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"Ron D." <ron.dozier@gmail.com>: Sep 19 10:32PM -0700 I agree with Peter. 240/30e-3 = 8K BTW   Metal Oxide resistors usually totally break in half under overload.   Maybe they should have raised it off the board,   They could have not taken into account the voltage rating: See http://www.hkresistors.com/-products-flameproof-type-metal-oxide-film-resistor.html for an example.   240 * 1.4 = 336 V (0 to peak)

N_Cook <diverse@tcp.co.uk>: Sep 20 08:45AM +0100 On 20/09/2017 06:32, Ron D. wrote:   > Maybe they should have raised it off the board,   > They could have not taken into account the voltage rating: See http://www.hkresistors.com/-products-flameproof-type-metal-oxide-film-resistor.html for an example.   > 240 * 1.4 = 336 V (0 to peak)   I think that is the most likely, HV breakdown , perhaps 2x220K in series would not have failed but 1x450K would. The item was stored indoors , no damp involvement. But it seems a bit odd that dozens of times tested in use and then fails after an extended period of non-use. Perhaps stressing while in use, cracking the casing , then a film of mould or something organic can grow over the MO surface in storage.

"pfjw@aol.com" <pfjw@aol.com>: Sep 19 09:54AM -0700 I participate in the occasional radio-club related repair clinic, and give one twice a year in Kutztown, teaching basic diagnostic and repair techniques for vintage radios and electronics from the 1920s to approximately the 1990s. There are some basic rules for the protection of the clinician and the 'customer'.   a) Do not take money. Do not imply Fee-for-Service. The moment money is taken, there is an expectation of professionalism and expertise that conveys a level of liability.   b) Make it clear that you are doing this as a hobby, and that you are demonstrating technique and skills that may be useful to the customer in their future endeavors along the same hobby-related lines.   c) If parts are to be replaced, those parts *must* be obtained and supplied by the customer. Pointing to possible sources is OK, as long as you are able to point to more than one.   d) If power must be applied to an item during the process, the source must be isolated, and you must explain to the customer the reasons for it, and advise him/her why this is so.   e) Kluge repairs left in place are not acceptable, full stop. For instance, if one jumps out a damaged 'fuse resistor' to determine whether replacing it is worthwhile and the customer does not have the actual replacement - you may go as far as to suggest that the item is repairable - but not here, and not without the proper parts. Remove the jumper.   Whether or not an organization has "insurance cover', should there be an unfortunate event, the individual tech involved will remain involved whether liable for actual damages or not. And whereas most individuals are sincere and mean no harm, a fire, shock or other occurrence will change even the most gentle person.   I will teach technique, and I will show individuals how to make their own basic repairs such as re-capping, cleaning and similar. I will point them to books, manuals and sources. But in a situation where one is dealing with the *GENERAL PUBLIC*, I will take nothing for granted.   Peter Wieck Melrose Park, PA

N_Cook <diverse@tcp.co.uk>: Sep 20 08:40AM +0100 > I will teach technique, and I will show individuals how to make their own basic repairs such as re-capping, cleaning and similar. I will point them to books, manuals and sources. But in a situation where one is dealing with the *GENERAL PUBLIC*, I will take nothing for granted.   > Peter Wieck > Melrose Park, PA   I think I'll print-off that piece and take it with me. If I have to assess the owner as to technical/elfin-safety competance, I'll have a pre-prepared UK mains plug and bit of lead with very specific posed faults, and get him to point them out.

ggherold@gmail.com: Sep 19 11:40AM -0700 On Tuesday, September 19, 2017 at 11:01:27 AM UTC-4, Jeff Liebermann wrote:   > Well, you could try bouncing the cells: > <http://gizmodo.com/an-amazingly-simple-way-to-test-if-a-battery-is-dead-1138197569> > <https://lifehacker.com/test-if-your-batteries-are-dead-by-dropping-them-on-a-h-1630525062>   That second one is good. (I'd say they figured it out.)   For alkaline, I just measure the open circuit voltage... that seems to be good enough for me. 1.6 fully charged, 1.4 OK, 1.2 or less pitch it.   George H.

