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Stijn De Jong <stijndekonlng@nlnet.nl>: Mar 19 06:08PM -0800 SUMMARY: What service is it that does the Wi-Fi scanning on Android anyway? http://i.cubeupload.com/lYvIsQ.jpg   DETAILS: You probably don't know the answer but what allows WiFi scanning anyway?   In the past few weeks I changed so many things on my Android 4.3 phone that I don't remember what killed WiFi scanning but I just want to ask, in case someone knows, what actually does the WiFi scanning on an Android phone?   For example, I have over a half dozen access points at home, all being broadcast in the clear, WPA2/PSK-AES protected, which the third part programs find with no problem (e.g., Fritz! WLAN, WiFi Manager, WiFi Connection, WiFi Analyzer, InSSIDer, WiFi Analysis, WigLe WiFi, etc.). http://i.cubeupload.com/fV8D4d.jpg   Some (but not all) of the 3rd-party apps can find all the networks, yet, the scan button in Android 4.3 doesn't find a single network anymore. What on Android does the scanning anyway? http://i.cubeupload.com/TNGRGg.jpg   I can certainly manually press the default Android 4.3 "Add Wi-Fi network" and then it will connect to any network I manually type in, but it won't *find* a network on its own anymore, even though the signal strength is clearly in the negative forties, fifties, sixties, and seventies (i.e., the signal strength is just fine). http://i.cubeupload.com/lYvIsQ.jpg   I realize probably nobody knows the answer but just in case you do, what service on Android does the WiFi access-point scanning anyway?

Jeff Liebermann <jeffl@cruzio.com>: Mar 19 08:26PM -0700 On Sun, 19 Mar 2017 18:08:33 -0800, Stijn De Jong   >what allows WiFi scanning anyway?   Wrong question. What you should be asking is what disables wi-fi scanning. That's easy, 2 ways. 1. If your phone is setup to act as a hot spot so that others can borrow your cellular data bandwidth, it will kill scanning. That's because a hot spot requires that the channel number be fixed and not a moving target. 2. If your phone is in peer to peer mode instead of infrastructure. There are many reasons for this to happen. For example, printing directly to an HP ePrint printer or Apple Airprint printer. I think (not sure) that a GoPro camera connection does the same thing.   Note that the phone cannot be in infrastructure (what you want) and peer-to-peer mode (what you don't want) at the same time.   >I realize probably nobody knows the answer but just in case you do, what >service on Android does the WiFi access-point scanning anyway?   I'll take the easy way out and claim ignorance.   -- 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

Stijn De Jong <stijndekonlng@nlnet.nl>: Mar 19 07:53PM -0800 On Sun, 19 Mar 2017 20:26:25 -0700, Jeff Liebermann wrote:   > (not sure) that a GoPro camera connection does the same thing.   > Note that the phone cannot be in infrastructure (what you want) and > peer-to-peer mode (what you don't want) at the same time.   Those are both good answers as to what disables wifi scanning.   The phone has never been set up as a hotspot since the last factory reset, although it certainly would be possible to set it up as a hotspot since it's T-Mobile which allows that on all their phones. But it's not currently set up as a hotspot to my knowledge. But that's an interesting observation.   I'm not sure what "peer-to-peer mode" is for Android.   Googling https://www.google.com/search?q=android+peer-to-peer+mode   I found this: https://developer.android.com/guide/topics/connectivity/wifip2p.html Which says that two Android devices can connect in peer-to-peer mode (aka WiFi Direct).   I have never used WiFi Direct so I don't think it's in peer-to-peer mode. Besides, the phone connects to WiFi when I manually type in the (very long complex) SSID.   It just won't find any SSID when I press the scan button. I think it's time for a factory reset, which should fix the problem.

"pfjw@aol.com" <pfjw@aol.com>: Mar 20 04:20AM -0700 On Sunday, March 19, 2017 at 10:07:59 PM UTC-4, Stijn De Jong wrote: > http://i.cubeupload.com/lYvIsQ.jpg   > I realize probably nobody knows the answer but just in case you do, what > service on Android does the WiFi access-point scanning anyway?   The Troll is back. Please don't feed the troll.

jurb6006@gmail.com: Mar 20 04:42AM -0700 >"The Troll is back. Please don't feed the troll. "   I don't see any trolling here, I see a perfectly valid question. I don't have any answers for the OP but I read the thread to maybe learn something.   Just what is it that indicates a "troll" to you ? The fact that he said maybe nobody has an answer ? Or is it the Oriental sounding name ? What is a troll ?   And BTW, I noticed YOU responding to this thread, isn't that feeding the troll ?   I don't mind an antagonist, this is Usenet and if that bothered me I would not be here. But I just have questions.

"pfjw@aol.com" <pfjw@aol.com>: Mar 20 05:00AM -0700 a) The OP changes his handle about as often as the typical individual changes his socks. b) His handles are typically a close analogy to some moderately famous person - mostly military individuals. c) His trolls are typically wild hair questions on obscure and meaningless points of negligible utility. "How many angels can dance on the head of a pin?" is a deeply meaningful discussion by comparison. d) When he sets the hook, his threads can go on..... and on.... and on, with no meaningful results.   So, my 'response' is to suggest *not* rising to the bait.

"Carlos E. R." <robin_listas@es.invalid>: Mar 20 02:53PM +0100 On 2017-03-20 04:53, Stijn De Jong wrote:   > complex) SSID. > It just won't find any SSID when I press the scan button. > I think it's time for a factory reset, which should fix the problem.   My phone finds all SSIDs, but connects to none. If I tap on the home ssid, it asks for the password (which it knows for sure).   Instead, I tap "more options", which displays the same list of SSIDs in white background instead of black. There I switch off the WiFi, than on again, and it instantly connects to my WiFi remembering its password.   This behaviour started about last November or December.   I also noticed that Bluetooth would not automatically connect to my car hands-free device. It has started working again after I received a security update about a week ago.   -- Cheers, Carlos E.R.

mike <ham789@netzero.net>: Mar 20 09:07AM -0700 > c) His trolls are typically wild hair questions on obscure and meaningless points of negligible utility. "How many angels can dance on the head of a pin?" is a deeply meaningful discussion by comparison. > d) When he sets the hook, his threads can go on..... and on.... and on, with no meaningful results.   > So, my 'response' is to suggest *not* rising to the bait.   Perhaps YOU could resist responding and allow others the same decision.

Phil Allison <pallison49@gmail.com>: Mar 19 05:58PM -0700 > > >> find a substitute.   > I would try a MJE350(pnp/300V/500ma/20w/TO-126/hFE=30-240). > Anchor Electronics http://anchor-electronics.com/ wants US$0.95 each.     ** I have already pointed out that Sydney's biggest spare parts dealer( WES components) has the BF470 in stock for under $1.   Sylvia lives in Sydney.     .... Phil

Phil Allison <pallison49@gmail.com>: Mar 19 06:55PM -0700 Phil Allison wrote:   > ** I have already pointed out that Sydney's biggest spare parts > dealer( WES Components) has the BF470 in stock for under $1.   ** They have the BF472 as well, same price   Sylvia lives in Sydney.         ..... Phil

"jfeng@my-deja.com" <jfeng@my-deja.com>: Mar 20 08:28AM -0700 On Sunday, March 19, 2017 at 6:56:07 PM UTC-7, Phil Allison wrote: > Sylvia lives in Sydney. > ..... Phil That was not obvious to me from the posting in sci.electronics.repair. Where was this information to be found in that posting? And if Sylvia is in British Columbia, Anchor Electronics is a plausible supplier.

legg <legg@nospam.magma.ca>: Mar 19 07:32PM -0400 Looking at Low-Frequency noise on a 60Hz power supply, using a Rigol DS1054 and not getting very far.   One puzzling issue is, when ch3 or ch4 scope probe grounds are connected to a common 0V reference point, a low frequency common mode signal shows up in the shorted probe of CH1 or Ch2, when connected to the same 0V reference. Disconnecting CH3/CH4 ground clips removes the signal in shorted CH1/CH2.   Measurement using a current probe show >20mAppk of LF current passing in the CH1 or CH2 probe lead, generating a >20mvppk voltage on the display for that particular channel, but only when CH3 or CH4 ground leads are connected.   The scope probes are those supplied with the retail unit.   It's perfectly possible that the DUT being tested has ground leakage issues, but the safety ground lead on both DUT and scope are secure and share a common return point. The 0V reference in the DUT has a parallel RC connection to the frame, so a small scope probe ground current could be anticipated.   The 0V reference effect is only present when the largish 60Hz power unit is on. The shape of the voltages and currents look ~capacitive, with displacement coincident with line zero-crossing, where most low-frequency noise in the DC regulator outputs is anticipated, and so cannot be isolated or ignored.   Is there some issue with DS1054 ground impedance imbalance between channels that can be corrected?   Is there some issue with basic LF CMRR of the DS1054 inputs that needs looking into?   I have other scopes to use for this work, but expected the DS1054 to be useful in simple low frequency measurement.   RL

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Mar 20 11:50AM +1100 On 20/03/2017 10:32 AM, legg wrote:   > I have other scopes to use for this work, but expected the DS1054 to > be useful in simple low frequency measurement.   > RL   **I can't speak for that precise problem with the 1054Z, but I can say that the supplied probes are, arguably, the worst probes I have ever encountered. I used mine for about a month, before I threw them out and replaced them with decent probes. Perhaps you should start there. They really are horrible probes. It's weird, because the probes supplied with my earlier, 1052, were not as bad. Not Tek quality, but passable.   -- Trevor Wilson www.rageaudio.com.au

Phil Allison <pallison49@gmail.com>: Mar 19 06:07PM -0700 legg wrote:   > display for that particular channel, but only when CH3 or CH4 ground > leads are connected.   > The scope probes are those supplied with the retail unit.   ** Sounds like the probe leads are forming a loop and a nearby transformer is injecting AC frequency into it. What happens if you twist all the leads together, closing up the loop area to almost nothing?     .... Phil

legg <legg@nospam.magma.ca>: Mar 19 10:32PM -0400 On Sun, 19 Mar 2017 19:32:30 -0400, legg <legg@nospam.magma.ca> wrote:   The scope probe pairs are normally used as bundled pairs to cut down on desktop clutter.   It appears that the current is being induced in the physical loop, created by the separation of the bundled pairs, by a strong local magnetic flux field being generated by the DUT power supply.   The power supply employes two large low frequency ferroresonant power transformers inside a skeleton frame.   The current amplitude can be modulated/inverted by manipulation of the loop's area and orientation.   Methods of reducing these effects (the transformers stay) in measurement and basic circuit function are being examined.   RL

Phil Allison <pallison49@gmail.com>: Mar 19 08:00PM -0700 legg wrote:   > loop's area and orientation.   > Methods of reducing these effects (the transformers stay) in > measurement and basic circuit function are being examined.   ** Say "thankyou Phil" for spotting this so quickly from the other side of the planet.   And despite a convolted and misleading description.       ..... Phil

legg <legg@nospam.magma.ca>: Mar 19 11:53PM -0400 On Sun, 19 Mar 2017 20:00:52 -0700 (PDT), Phil Allison   >And despite a convolted and misleading description.   >..... Phil   Sorry Phil, it's only a fluke that I copied this to sci.electronics.repair in the first place, after little response on S.E.D. I did see Trevor's note.   Only placed the last note here for consistency.   The bundled pairs of scope probes were originally adopted as standard practice in order to avoid this issue, so long ago that I was unprepared to consider the effect in scopes with a larger channel count.   Sensing and power lead wiring in or around that beast is already in twisted pairs for similar reasons, but I'm going to have to re-examine the voltage vs current pair issue and a number of rotary switch routings for the same, if reduced, influence.   Thanks for your input.   RL

Andy Burns <usenet@andyburns.uk>: Mar 20 08:56AM legg wrote:   > Is there some issue with DS1054 ground impedance imbalance between > channels that can be corrected?   I thought they were all commoned via the chassis? I usually only connect the ground clip of a single probe.

legg <legg@nospam.magma.ca>: Mar 20 09:02AM -0400 On Mon, 20 Mar 2017 08:56:41 +0000, Andy Burns <usenet@andyburns.uk> wrote:   >> channels that can be corrected?   >I thought they were all commoned via the chassis? >I usually only connect the ground clip of a single probe.   Read on.....   RL

jurb6006@gmail.com: Mar 19 01:21PM -0700 If the switch is mechanical there is a way to wire it to be always on. Just do that, and just leave it on.   I know you can't do that with tubes or class A stuff, but a regular class AB amp will be fine. And usually it will sound better and better as it burns in. Just leave it on forever. I do with mine, and I do not see a huge electric bill or anything. They might pull about three clock radios worth of power, which is about nothing. I mean like a dollar a month if that.

ohger1s@gmail.com: Mar 19 01:54PM -0700 > If the switch is mechanical there is a way to wire it to be always on. Just do that, and just leave it on.   Hmmm.. functional but no charm... Here's what he needs:   http://www.antiquesnavigator.com/d-31159/large-antique-electric-chair-knife-switch-slate-copper.html   Four sheet metal screws and some hookup wire and he's back in business. Plus, he gets the added benefit of saying "muwahahahaha" every time he turns it on..

"Benderthe.evilrobot" <Benderthe.evilrobot@virginmedia.com>: Mar 19 06:42PM "Michael A. Terrell" <mike.terrell@earthlink.net> wrote in message news:mbidndeCK4xDv1PFnZ2dnUU7-XednZ2d@earthlink.com...   >> Thanks.   > I use Revo Uninstaller:   > <http://www.revouninstaller.com/revo_uninstaller_pro_lpggl_nc_downloads.html>   Thanks - but it didn't show me anything that needed removing.

"David Farber" <farberbear.unspam@aol.com>: Mar 19 11:00AM -0700 Bruce Esquibel wrote: > boards are similar.   > -bruce > bje@ripco.com   Hi Bruce,   As far as I can tell, the components in question are not custom. IC 503 is a standard dual op-amp whose DC output voltages start creeping up until it reaches Vc or 12 volts and then the positive half of the signal is clipped.   The board in question is ENC-093 version C. It's a plug-in board as many of the circuit boards are.   Thanks for your reply. --   David Farber Los Osos, CA

bitrex <bitrex@de.lete.earthlink.net>: Mar 19 01:20PM -0400 On 03/18/2017 09:30 PM, Jeff Liebermann wrote: > and features that no longer work correctly. Those are rare and can be > handled by with various BIOS recovery tricks. I had some bios > failures maybe 10 or more years ago, but not since. Do it.   Thanks much for the advice, I'll give one of the eBay clone chargers a try!

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