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Halloween_Spooook@fear.com: Oct 31 09:11AM -0600 I just found a human skeleton in a radio. All that remains are bones and a cap that says "RCA TUBES". In the bony right hand is clutched a wirecutter with severely melted blades. It appears this man was electrocuted and died inside this old tube radio, from the 1950's.   Apparently he was repairing the radio and was electrocuted and sucked inside the radio by the high voltage. From the looks of things, this body has been inside this radio for 40 or 50 years.   I need to replace one of the tubes, but that tube is inside the skull. How do I get to that tube?   I also need to replace the speaker because one of his feet penetrated the cone while he was dying. The bones from that foot are wedged between the spider, and the voice coil is melted around the ankle bone. I dont want to disturb the skeleton, so how do I change the speaker?

Klay Anderson <klay@klay.com>: Oct 30 10:11AM -0700 On Thursday, October 26, 2017 at 9:34:57 AM UTC-6, rickman wrote: > > I need to put a momentary on switch in my dashboard, and the one I > > bought doesn't have a hex nut for the top nut but a round serrated ring > > to hold the switch in place.   The old-timers way is to tighten the hex nut on the rear of the switch shaft once you have the knurled nut flush with the panel. There are angled wrenches just for this. I've a few but (as an old-timer) I don't remember where I bought them. Seems to me they were a part from a switch or pot manufacturer.

Bob Engelhardt <BobEngelhardt@comcast.net>: Oct 30 07:01PM -0400 On 10/27/2017 1:26 AM, mike wrote:   > ... The person who buys it at your estate sale might be surprised > when he accidentally pops the top at highway speed.   A big problem in today's consumer market is the effort manufactures put into idiot-proofing stuff. Let the damn idiots do it & fuck 'em.

bruce2bowser@gmail.com: Oct 30 08:20PM -0700 >> little [bit of a scratch], but memory plays tricks on mpeople. And it didn't tear the   >> cloth but it still scratched, and that surprised me.   >That's why they make strap wrenches.   For cars, a leather belt helps in changing the oil filter, and this material is also more sturdy than cloth. It would have to be cut in a very narrow strip, though.

Jeff Liebermann <jeffl@cruzio.com>: Oct 30 07:28PM -0700 On Sun, 29 Oct 2017 21:35:35 +0000 (UTC), harry newton >neighbor is only a few hundred feet away line of sight.   >So I'm overdriving the radio by accident, I think. >I thought they throttled themselves so that they'd never exceed the limit.   I deduce by reading between your lines that you have an unspecified model 2.4Ghz radio and that you're using it in point-to-multipoint topology. Therefore, you're limited to 4 watts EIRP which translates into +26dBm into an 18dBi dish.   >it must be defaulting to the legal limit for point to point even though >it's set up as an access point hanging off a wired router acting as a >repeater.   As far as I know, there's no connection between the transmit power and the mode of operation. Since the radio has no way to know what gain antenna is attached, it has no way to determine if the radio is used in accordance with 15.247. Setting up your Ubiquiti for bridging, which is what's normally used for point to point, should not have any effect on the transmit power.   Note that if this were a cellular system, which has ATC (automagic transmitter control), the SNR (signal to noise radio) from the receiver at the other end of the link would be reported back to the transmit radio and adjusted for the minimum RF level necessary to maintain a decent BER (bit error rate) or PER (packet error rate). However, wi-fi is not cellular, so forget about doing it the way you've been guessing that it works.   >> ambiguous. Did you reset the router after installing the firmware >> update?   >The radio rebooted itself after the firmware update.   Reboot is NOT the same as reset to defaults. When you reboot, all it does is unload the current setting from working memory, and reload the saved settings from NVRAM into working memory. When you update the firmware, there's no guarantee the setting saved in NVRAM are going to work correctly.   >whatever defaulted after I set it.   >So I didn't touch the antenna setting. >Nor did I touch transmit power.   Let me make this really simple. If you're radio is going goofy things after a firmware update, punch the reset button and put everything back to the factory defaults. Then, configure it to your favorite working numbers and see if the problem goes away.   >So it *defaulted* to the 44 Watts, which, for a home radio, is overkill >unless I'm going 10 miles but it's not even half a mile that I'm going.   Everything you do seems to be overkill.   >So I'll dial down the transmit power.   Dial, as in a knob and potentiometer? How quaint.   >> Busy patching the roof today before the sky falls on me tonite.   >Good luck with the roof!   I think I have all the potential leaks plugged. Of course, I've been saying the same thing for last 15 years or so.     -- 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

Chuck <ch@dejanews.net>: Oct 30 02:03PM -0500 >Any known drift component in those amps over 30 years? >Plenty of yellow peril, now dark brown, milk-glue but tuner working , >where marginal conductivity would show up. A power supply electrolytic cap along with the brown glue can cause this problem. It should have high ESR. Haven't repaired one in the last 18 years so I can't give you the cap no..   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

Chuck <ch@dejanews.net>: Oct 30 01:56PM -0500 On Mon, 30 Oct 2017 09:15:33 -0700 (PDT), John-Del <ohger1s@gmail.com> wrote:     >> -- >> tb   >Then what you need is a learning remote. They used to be popular - don't know if they still make them. Google "learning remote".   Signature 2000s were made by different companies. The one you have was probably one made in Taiwan by an unknown television manufacturer. (I.E. Not Fulet, AOC or Sampo.) I would try NEC codes because some of these off brand sets used NEC ics.   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

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oldschool@tubes.com: Oct 29 03:01PM -0600 On Sun, 29 Oct 2017 13:24:24 +0000 (UTC), Bruce Esquibel <bje@ripco.com> wrote:   >I'll give ya a +1 for both of these, in 1990 remote control sets were not >entirely standard issue, especially on the lower end (which MW falls into) >and trying all 999 codes might be the only way.   I once tried all 999 codes on a Universal remote. NONE of them worked. I just wasted a lot of my time doing it. Some, if not most of them are not as "universal" as they claim to be.

John-Del <ohger1s@gmail.com>: Oct 29 04:11PM -0700 On Sunday, October 29, 2017 at 12:16:48 PM UTC-4, Allodoxaphobia wrote: > > and trying all 999 codes might be the only way.   > No one has yet mentioned the ultrasonic or RF remote controls....   > Jonesy     If there was an audio or rf remote used in a 1990 domestic TV, I'm unaware of them, and I repaired just about every TV that was ever sold in this country. TVs went IR in the late 70s - an RCA B&W remote portable being the last "impac" tuning fork clicker that I'm aware of (mechanical tuner with AC motor drive).

Sjouke Burry <burrynulnulfour@ppllaanneett.nnll>: Oct 30 12:30AM +0100 On 30-10-2017 0:11, John-Del wrote:   >> No one has yet mentioned the ultrasonic or RF remote controls....   >> Jonesy   > If there was an audio or rf remote used in a 1990 domestic TV, I'm unaware of them, and I repaired just about every TV that was ever sold in this country. TVs went IR in the late 70s - an RCA B&W remote portable being the last "impac" tuning fork clicker that I'm aware of (mechanical tuner with AC motor drive).   A tv repair guy told me about a mystery repair, where they were called in several times for a tv which was switching channels all the time. remote control was using sound. He finally found the reason for the errors. He saw a parrot opening its beak, each time the tv switched. The stupid bird imitated the sonic when he disliked the tv program.... Cure? Remove the bird.....

Mike Coon <gravity@mjcoon.plus.com>: Oct 30 10:33AM In article <59f66444$0$1714$e4fe514c@textnews.kpn.nl>, burrynulnulfour@ppllaanneett.nnll says...   > He saw a parrot opening its beak, each time the tv switched. > The stupid bird imitated the sonic when he disliked the tv program.... > Cure? Remove the bird.....   No, promote the bird to "genius"! Replace TV.   Mike.

John-Del <ohger1s@gmail.com>: Oct 30 06:43AM -0700 On Sunday, October 29, 2017 at 7:30:58 PM UTC-4, Sjouke Burry wrote: > He saw a parrot opening its beak, each time the tv switched. > The stupid bird imitated the sonic when he disliked the tv program.... > Cure? Remove the bird.....   You just triggered a long dormant memory. One of the tricks techs would do on the early ultrasonic remote receivers was to jingle their keys right at the TV's microphone. If the TV responded in any way, we'd just order a new transmitter. Of course, the old "impac" tuning fork "clickers" never quit entirely.   Young guys could put the transmitter right against their ear and hear them work. Whether they were fundamental or harmonics they were hearing I don't know.

"tb" <nospam@example.invalid>: Oct 30 02:57PM On 10/29/2017 at 8:56:01 AM Roger Blake wrote:     > As others have pointed out it is quite possible that set did not come > with a remote control. Is there a visible infrared receiver on the > front?   Yes, there is an infrared receiver on the front of the TV set. And the TV came with its own remote control which still works.   I was just hoping to use a single remote control for TV and converter box, instead of two...   -- tb

John-Del <ohger1s@gmail.com>: Oct 30 09:15AM -0700 On Monday, October 30, 2017 at 10:57:54 AM UTC-4, tb wrote: > box, instead of two...   > -- > tb     Then what you need is a learning remote. They used to be popular - don't know if they still make them. Google "learning remote".

whit3rd <whit3rd@gmail.com>: Oct 29 11:23PM -0700 > Freeze spray is still with us. It is useful for tracing intermittents and components that fail when warmed up. But, be very careful with it. Cold spray hitting an overheated part or board can cause fractures - which can cause trace failure.   But, it has other uses. A little freeze spray onto one of dozens of DC/DC converters identified the source of an annoying crosstalk situation, and we gained about 6 dB of extra signal/noise, once I'd isolated the ripple source. You can also (roughly) identify hot components, by observing how fast the frost dissipates.

tabbypurr@gmail.com: Oct 30 04:56AM -0700 On Monday, 30 October 2017 06:23:14 UTC, whit3rd wrote: > identified the source of an annoying crosstalk situation, and we gained about 6 dB of > extra signal/noise, once I'd isolated the ripple source. You can also (roughly) identify hot > components, by observing how fast the frost dissipates.   I suspect an IR thermometer is about the same price as a can of freeze spray nowadays.     NT

"pfjw@aol.com" <pfjw@aol.com>: Oct 30 05:18AM -0700 > I suspect an IR thermometer is about the same price as a can of freeze spray nowadays.   About. But, here is the biggest issue with these devices. I have a reasonably good one, with a reasonably fine pitch. The target diameter at 12" is 1.5". For those using the new currency: 38mm at 300mm. For an idea of target-creep, 3" at 36", 75mm at 900mm, and so forth.   Which must be kept in mind when in use. The little laser light is merely a visual guide, not the size of the target.   Peter Wieck Melrose Park, PA

Tim R <timothy42b@aol.com>: Oct 30 05:19AM -0700 We have a FLIR camera at work.   It was $3500 when we bought it but well worth it for diagnosing hot components.   I see they're only $5-600 on Amazon now. There's even an iPhone version for $200.

Jeff Liebermann <jeffl@cruzio.com>: Oct 29 12:41PM -0700 On Sun, 29 Oct 2017 16:42:22 +0000 (UTC), harry newton >the radio says transmit power is 26dBm into a built-in 18dBi dish antenna, >so the EIRP of the stock unit set for the USA would be too high at >26+18=44dBm in the USA.   Are you doing point to multipoint or point to point?   <https://www.air802.com/fcc-rules-and-regulations.html>   5GHz is different quite different. Might be helpful if you describe what you're using for hardware, what band you're using, and your wireless network topology.   >whatever the USA legal limit is); but why would AirOS report bogus number >then?   >What are those decibel numbers in AirOS actually *telling* me?   One of the dangers of updating firmware is that the saved or stored values might not work with the new firmware if they've shifted memory location between versions. This is almost guaranteed for major revision changes in firmware. Less so for minor changes. When in doubt, print your your settings, reset the router, and manually setup the numbers. Krack firemare tweeks seem to be a rush job and fall in the category of "customer tested software".   You mention that "it's all set to the defaults" which is rather ambiguous. Did you reset the router after installing the firmware update?   Busy patching the roof today before the sky falls on me tonite. -- 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

harry newton <harry@is.invalid>: Oct 29 09:35PM He who is Jeff Liebermann said on Sun, 29 Oct 2017 12:41:28 -0700:   > Are you doing point to multipoint or point to point? > <https://www.air802.com/fcc-rules-and-regulations.html>   Thanks Jeff.   Given the 2.4 GHz antenna dish is 18 dBi, the chart says the max is a. Point to multipoint (18dBm or 63mW transmit) into (18dBi antenna) = (36 decibels or 4 watts)   b. Point to point (26dBm or 400mW transmit) into (18dBi antenna) = (44 decibels or 25 watts)   The radio is set up as an access point, exactly how you suggested Rod Speed set up his antenna outside his house to feed his neighbor Wi-Fi where his neighbor is only a few hundred feet away line of sight.   So I'm overdriving the radio by accident, I think. I thought they throttled themselves so that they'd never exceed the limit.   > 5GHz is different quite different. Might be helpful if you describe > what you're using for hardware, what band you're using, and your > wireless network topology.   I have plenty of 5GHz Ubiquiti equipment (Rocket M5, for example, with a 30dBM dish), but this particular radio is one of my smaller ones, which is the Ubiquiti PowerBeam M2 400, which is only 26 decibels of transmit into an 18dBi antenna.   But even so, it has no problem getting to the legal limit it seems, where it must be defaulting to the legal limit for point to point even though it's set up as an access point hanging off a wired router acting as a repeater.   It only has to paint the barn with 2.4GHz WiFi to feed the cameras which are about a half kilometer away, which is nothing for this type of WiFi radio.   > You mention that "it's all set to the defaults" which is rather > ambiguous. Did you reset the router after installing the firmware > update?   The radio rebooted itself after the firmware update.   What I mean by defaults is the radio is set up to be an access point at a certain IP address in bridge mode, but that's all I set. The rest is whatever defaulted after I set it.   So I didn't touch the antenna setting. Nor did I touch transmit power.   So it *defaulted* to the 44 Watts, which, for a home radio, is overkill unless I'm going 10 miles but it's not even half a mile that I'm going.   So I'll dial down the transmit power. Thanks.   NOTE: For those reading this, if you need an access point to paint an area between hundreds of feet and a couple of miles away with 2.4GHz or 5GHz WiFi signal, you can get Ubiquiti or Mikrotik radios for about the same price as you paid for your last home router - but which are so much more powerful (aka directional) than a radio with an omni, that it isn't funny.   > Busy patching the roof today before the sky falls on me tonite.   Good luck with the roof!   Our power went out again yesterday (it goes out once a month) and we didn't even have much wind coming up from your side of the ocean.

Jeff Liebermann <jeffl@cruzio.com>: Oct 29 01:16PM -0700 On Wed, 25 Oct 2017 21:15:52 -0400, micky <NONONOmisc07@bigfoot.com> wrote:   >I need to put a momentary on switch in my dashboard, and the one I >bought doesn't have a hex nut for the top nut but a round serrated ring >to hold the switch in place.   I use these: <https://www.harborfreight.com/3-piece-long-reach-hose-grip-pliers-37909.html> $15 for 3 pliers. They're made for removing automotive hoses, vacuum lines, fuel lines, etc. You can't tell from the photo, but the insides of the cricular area is serrated for a better grip, which should mate somewhat with your switch nut. The 45 degree tip angle is also handy for clearing other junk on a front panel.   More: <https://www.google.com/search?q=hose+grip+pliers&tbm=isch>   -- 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

Andy Burns <usenet@andyburns.uk>: Oct 29 04:53PM harry newton wrote:   > I think what you're saying is that if they can get to *any* of your > devices, over the Internet, then, *from those devices*, they can intercept > your traffic to, for example, your Linux laptop or Android smart phone.   I think in your case you say your house is out of wifi range of your neighbours; but since you're advising friends and family, it could be that one house's fridge/camera/thermostat hacks the neighbour's wifi traffic ...

harry newton <harry@is.invalid>: Oct 29 05:29PM He who is Andy Burns said on Sun, 29 Oct 2017 16:53:03 +0000:   > neighbours; but since you're advising friends and family, it could be > that one house's fridge/camera/thermostat hacks the neighbour's wifi > traffic ...   I understand only the *basics* of that argument, which is that if you have device 0 (the router), and then client 1 (refrigerator) and client 2 (Android phone), and client 3 (linux laptop) that *all* are vulnerable.   The basic argument is that if someone gets in on client 1, 2, or 3, then the *whole* network is compromised.   But is it?   If client 1 is a refrigerator with very poor security, I get it that they can hack easily into client 1.   All I'm asking is how does access to client 1 give them access to router 0 which "controls" the entire LAN?

William Unruh <unruh@invalid.ca>: Oct 29 06:21PM > can hack easily into client 1.   > All I'm asking is how does access to client 1 give them access to router 0 > which "controls" the entire LAN?   It doesn't directly. But they now have control of a wireless card, which they can adapt (software) to listen in on the traffic between your computer and the router (remember that the wireless signal goes everywhere), and can then subvert the communication between the computer and the router forcing the system into negotiation replay. I have no desire to figure out exactly how to do that, just that with fridges etc around with zero security, they have an in to your local network, and quite possibly can use that to run a Krack on the computer and the router.

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harry newton <harry@is.invalid>: Oct 29 04:42PM How many decibels does the router/radio below really output? ('cuz 26 + 18 is too high)   In the before-and-after krack-update screenshot below, I'm confused because the radio says transmit power is 26dBm into a built-in 18dBi dish antenna, so the EIRP of the stock unit set for the USA would be too high at 26+18=44dBm in the USA.   And yet it's all set to the defaults (I didn't change the transmit or antenna value since it's the stock unit that comes with the antenna).   BEFORE: <http://wetakepic.com/images/2017/10/29/01_PB400_firmware_update_krack.jpg>   AFTER: <http://wetakepic.com/images/2017/10/29/14_PB400_firmware_update_krack.jpg>   Of course, the AirOS firmware could secretly throttle the EIRP to 30dBM (or whatever the USA legal limit is); but why would AirOS report bogus number then?   What are those decibel numbers in AirOS actually *telling* me?

tb <nospam@example.invalid>: Oct 28 11:56AM -0500 I have found this old (1990!!) TV that was sold by Montgomery Ward USA. The brand on the TV is "Signature 2000".   I also have an RCA digital TV converter box (the brand is "RCA DTA800") that comes with its remote. There is no specific part number on the RCA remote.   I'm trying to pair up the RCA remote to the TV set. I tried the following 3-digit codes that I found online: 000, 001, 023, 083, 115. None of them work...   Does anyone know what the 3-digit code is? -- tb

John-Del <ohger1s@gmail.com>: Oct 28 10:13AM -0700 On Saturday, October 28, 2017 at 12:56:25 PM UTC-4, tb wrote:   > Does anyone know what the 3-digit code is? > -- > tb     Not every 1990 TV had remote control...   Assuming that it does, the only option you have is to try all 999 codes that remote will take as it appears the remote does not have a "search" feature.

rickman <gnuarm@gmail.com>: Oct 28 01:28PM -0400 John-Del wrote on 10/28/2017 1:13 PM: >> tb   > Not every 1990 TV had remote control...   > Assuming that it does, the only option you have is to try all 999 codes that remote will take as it appears the remote does not have a "search" feature.   You can turn it on and off with a TV-B-Gone   --   Rick C   Viewed the eclipse at Wintercrest Farms, on the centerline of totality since 1998

jurb6006@gmail.com: Oct 28 05:18PM -0700 Even if it is remote it might be too old.

Jeff Liebermann <jeffl@cruzio.com>: Oct 28 06:08PM -0700 >I have found this old (1990!!) TV that was sold by Montgomery Ward USA. >The brand on the TV is "Signature 2000".   Looks like you have to search by company = ward and model = Signature 2000. DirecTV remotes have a 5 digit code in their remote. <http://www.directv.com/DTVAPP/global/contentPageIF.jsp?assetId=P4380052#h:620.226>   Here's page full of Signature 2000 remotes: <https://www.replacementremotes.com/SIGNATURE-2000/Remote-Controls/> <https://www.replacementremotes.com/store/prodthumbs?ns=1&producttype=Remote+Control&categoryid=176&keyword=signature+2000>   >I also have an RCA digital TV converter box (the brand is "RCA DTA800") >that comes with its remote. There is no specific part number on the RCA >remote.   Try RC27A remote: <https://www.replacementremotes.com/rca/buy-rc27a-dta800b1-digital-tv-tuner-converter-box-remote-control>   >following 3-digit codes that I found online: 000, 001, 023, 083, 115. >None of them work...   >Does anyone know what the 3-digit code is?   Again, from DirecTV remote codes: <http://www.directv.com/DTVAPP/global/contentPageIF.jsp?assetId=P4380052#h:620.462> Also click on "find more codes". -- 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

whit3rd <whit3rd@gmail.com>: Oct 28 11:47PM -0700 On Saturday, October 28, 2017 at 9:56:25 AM UTC-7, tb wrote:   > I also have an RCA digital TV converter box (the brand is "RCA DTA800") > that comes with its remote. There is no specific part number on the RCA > remote.   Look inside the battery compartment, sometimes there's a part number there. <www.rcaaccessories.com> is a good place to start looking, if it's an RCA universal remote.

Bruce Esquibel <bje@ripco.com>: Oct 29 01:24PM > Assuming that it does, the only option you have is to try all 999 codes > that remote will take as it appears the remote does not have a "search" > feature.   I'll give ya a +1 for both of these, in 1990 remote control sets were not entirely standard issue, especially on the lower end (which MW falls into) and trying all 999 codes might be the only way.   Since Montgomery Wards didn't make their own sets, it's likely a 3rd party kind of thing. For whatever reason I want to say they mostly were rebadged Magnavox models although Hitachi and MGA (old Mitsubishi name) rings a bell also. For all I know they could of switched every model year depending who could make them the cheapest.   The "Signature 2000" is meaningless, it's like saying you own a Buick.   If there is a paper tag still on that thing with a model number, that may lead to a clue to who made it for them.   -bruce bje@ripco.com

Roger Blake <rogblake@iname.invalid>: Oct 29 01:56PM > I have found this old (1990!!) TV that was sold by Montgomery Ward USA. > The brand on the TV is "Signature 2000".   A 1990 set hardly qualifies as "old." Possibly my 1957-vintage Motorola highboy console does.   As others have pointed out it is quite possible that set did not come with a remote control. Is there a visible infrared receiver on the front?   -- ----------------------------------------------------------------------------- Roger Blake (Posts from Google Groups killfiled due to excess spam.)   NSA sedition and treason -- http://www.DeathToNSAthugs.com Don't talk to cops! -- http://www.DontTalkToCops.com Badges don't grant extra rights -- http://www.CopBlock.org -----------------------------------------------------------------------------

Andy Burns <usenet@andyburns.uk>: Oct 29 02:16PM Roger Blake wrote:   > A 1990 set hardly qualifies as "old."   Maybe not old, but it's pre-LCD, pre-digital, pre-HD, so I'd guess 99% of its contemporaries are in landfill ...

Allodoxaphobia <knock_yourself_out@example.net>: Oct 29 04:16PM On Sun, 29 Oct 2017 13:24:24 +0000 (UTC), Bruce Esquibel wrote:   > I'll give ya a +1 for both of these, in 1990 remote control sets were not > entirely standard issue, especially on the lower end (which MW falls into) > and trying all 999 codes might be the only way.   No one has yet mentioned the ultrasonic or RF remote controls....   Jonesy

oldschool@tubes.com: Oct 29 05:28AM -0600 >minute delay was that electrolytic DO behave that way. If the problem >was the caps across the diodes, that would make sense since they seem to >be the source of the noise.   One of my latest additions to the shop tools is a digital infared thermometer. They are made to measure the temperature of anything, but are sold for automotive use, such as finding a hot brake drum, or hot spot on an engine. But I have found this thing is pretty accurate on electronic components too. It has a built in laser pointer to highlight the thing it's pointed at. So it will tell the temp of a heat sink, or CPU, or even an opamp or other chip or for that matter, any component.   If you have one of them, or get one, try to get the temperature of different parts on the chassis or PCB when you first turn it on, then do the same after a half hour. Certain things will get warmer like heatsinks, power resistors, etc but if there are passive components or semiconductors getting quite warm or hot, you may want to check them further. They used to sell some sort of stuff in a can to cool parts. It might have been freon??? I used it many years ago, I have not even looked to see if they still sell it, but if it's still sold, that could help see if the sound changes when a suspected part is cooled.   I did not read this whole thread, but I think you said those disc caps across the diodes were open. I assume you mean the power rectifier diodes. I cant understand why those would open, unless you had a lightning surge in your power lines. That makes me wonder if those diodes could be a little flaky. Usually diodes are either good or bad, but lightning surges can do strange things and nothing in electronics has a 100% definite solution. Regardless what the books say, sometimes strange things happen that have no real explanation.

"pfjw@aol.com" <pfjw@aol.com>: Oct 29 05:03AM -0700 A few things:   Laser-pointer digital infra-red thermometers are interesting tool. I have used one for many years to determine air discharge temperature, true temperatures of heating elements water temperature and the like. Whereas they are reasonably accurate, the do lack precision when it comes to small parts. For a transformer, large capacitor or even a power transistor, and at a very close range, they would be fine. Or in finding a warm area on a board, sure. But the have far to broad a view, even at a few inches to be any more accurate than that.   https://db1736767dbd5e7094bb-d61bbc5d0b342a54145a236e2d5d1ebf.ssl.cf4.rackcdn.com/Product-800x800/6dc5243f-87d8-4820-9868-667cabd4f907.jpg   Freeze spray is still with us. It is useful for tracing intermittents and components that fail when warmed up. But, be very careful with it. Cold spray hitting an overheated part or board can cause fractures - which can cause trace failure.   Whereas disc caps tend to be fairly reliable, they do fail. And given that the typical second-tier Pacific rim receiver uses parts that are at the absolute minimum edge of tolerance, that they failed is not *necessarily* an indication of an external cause. Replace them, of course. And I would suggest going to a higher voltage as well.   On the hum-when-no-input and after-some-time things. There are two things going on here. First, the failed low-value caps stopped protecting the electrolytics from the initial power surge at start-up. Again, these are marginal parts probably operating very close to their voltage rating. If you were to put an ESR meter across them it would be revealing. What is happening is that as they heat up - my guess anyway having seen it often enough before - internal perforations in the foil open up and the cap very slowly starts to short, and capacitance drops severely. The hum is at a very low level, masked as soon as a signal is present. And, does the receiver have an AVC function? There are some Surround Sound TV-types that do, such that when input signal level drops, the pre-amp function raises the volume. Which would amplify any residual hum.   You are on-target, caps and caps.   Peter Wieck Melrose Park, PA

etpm@whidbey.com: Oct 29 09:13AM -0700 >but lightning surges can do strange things and nothing in electronics >has a 100% definite solution. Regardless what the books say, sometimes >strange things happen that have no real explanation. IR thermometers are pretty handy but can give wildly false readings. This is because of the emissivity of the surface being measured. For example, bare aluminum will measure muich cooler than it really is when the temp is measured with an IR thermometer while black anodized aluminum will measure pretty accurately when the IR thermometer is used. Eric

harry newton <harry@is.invalid>: Oct 29 12:11PM How does this colloquial summary for my family look - in case you want to send one to YOUR family? ======== People are asking what to do about the KRACK Attack vulnerability (note the pleonasm), so I figured I'd let everyone know what it is & I figured I'd give folks the opportunity to ask question if they're concerned.   The canonical site for the attack is written by the white hat who found it: <https://www.krackattacks.com/>   Here's my ad-hoc summary, written with respect to what you and I need to know & do.   1. In May, the white hat notified the government & vendors he found a bug in all WPA WiFi (e.g., WPA2) where someone who is *close* enough to intercept the signals can see everything you do.   2. It affects all WiFi but the worst affected is Android at or over version 6, macOS, Linux, and really fast (i.e., 802.11r fast roaming) routers set up as repeaters (i.e., as a second router).   Far less affected are iPhones, WiFi iPads, WiFi iPods, older Android devices, Windows computers, and normal routers (e.g., 802.11n or 802.11ac), especially if they're set up as the main router (and not as a repeater).   3. There is only one viable solution, which is to *update* your device firmware or software, whether that be a mobile phone, a laptop, a desktop, a router working as a repeater, or the main router.   The order of priority should be: a. If you have Android 6+, then you *should* update soon. b. If you have MacOS or Linux, then you should update soon. c. If you have an 802.11r router, then you should update soon.   You can take your sweet time on everything else, but everything needs to be updated.   4. The problem, of course, is *how* to update each device. a. First look for your device to see if there is an update <https://www.kb.cert.org/vuls/id/228519> b. Then try to find the update <http://www.zdnet.com/article/here-is-every-patch-for-krack-wi-fi-attack-available-right-now/> c. Then update.   What a pain. Let me know if you have questions. ========

William Unruh <unruh@invalid.ca>: Oct 29 02:47PM > 1. In May, the white hat notified the government & vendors he found a bug > in all WPA WiFi (e.g., WPA2) where someone who is *close* enough to > intercept the signals can see everything you do.   No, whose interception point is close enough. Thus your wirelessly connected fridge, which usually has attrocious security, could possibly be used as an interception point for an attacker who is in Mongolia say.     > 2. It affects all WiFi but the worst affected is Android at or over version > 6, macOS, Linux, and really fast (i.e., 802.11r fast roaming) routers set > up as repeaters (i.e., as a second router).   All wifi is susceptible, including Windows. The problem with Android and Linux is they all use wpa_supplicant and it has a problem that, for security, it zeros the password after using it. But that means that when the replay occurs it uses that 0 password. Thus fixing wpa_supplicant fixes the problem, and it has in principle been fixed. Of course one needs to get that fixed version into the devices.     > Far less affected are iPhones, WiFi iPads, WiFi iPods, older Android > devices, Windows computers, and normal routers (e.g., 802.11n or 802.11ac), > especially if they're set up as the main router (and not as a repeater).   The problem is a client side problem. But all of those devices are susceptible to at least some version of Krack, and should not assumed to be "far less affected". They are all affected. That they do not have the "zero password" problem is irrelevant since they have other attack vectors.     > 3. There is only one viable solution, which is to *update* your device > firmware or software, whether that be a mobile phone, a laptop, a desktop, > a router working as a repeater, or the main router.   Yes, for all of them, not just Linux and Android.   > a. If you have Android 6+, then you *should* update soon. > b. If you have MacOS or Linux, then you should update soon. > c. If you have an 802.11r router, then you should update soon.   If you have any wireless device you should update soon. I have no idea why you are categorizing them.     > You can take your sweet time on everything else, but everything needs to be > updated.   Why in the world would you say you can take your sweet time on them. They are all vulnerable.     > <http://www.zdnet.com/article/here-is-every-patch-for-krack-wi-fi-attack-available-right-now/> > c. Then update.   > What a pain. Let me know if you have questions.   So, 4 is the only thing you really need to say. Of course how you are going to update your fridge or your toaster is a bit obscure. Do you really want a "owned" wifi device anywhere on your internal network?

harry newton <harry@is.invalid>: Oct 29 03:33PM He who is William Unruh said on Sun, 29 Oct 2017 14:47:35 -0000 (UTC):   > No, whose interception point is close enough. Thus your wirelessly > connected fridge, which usually has attrocious security, could possibly > be used as an interception point for an attacker who is in Mongolia say.   Interesting point. Thank you for that observation.   I think what you're saying is that if they can get to *any* of your devices, over the Internet, then, *from those devices*, they can intercept your traffic to, for example, your Linux laptop or Android smart phone.   But I'm confused about the risk in that case.   Are they only intercepting from the refrigerator-to-the-client-device? Or are they then able to get from your router-to-your-client-device?   (The latter would be more dangerous.)   > the replay occurs it uses that 0 password. Thus fixing wpa_supplicant > fixes the problem, and it has in principle been fixed. Of course one needs > to get that fixed version into the devices.   Here is a writeup I made for my family that others can use which shows just *one* example of fixing a WiFI device. In this case, it's a Ubiquti radio set up as an access point and only going about a half kilometer, but it could be set up to go for miles (as some of my other radios are set up).   (0) Log into your radio <http://wetakepic.com/images/2017/10/29/00_PB400_firmware_update_krack.jpg>   (1) Check the firmware version (noting the board revision, e.g., XW) <http://wetakepic.com/images/2017/10/29/01_PB400_firmware_update_krack.jpg>   (2) Hit the "Check Now" button to see if you can update from here <http://wetakepic.com/images/2017/10/29/02_PB400_firmware_update_krack.jpg>   (3) If not, go to the manufacturer's web site to locate the firmware file <http://wetakepic.com/images/2017/10/29/03_PB400_firmware_update_krack.jpg>   (4) You may have to agree to the manufacturer's updated EULA <http://wetakepic.com/images/2017/10/29/04_PB400_firmware_update_krack.jpg>   (5) Download the file to a known location on your computer <http://wetakepic.com/images/2017/10/29/05_PB400_firmware_update_krack.jpg>   (6) Save the file in a logical location on your computer for future use <http://wetakepic.com/images/2017/10/29/06_PB400_firmware_update_krack.jpg>   (7) Then in the radio, press the "Upload Firmware Choose File" button <http://wetakepic.com/images/2017/10/29/07_PB400_firmware_update_krack.jpg>   (8) Wait for the firmware to upload (it may take a minute or two) <http://wetakepic.com/images/2017/10/29/08_PB400_firmware_update_krack.jpg>   (9) Once uploaded, press the "Update" button to update the firmware <http://wetakepic.com/images/2017/10/29/09_PB400_firmware_update_krack.jpg>   (10) Wait for the firmware to be updated (it may take a minute or two) <http://wetakepic.com/images/2017/10/29/10_PB400_firmware_update_krack.jpg>   (11) Do not power down while you are waiting for the firmware to update <http://wetakepic.com/images/2017/10/29/11_PB400_firmware_update_krack.jpg>   (12) When done, the radio will reboot; log back in to check results <http://wetakepic.com/images/2017/10/29/12_PB400_firmware_update_krack.jpg>   (13) You should note that the firmware should now be updated <http://wetakepic.com/images/2017/10/29/13_PB400_firmware_update_krack.jpg>   (14) Doublecheck now that everything is updated that it is working fine <http://wetakepic.com/images/2017/10/29/14_PB400_firmware_update_krack.jpg>   > So, 4 is the only thing you really need to say. Of course how you are > going to update your fridge or your toaster is a bit obscure. Do you > really want a "owned" wifi device anywhere on your internal network?   I have over a dozen WiFi devices in my house.... so I'm updating them one by one. I'm more worried about my grandchildren not knowing how to update *their* devices, and my older siblings, etc.   But I agree, it's a PITA to update *every* WiFi device in the house. I have over a half-dozen access point radios, for example, and a few on the roof, etc., some of which connect by WiFi to homes that are 10 miles away, so it's a pain for any of them.

"Ian Field" <gangprobing.alien1@virginmedia.com>: Oct 28 10:04PM +0100 "micky" <NONONOmisc07@bigfoot.com> wrote in message news:6pd2vc5lpdrjldhcphs4c85s5lkbgo337p@4ax.com... > as a wrench did with the hex nut, and pliers will scratch it up.   > I could find an old hex nut, but I'd rather use the pretty round one, > if I can.   The usual procedure involves the treaded boss being longer than you need, you tighten up against a hex nut behind the panel and not the switch itself. So you would screw the knurled nut on so the thread is only just not showing, then tighten the hex nut behind the panel.   In the metal shop segment in my first year at college, one of the exercises was fabrication of a spanner with one jaw serrated and the other smooth. This would do either knurled or hex nuts. Can't remember seeing any commercially produced, but I can't remember ever bothering to look.   For hex nuts on front panels, one company had specially made spark-eroded tools. literally a length of steel bar, drilled through to accommodate the threaded boss and spindle. The hex recess was spark eroded just shallower than the nut so the tool never touches the panel.

tabbypurr@gmail.com: Oct 29 03:53AM -0700 On Friday, 27 October 2017 04:58:51 UTC+1, micky wrote: > squeezed too hard and scratched the chrome. I think it was only a > little, but memory plays tricks on mpeople. And it didn't tear the > cloth but it still scratched, and that surprised me.   cloth isn't good for such things, as it's full of holes and most cloth collapses very easily. Card is better.     NT

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ehsjr <ehsjr@mverizon.net>: Oct 27 11:03PM -0400 On 10/21/2017 8:50 PM, Clifford Heath wrote: > friction pad touches it. You could try getting some Penetrene > into the bearings, but the right fix is to disassemble, clean > and lubricate it.   Here's a video on the motor clutch - it might help: https://www.youtube.com/watch?v=WfZS7hHBd7s   Ed

Ivan Vegvary <ivanvegvary@gmail.com>: Oct 28 06:38AM -0700 Back in the late '70s I was paying $12-1300 for used selectrics. Those were real dollars. Hurts to see them at garage sales for $5-10. Wonderful machines!

Foxs Mercantile <jdangus@att.net>: Oct 28 09:14AM -0500 On 10/28/2017 8:38 AM, Ivan Vegvary wrote: > Back in the late '70s I was paying $12-1300 for used > selectrics. Those were real dollars. Hurts to see > them at garage sales for $5-10. Wonderful machines!   Some time ago, I read a wonderful article about them. "The invention nobody needed."   After their introduction, it seemed like EVERY office in the US replaced their old mechanical typewriters.   In my Junior year in high school I took a typing class. Being good at it I was allowed to use one of the IBM Selectrics. 65 WPM here we come!   You'll never fully appreciate doing a two column full justification on a PC unless you've done it by hand with a typewriter and a red pencil. ;-)       -- Jeff-1.0 wa6fwi http://www.foxsmercantile.com

Tim R <timothy42b@aol.com>: Oct 27 05:24PM -0700 > >> of space in comparison to optical or laser levelling to good old benchmarks.   > >Unless you have a warm air layer in between refracting your line of sight.   > Working near a very, very hot room and opening the doors to the cold, cold outside can cause that visual effect.   There is a rather famous case where tunnels were supposed to meet from each side of a mountain, but didn't. Analysis showed they'd relied on a laser level, and it had been bent by a warm air layer in the path.

Ivan Vegvary <ivanvegvary@gmail.com>: Oct 28 06:50AM -0700 Any surveyor can calibrate quickly with no instrumentation. Set level tripod almost exactly between two objects approximately 200ft apart. Make a mark on each object (rotate 180deg back and forth). Said marks will be exactly at the same elevation. Move level (4-5ft) close to one mark, sight it, rotate to second mark (200ft away) and hope to read the same relationship. Adjust bubble accordingly, and repeat entire procedure.

bruce2bowser@gmail.com: Oct 28 07:10AM -0700 I think that imaging using electromagnetic radiation or waves has come quite a ways, too.

dplatt@coop.radagast.org (Dave Platt): Oct 27 11:09AM -0700 >did the hum not show up immediately upon turning on the receiver rather >than after 1/2 hour? I enjoy solving a problem, but I always like to >fully understand it. Thanks.   At a guess, the caps probably undergo some amount of thermal cycling as the receiver warms up (when turned on) and cools down (when turned off). The temperature changes cause the material of the caps (and the leads) to expand and contract, creating a temperature-dependent physical stress on the cap body (the leads are soldered down and their ends can't move, and so stress is created where the leads enter the body and where the leads are soldered to the board).   Over time, this repeated stress ended up weakening and cracking something in the caps - possibly the dielectric itself, possibly the dielectric-to-wire bonds. It's also common for the component itself to be OK, but for a stress crack to occur in the solder joint where its leads connect to the PC board or solder terminals.   Apparently, when the receiver warms up, the thermal expansion is enough to cause this crack to open up. When the receiver down, the cracked junction is pressed back together enough to "close the circuit" again.   Replacing the parts with known-good subsitutes, after cleaning off the older solder from the junction, and re-soldering carefully with the right type of solder and (often useful) some extra liquid solder flux, is the right fix.   Problems of this sort can sometimes be found by tapping various components gently with a wooden chopstick... when you find the area of the cracked component or solder joint, a test speaker hooked to the receiver will start making dreadful popping and banging noises, or the problem will appear and disappear. Don't do this with a speaker you care about :-)

Ken <Ken@invalid.com>: Oct 27 02:03PM -0500 Dave Platt wrote: > receiver will start making dreadful popping and banging noises, or the > problem will appear and disappear. Don't do this with a speaker you > care about :-)   I figured it must be heat related, but your explanation was precise and probably correct. Thanks.

jurb6006@gmail.com: Oct 27 12:26PM -0700 Actually lytics are worse when cold, the opposite of your situation.

Ken <Ken@invalid.com>: Oct 27 08:25PM -0500 > Actually lytics are worse when cold, the opposite of your situation.   The caps I was thinking of were disc caps across the diodes, not electrolytics elsewhere in the circuit. What puzzled me about the 30 minute delay was that electrolytic DO behave that way. If the problem was the caps across the diodes, that would make sense since they seem to be the source of the noise.

Peabody <waybackNO584SPAM44@yahoo.com>: Oct 27 12:00PM -0500 It's an old Sears garage door opener. The schematic shows a 50 ufd start capacitor. What's in there now is 43-52 ufd. What I've found locall to replace it is 53-64 ufd. Will that work?

Fred Smith <fred@thejanitor.corp>: Oct 27 10:27PM > It's an old Sears garage door opener. The schematic shows a 50 ufd start > capacitor. What's in there now is 43-52 ufd. What I've found locall to > replace it is 53-64 ufd. Will that work?   Probably... But the wrong capacitor value may make the motor not spin up at all, or go in reverse instead.

M Philbrook <jamie_ka1lpa@charter.net>: Oct 27 07:18PM -0400 In article <20171027-170008.854.0@Peabody.ssl.astraweb.com>, waybackNO584SPAM44@yahoo.com says...   > It's an old Sears garage door opener. The schematic shows a 50 ufd start > capacitor. What's in there now is 43-52 ufd. What I've found locall to > replace it is 53-64 ufd. Will that work?   YES Those values are not critical for that application.

Foxs Mercantile <jdangus@att.net>: Oct 27 06:51PM -0500 On 10/27/2017 6:18 PM, M Philbrook wrote: >> replace it is 53-64 ufd. Will that work?   > YES > Those values are not critical for that application.   Right. A start capacitor has a minimum value at which it work work. The ones that are critical are the run capacitors. And even then, 10-20% will usually work, 100% might, but the motor will run hot.   -- Jeff-1.0 wa6fwi http://www.foxsmercantile.com

micky <NONONOmisc07@bigfoot.com>: Oct 27 12:58PM -0400 In sci.electronics.repair, on Thu, 26 Oct 2017 22:26:38 -0700, mike >I'm sure you will never let anyone else drive your car...until it >happens. The person who buys it at your estate sale might be surprised >when he accidentally pops the top at highway speed.   One more thing. Every car I've had except one 47 years ago (that I sold because my brother gave me a convertible) and my immediately preceding car, that I still have, has gone to the junk man after it left me. Even the one I still have, I might not be able to find someone who will both buy and repair.   I was going to list this as the first reason there is no danger in my cutting the wire from the speedometer to the top motor, but I'll admit that maybe I'll raise my standard of living by the time I'm 75 and not drive my car until it falls apart, like I always have. And of course if I die, there's no special reason to think the car will be a junker then, but my plan is to live much longer than this car will last. ;-)   (Of course and otoh, even if I outlive this car, I'll cut the same wire on the next four cars, every 5 years instead of 7 like it's been, if I still have the strength to do it. It was tedious and tiring to kneel on the ground for a total of an hour or more and twist my body to look at the wires behind the kick panel, but all in all, it was still easy. I hear a time is coming when I'm 90 or 95 that I won't be able to do this. Maybe I could hire someone, but that is so expensive. ;-) )

micky <NONONOmisc07@bigfoot.com>: Oct 27 01:14PM -0400 In sci.electronics.repair, on Fri, 27 Oct 2017 12:23:14 -0400, Tom Biasi >> little [bit of a scratch], but memory plays tricks on mpeople. And it didn't tear the >> cloth but it still scratched, and that surprised me.   >That's why they make strap wrenches.   I didn't know about that in those days. I only had the tools and parts my father had bought when he was alive. We went to the hardware store some times but I never even looked in the tool section.   When the battery on the '52 Hudson was dead every night, and I had to take my mother's car to my summer job, the only test equipment I had was a socket with a 110 volt light bulb, lamp cord, and an ice pick. It actually was enough, and since there were no transistors then (1964), at least not in cars, not in 1952 cars, I didn't hurt anything.   There were also no quick connectors so every time I had to disconnect a wire, I had to unscrew something, all of it under the dash.

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