Jeff Liebermann <jeffl@cruzio.com>: Sep 19 02:52PM -0700 On Tue, 19 Sep 2017 07:20:39 -0700 (PDT), captainvideo462009@gmail.com wrote: > Can someone please tell me what the appropriate loads would be.   Looks like the consensus is 10 ohms 5 watts for all the 1.5v batteries: <https://electronics.stackexchange.com/questions/179303/what-resistance-load-do-battery-testers-aa-or-aaa-use-in-ohms-please> However, Googling around, I'm finding schematics and recommendations varying from 8 ohms to 15 ohms.   -- 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

Phil Allison <pallison49@gmail.com>: Sep 19 05:27PM -0700 > I would like to test my 9V, C, D, AA, and AAA under the proper load.   ** The ESR of a cell or battery is a good guide to its condition.   A fresh AA alkaline measures 0.1 ohms or lower while a tired one measures 1 ohm or greater, a fresh 9V measures under 1 ohm. Along with a voltage test you have enough info to match or discard used cells.   .... Phil

gregz <zekor@comcast.net>: Sep 20 07:09AM > measures 1 ohm or greater, a fresh 9V measures under 1 ohm. Along with a > voltage test you have enough info to match or discard used cells.   > .... Phil   What's a good way to do that ?   Greg

Phil Allison <pallison49@gmail.com>: Sep 20 12:33AM -0700 GS wrote:   -------------------- > > voltage test you have enough info to match or discard used cells.   > > .... Phil   > What's a good way to do that ?   ** Do what ?   Test ESR or correlate it with open cct cell voltage?       .... Phil

micky <NONONOmisc07@bigfoot.com>: Sep 19 09:19PM -0400 I've been reading about a car like mine and the owner says that the rear subwoofer is "blown". I always took that to refer to an electrical open. Does that ever happen?   But does it also refer to a torn surround?

dansabrservices@yahoo.com: Sep 19 06:54PM -0700 On Tuesday, September 19, 2017 at 9:19:37 PM UTC-4, micky wrote: > subwoofer is "blown". I always took that to refer to an electrical > open. Does that ever happen?   > But does it also refer to a torn surround?   Typically a "blown" speaker can mean that either the voice coil is open or that the surround is torn which will result in distorted sound. Either can be fixed, it is just a matter of how much the cost will be. If the surround is torn, it can be easily replaced. While the coil can also be replaced, it is a much more involved task that requires some finesse. These days, consumer speakers found in cars are usually replaced rather than repaired as that option is cheaper.   Dan

Phil Allison <pallison49@gmail.com>: Sep 19 07:01PM -0700 micky wrote:   > I've been reading about a car like mine and the owner says that the rear > subwoofer is "blown".   ** Blown = destroyed.     > I always took that to refer to an electrical > open. Does that ever happen?   > But does it also refer to a torn surround?   ** There are many way a speaker can be damaged and rendered useless.   http://sound.whsites.net/articles/speaker-failure.html#s5     .... Phil

John-Del <ohger1s@gmail.com>: Sep 19 07:07PM -0700 On Tuesday, September 19, 2017 at 9:19:37 PM UTC-4, micky wrote: > subwoofer is "blown". I always took that to refer to an electrical > open. Does that ever happen?   > But does it also refer to a torn surround?   Any kind of failure falls under the description of "blown".   Open, intermittent, shorted, or melted/shifted voice coil or weak or damaged surrounds all fit that description.   "Blown" has become a catch-all for *any* kind of failure, even medical: "I blew my back out swing a bat. I won't be able to play for several days"..

micky <NONONOmisc07@bigfoot.com>: Sep 19 11:23PM -0400 In sci.electronics.repair, on Tue, 19 Sep 2017 19:07:01 -0700 (PDT),   >Any kind of failure falls under the description of "blown".   >Open, intermittent, shorted, or melted/shifted voice coil or weak or damaged surrounds all fit that description.   >"Blown" has become a catch-all for *any* kind of failure, even medical: "I blew my back out swing a bat. I won't be able to play for several days"..     Thanks, you, dan, and phil. I guess I have to update my view of the word.   I can't remember if I got back to you about this:   Toyota Solara convertible, when they were still made, used a woofer behind the front seat. The paper surround had fallen apart and after discussing it here, I replaced it with one from SimplySpeakers. It was very easy. Their instructions don't require centering the cone, except iirc by pushing it down and up, or up and down, once.   And the glue they provided was very good. Like Duco Cement from the 60's but better.   So the speaker goes in and works fine, but now there is too much bass. I turned down the bass, but I could still hear it even during talk shows like Terry Gross and the news. Other things broke and I got a new car but I think the reason mine had had one of the voice coil wires cut was to cut down the bass, and when that wasn't enough they unplugged the whole thing. I repaired the cut wire and now I sort of regret that!

micky <NONONOmisc07@bigfoot.com>: Sep 20 01:39AM -0400 In sci.electronics.repair, on Tue, 19 Sep 2017 23:23:20 -0400, micky   >Toyota Solara convertible, when they were still made, used a woofer >behind the front seat.   I mean behind the rear seat. I didn't even know it was there until I took the seat back out for some other reason.

micky <NONONOmisc07@bigfoot.com>: Sep 20 01:38AM -0400 I'm looking for a replacemwent car radio, and this one says it has "analog TV". I know that means it can play the image from its rear-view camera, but what other sources of analog TV exist? (I know there are still, or were, low-power analog tv stations but I mean "could exist be provided to this device".)   It also says it plays many formats including "DVD, DVD-RAM", so that means IIUC it can play a digital DVD video? So analog TV must be in addition to that?   FWIW, here's the whole ad http://www.ebay.com/itm/Sony-Lens-Double-2Din-7-Car-Stereo-Radio-DVD-Player-iPod-Bluetooth-TV-MP3-Mic-HD-/142486326437?_trksid=p2141725.m3641.l6368

Geo <nhhu-o3hu@dea.spamcon.org>: Sep 19 08:40PM +0100 >https://www.dropbox.com/s/x8lvblyq4qyn8me/PU-1D%20mod%202.jpg?dl=0   >I think (because it's wrapped up in tape) there is a big electrolytic >cap in there as well.   Can't see all the components, or be sure of the colours on those brown bodied resistors but my reverse eng sketch is here:- http://tinypic.com/r/24v3zm0/9   Looks like a similar version to :- http://spritesmods.com/?art=wtcpled&page=2 detecting the transformer volts drop when the switch closes.

T i m <news@spaced.me.uk>: Sep 20 12:48AM +0100 On Tue, 19 Sep 2017 20:40:33 +0100, Geo <nhhu-o3hu@dea.spamcon.org> wrote:     >Can't see all the components, or be sure of the colours on those brown >bodied resistors but my reverse eng sketch is here:- >http://tinypic.com/r/24v3zm0/9   Woah, that's amazing Geo, just from those two pictures. ;-)   Would you like me to confirm what the missing values are (the vertical component and the cap)?   >Looks like a similar version to :- >http://spritesmods.com/?art=wtcpled&page=2 >detecting the transformer volts drop when the switch closes.     Yeah, I think I remember that being the only way we worked out we could do it back then (well, not without a current shunt of some sort etc).   It's funny, after making and fitting it I'd sorta forgotten I had ... because it was out of sight and 'just worked'. ;-)   The PCB was just stuffed into a little zip top component bag and it all bundled in there and the base put back on. I probably intended doing it properly sometime but ... ;-)   Cheers, T i m

Chris Jones <lugnut808@spam.yahoo.com>: Sep 20 02:21PM +1000 On 19/09/2017 08:47, T i m wrote: > elegant (especially the soldering as I was probably supposed to be > 'working' when I did it). ;-)   > Cheers, T i m   Thanks!

"pfjw@aol.com" <pfjw@aol.com>: Sep 19 10:07AM -0700 On Friday, September 8, 2017 at 3:19:11 PM UTC-4, Ralph Mowery wrote:   > life insurance to pay off. Or is someone gets hurt in a car crash > without the seat belt, just do not pay off for medical bills or to get > his car repaired.   Some pretty serious issues here if this is to be enforced.   a) Automakers must be then, 100% liable *forever* for the functionality of the seat belts and safety devices. So, latches that fail, belts that wear and break, and airbags that do not go off - none of which are user-serviceable - must fall back on the manufacturer. b) Seat belt and safety device deployment must then be recorded in the automotive 'brain' such that this will indicate at the crash-investigation stage. Similar to an aircraft flight data recorder. Many of these even now record speed and other conditions if there is a crash, some will even notify emergency services.   Which, of course, will naturally lead to insurance companies demanding 'good driver' monitors on their insured that continuously relay speed/braking/timing/and much more to the company so that they may determine 'risk' based on actual driving behavior. Some offer this option right now.   Is that what you really want?   Peter Wieck Melrose Park, PA

"Percival P. Cassidy" <Nobody@NotMyISP.net>: Sep 19 01:52PM -0400 On 09/08/2017 02:42 PM, rickman wrote:   > than the gallon used in the US.  I don't know if there are other > differences, I'm pretty sure the inch, foot and yard are the same.  I'm > not sure if a fortnight is the same on both sides of the Atlantic... ;)   A US gallon is smaller than an Imperial gallon because the US pint has the wrong number of fluid ounces (16 instead of 20).   > We use the term "English units" because like many of our customs, laws > and general ways of life, they came to us by way of England.   When it comes to tools such as wrenches, I see the term "Standard" often used in the USA -- maybe just short for the whole "SAE" term, the last two of whose letters I don't recall the meaning.   Perce

"Percival P. Cassidy" <Nobody@NotMyISP.net>: Sep 19 02:05PM -0400 On 09/07/2017 01:16 AM, rickman wrote: >> head> >> US water must be heavier.   > A pint's a pound the world around!   No, it isn't. Even if we stick to the undersized US pints of 16 fl.oz. instead of 20 fl. oz., the weight of something with a volume of one pint varies considerably depending on what the substance is. Even if we're talking about cooking and trying to convert recipes with quantities by weight to cup measurements, a cup of sugar and a cup of flour probably will not weigh the same, and the weight of the flour will depend on how densely it's packed -- could be as little as 5 oz. rather than the 8 oz. that the "pint's a pound the world around" formula indicates.   Perce

"pfjw@aol.com" <pfjw@aol.com>: Sep 19 11:03AM -0700 On Tuesday, September 19, 2017 at 1:50:18 PM UTC-4, Percival P. Cassidy wrote:   > When it comes to tools such as wrenches, I see the term "Standard" often > used in the USA -- maybe just short for the whole "SAE" term, the last > two of whose letters I don't recall the meaning.   S ociety of A utomotive E ngineers   N ational S cience F oundation   N ational P ipe T aper   A merican S ociety for T esting M aterial   N ational F ire P rotection As sociation   N ational E lectrical C ode   N ational S tandard P lumbing C ode   A merican S ociety of H eating, R efrigerating and A ir-Conditioning E ngineers   There are many.   Peter Wieck Melrose Park, PA

"pfjw@aol.com" <pfjw@aol.com>: Sep 19 11:05AM -0700 Forgot: A merican W ire G auge

rickman <gnuarm@gmail.com>: Sep 19 11:18PM -0400 Percival P. Cassidy wrote on 9/19/2017 2:05 PM: > not weigh the same, and the weight of the flour will depend on how densely > it's packed -- could be as little as 5 oz. rather than the 8 oz. that the > "pint's a pound the world around" formula indicates.   You have eyes, but can not see.   --   Rick C   Viewed the eclipse at Wintercrest Farms, on the centerline of totality since 1998

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