, as opposed to spinning a few PCB revs. >> >> Why always some XXXchip? >> What's wrong with designing with normal components and adding a known micro? > > That's exactly what I'm doing. Stock parts and an RP2040 CPU chip. > > There are *so many* Raspberry Pi kids out there! > > Now if I could build the hardware part of the product with Legos... > > > Over the past 30-odd years, various people have come up with the idea of using legos for optomechanics. Then they go away for a summer weekend and return to find that their gizmos are completely misaligned due to stress relaxation in the plastic. Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics