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John Robertson <spam@flippers.com>: Jan 27 09:51PM -0800 On 2019/01/26 8:36 p.m., Jeff Liebermann wrote: > <http://www.learnbydestroying.com/jeffl/crud/Paper-Slide-Rule-Calculators.jpg> > <http://www.learnbydestroying.com/jeffl/crud/Paper-Slide-Rule-Calculators-02.jpg> > Oddly, I don't seem to have one that does Ohm's Law.   There is the old PIRE wheel, or is that too simple for the OP?   Of course then you need to use either your head or a calculator - I mean really, I=E/R, how hard is that?   John :-#)#

"pfjw@aol.com" <peterwieck33@gmail.com>: Jan 28 05:37AM -0800 Web-based software is useful to calculate parallel resistors and such-like. There was a discussion in another group about how to hot-switch between two amplifiers, neither of which would like to be unloaded (but for different reasons).   Turned out that a parallel high-wattage resistor across the amp outputs would do the trick, after a bit of calculation. Using a web-based calculator greatly sped up the process.   http://www.1728.org/resistrs.htm     Peter Wieck Melrose Park, PA

Fox's Mercantile <jdangus@att.net>: Jan 28 07:44AM -0600 > Web-based software is useful to calculate parallel resistors > and such-like.   Yabut...Tubeguy wants something he can run on his PC since he has a shit connection to the web.   -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

"pfjw@aol.com" <peterwieck33@gmail.com>: Jan 28 06:05AM -0800 On Monday, January 28, 2019 at 8:45:04 AM UTC-5, Fox's Mercantile wrote: > Jeff-1.0 > WA6FWi > http:foxsmercantile.com   https://download.cnet.com/Ohm-s-Law-Free-for-Windows-10/3000-2121_4-77555568.html   That took less than a minute.   Peter Wieck Melrose Park, PA

Fox's Mercantile <jdangus@att.net>: Jan 28 08:19AM -0600 > https://download.cnet.com/Ohm-s-Law-Free-for-Windows-10/3000-2121_4-77555568.html   > That took less than a minute.   Thank you.     -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

adrian@poppyrecords.invalid.invalid (Adrian Tuddenham): Jan 28 02:43PM > Is there any Software to calculate Ohms Law and other electronics math?   Basic Ohm's Law calculations can be done on a pocket calculator without the need for anything more complicated. The biggest pitfall is knowing *which* voltage or *which* current is actually applied to a particular resistor, especially if there are several in some sort of array.; it is not always obvious.   The logic of real-life circuit problems is not particularly amenable to being sorted out by software.     -- ~ Adrian Tuddenham ~ (Remove the ".invalid"s and add ".co.uk" to reply) www.poppyrecords.co.uk

Rob_Lowe@hotmail.com: Jan 27 01:32PM -0500 I bought a house with a nice outdoor, flat stone tiled walk way. Unfortunately the tiler/installer was "quite sloppy" in a few areas. There many of the tiles now have a thin, but annoyingly Noticeble coating "film" of concrete grout on the top.   I have tried coarse steel wool, with limited (slow) improvement. Is there a better/ recommended way, to remove that concrete film? I would really like all tiles to be fully visible, no film.

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Jan 27 01:41PM -0500 > I have tried coarse steel wool, with limited (slow) improvement. Is > there a better/ recommended way, to remove that concrete film? I > would really like all tiles to be fully visible, no film.   Muriatic acid.   Cheers   Phil Hobbs

Michael Black <mblack@pubnix.net>: Jan 27 01:58PM -0500 > I have tried coarse steel wool, with limited (slow) improvement. Is > there a better/ recommended way, to remove that concrete film? I > would really like all tiles to be fully visible, no film.   This newsgroup is for the repair of electronic devices.   Surely you meant to post this to the repair newsgroup, I think alt.home.repair and just because that newsgroup has turned to mush is not a reason to post an off topic question here.   Michael

tabbypurr@gmail.com: Jan 27 02:49PM -0800 > I have tried coarse steel wool, with limited (slow) improvement. Is > there a better/ recommended way, to remove that concrete film? I > would really like all tiles to be fully visible, no film.   HCl is the usual solution. It does attack some stone. Sometimes you can just wet the grout for a while then scrub it off with a plastic scourer wad.     NT

Jeff Liebermann <jeffl@cruzio.com>: Jan 27 05:07PM -0800 >I have tried coarse steel wool, with limited (slow) improvement. Is >there a better/ recommended way, to remove that concrete film? I >would really like all tiles to be fully visible, no film.   As previously mentioned, use diluted muriatic acid. <https://www.google.com/search?q=cleaning+patio+muriatic+acid> I did that to my parents patios and walkways many years. It worked just fine but required some extra pre-cleaning and scrubbing to remove some soaked in grease and dirt where I had previously rebuilt an automobile engine. I don't recall exactly what cleaner I used except that it was made for the purpose and supplied by the local hardware store.   If your patio is made from flagstone, I suggest you apply a sealer after neutralizing the acid and letting it dry: <https://www.google.com/search?q=patio+flagstone+sealer> After acid cleaning, the surface becomes rather porous and will absorb and trap water, dirt, grease, mold, mildew, shoe scuff marks, etc. I suggest you avoid the "wet look" sealer as it's difficult to keep shiny.   This looks fairly accurate: <https://www.wikihow.com/Acid-Wash-Concrete>   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

"pfjw@aol.com" <peterwieck33@gmail.com>: Jan 28 06:02AM -0800 It is a process, and varies with where you live.   Muriatic Acid (follow package directions): https://www.tractorsupply.com/tsc/product/klean-strip-green-muriatic-acid-gallon-3441166?cm_mmc=Affiliates-_-Pepperjam-_-product-_-feed&utm_source=pepperjam&utm_medium=affiliate&utm_campaign=product-feed&affiliate_id=43737&click_id=2590323429&clickId=2590323429   And a stiff wire brush are your best options. Muriatic acid has a significant virtue, the active ingredient (hydrochloric acid) is volatile if not reacted, and forms salts with many compounds such that it is (relatively) environmentally benign as compared to many other options. It also attacks only the CEMENT portion of the grout, leaving the sand and stone untouched.   Other stuff:   If the walkway is subject to exposure (snow/rain) and you are in an area where there are freeze/thaw cycles, you need to be very careful in how you treat the surfaces when you are done cleaning. You may choose to seal the surface, and if you do so, be sure that it is fully dried (days, at least), and that you treat the stone and grout uniformly and with the same material. The sealant wants to be a clear, non-volatile material when cured, and absolutely not anything like Thompsons - which is absolutely worthless in any case.   https://rainguardpro.com/product/micro-seal/ is one of many Silane-based materials. Thoroseal is another. But Silane/Siloxane is the gold standard - assuming you have the gold.   So you understand the "why" of it: Most masons these days are poorly trained in how to mix mortars and grouts. Generally they make the mortar far to rich, so that it cures (NOT dries) far too hard. When that happens, water penetration into the stone pavers is greater than what it is to the grout. At which point, during the freeze-thaw cycles, the harder material (grout) will cause damage to the pavers _AND_ if that were not enough, tend to spall in thin layers. So, sealing everything properly will eliminate that problem.   In a warm climate, note that the harder of the two materials will generally fail ahead of the softer material due to thermal expansion and contraction. First it will separate by density, then the smaller sections will start to crack.   Best of luck with it!   Peter Wieck Melrose Park, PA

arlen holder <arlen@arlen.com>: Jan 28 01:59AM On Tue, 01 Jan 2019 14:44:32 -0800, Jeff Liebermann wrote:   > codec is somewhat negatated by the higher latency (delay) as compared > with G.711 (64Kbits/sec uncompressed). It takes time to compress the > audio, so watch out for echo problems.   Hi Jeff, Your suggestion has been working surprisingly well. Much appreciated the advice!   > I'm out of action for a while thanks to yet another kidney stone. Y're > on your own on this one.   Hope you feel better soon!   You're one of the few people on Usenet who are always purposefully helpful.

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Jan 27 03:35PM -0500 On 1/27/19 12:03 AM, Jeff Liebermann wrote: >> John :-#)#   > Nice idea. My initial guess(tm) was that the anti-reflective coating > on the camera lens would umm... not reflect anything:   It's the retroreflection from the surface of the image sensor that you see, like a cat's eye in the dark. If the sensor is at the focus of the lens, the reflection goes straight back to the light source.   Cheers   Phil Hobbs   -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510   http://electrooptical.net http://hobbs-eo.com

N_Cook <diverse@tcp.co.uk>: Jan 27 08:02PM Wanted to extend a small LCD display out of its little commercial box, by about 1m. Ribbon and ZIFs between the lcd pcb and main pcb was 0.5mm spacing. No profesional micro-soldering kit available, so poor-mans bodge/kludge. Some copper mesh from a craft shop, something to do with decorating birthday cards/scrapbook or jewellery or the like. Anyway uses 0.12mm diameter wire , woven into a mesh of 0.33mm spacing. Cut a length to span width of original ribbon and width enough to bridge and fan-out the gap to 0.05 inch ribbon or appropriate header, that eventually can be well anchored to the main pcb. Work under illuminated magnifyer or x10 USB microscope viewing. With good thin nose pliers remove filaments widthwise until about 6 filaments wide bit of mesh remains, enough to just hold the weft/warp? fibres in place, carefully disposing of those waste lengths of long wires. So protruding wires on each side. On one side fold back the ends of every other wire 3 times ,then leave extra 1 in place, and repeat along ,so every 3mm matches up 0.33 to the 0.5mm spacing. Tin all the ends of the wires. Liquid flux the lands at the ZIF socket. Temporarily clamp mesh to pcb and align the wires, using a needle. Find the finest of sewing needles, heat and push into a blank of hotmelt rod as a handle. Grind back the eye end until a tiny Y shape. Unclamp the mesh and continue removing the last 6 wires, careful about retaining all and disposing of these tiny bits of wire. For each soldering fill the Y with solder paste, and heat the Y area with soldering iron. Hopefully the bond between wire and land is better than to stainless steel. The de-deforming force of stripping the last 6 wires, is a good test of mechanical bond. Check continuity and isolation and slide some thin sleeving over each wire, perhaps lacquer in place. With wide spaced ribbon or whatever fixed to the pcb, solder the other end of the wires . Recheck continuity and isolation.

Jeff Liebermann <jeffl@cruzio.com>: Jan 27 09:57AM -0800 On Sun, 27 Jan 2019 08:16:49 -0800 (PST), Terry Schwartz   >On Saturday, January 26, 2019 at 10:24:27 PM UTC-6, Jeff Liebermann wrote: (...)   >Stop feeding the troll.   Is that an invitation to discuss the relative merits of the OP's trolling as compared to mine or yours? At least I have something to feed to the trolls. Surely, you must realize that anything which might be considered argumentative can also be considered trolling. Since I make it a point of only writing things that I consider worth reading, I find it difficult to distinguish between when I am trolling and when I'm merely providing entertainment for the readers. If I accede to your cease and desist demand, does that mean that I will then require your permission and editorial oversight before I am allowed to answer anyone's technical questions? If so, there are moderated newsgroups which would welcome your efforts.   Perhaps "Stop feeding the topic drifters" would be more useful and less attractive. Or better yet: "Thou shalt not post what thou also find unworthy of reading". <http://www.learnbydestroying.com/jeffl/crud/genesis.txt>     -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

Dipchanh@icloud.com: Jan 27 09:54AM -0800 Just joined in never too late. 1) check brushes ,blow out top of motor through Cover plate at the top turning motor with hand Sand brushes with light sand paper 2) If Magnet comes on then you have Power to circuit board. Unplug remove power. Remove 4 screws from cover plate where power cord comes in. Unplug black and white wires going to motor. Hook power directly to black and white wires. Motor will run if not there's a short on the top cord or the field cord is burnt. But then you would smell burnt wires. So check for short But before you do that the black and white wired you unplug from circuit board put you tester on AC voltage and hook up press green to start assuming power is on. MAKE YOUR CIRCUIT BOARD IS INSULATED (not touching metal) circuit board can short. when you press the green start you wound get 120 volts which means your circuit board is good if not getting any power there then board is bad. I don't do boards so I cant say. Board is around $125. Thanks for letting me post my 2 cent wort Please feel free to cal

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