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Jon Elson <elson@pico-systems.com>: Jul 15 01:13PM -0500 ABLE1 wrote:     > could the electrolyte leach into the chips at the pins and cause > problems with the chip in some way?? Or is the chip considered > hermetically sealed is some fashion?? The typical commercial chips are epoxy molded around the lead frame and IC. So, the "seal" is just metal leads molded into the plastic body. Given enough time and humidity, it is possible for the leaked electrolyte or any other corrosive stuff to work its way along the lead and get to the bonding wires or the IC itself. Not real common, but it CAN happen.   Military/aerospace chips are more hermetic, with kovar leads fused into a glass seal. But, enough corrosive stuff can get into those, too. it just takes longer.   Jon

ABLE1 <someone@nowhere.net>: Jul 15 04:39PM -0400 On 7/15/2017 2:13 PM, Jon Elson wrote: > glass seal. But, enough corrosive stuff can get into those, too. it just > takes longer.   > Jon   Thanks Jon,   I understand. At this point I am going to replace the caps and see what happens. Hopefully that will be the complete fix.   Les

tabbypurr@gmail.com: Jul 15 05:53PM -0700 On Saturday, 15 July 2017 17:25:07 UTC+1, ABLE1 wrote:   > Thanks NT,   > I got it. Was just wondering if the "seal" would be > effected by the leaking electrolyte is some way.   as said it's epoxy on metal so not likely.   > As a general question on these capacitors that leaked. > Given the age (20+ years) would it be that they would > have been effected by a power surge or just old age.   old age and/or lack of power   > and value that do not show any leakage.   > I am asking in respect that given the condition should I > just replace them all or only those that have leaked??   Given the bad state of some caps it's likely there are others that have gone high ESR and/or low capacity but not leaked. Most folk would replace the lot. You can get a £12 chinese component tester that'll tell you real capacity & ESR. See ebay, amazon, banggood etc.     NT

Phil Allison <pallison49@gmail.com>: Jul 16 04:51AM -0700 ABLE1 wrote:   --------------------   > Or similar, but may not be the most desired.   > Phil, as for the term "Circuit Board Cleaner" is there a specific brand > that you use??   ** The brand I use is " RF " ( Richard Foot Pty Ltd ), available only here in Australia, AFAIK   The CRC product you linked is likely similar - simple, fast evaporating hydrocarbon solvent.     .... Phil

"David Farber" <farberbear.unspam@aol.com>: Jul 15 08:01PM -0700 Here is a picture of the toy: http://www.pet2go.co.uk/wp-content/uploads/2016/03/Interactive-Mouse-Chaser-Toy-Revolving-Moving-Mouse-Motion-Game-Cat-Kitten.jpg   I removed the small motor that looks about the size of a CD spindle motor. It measured around 1-2 ohms across its terminals. When I hooked it up to my bench supply with the current limiter set to 0.5 amps, the overload kept tripping. I was able to remove the motor from its case and give the brushes a good cleaning. Now the motor works fine from my bench supply but in circuit, it's still not working. I traced the circuit back to two pairs of SMD transistors. They are very hard for me to see even with my magnifiers. I think one of them has a crack in it. The only writing on the first pair is :Y1 and the other pair is marked, :Y2 Any ideas what kind of transistors or other three-terminal devices these are?   Thanks for your reply. -- David Farber Los Osos, CA

tabbypurr@gmail.com: Jul 16 02:31AM -0700 On Sunday, 16 July 2017 04:02:03 UTC+1, David Farber wrote: > :Y1 and the other pair is marked, :Y2 Any ideas what kind of transistors or > other three-terminal devices these are?   > Thanks for your reply.   Those toys are hopelessly unreliable. Better to junk the controller and add a manual control. If you want to fix the controller you'll need to follow the output area circuit to work out what the connections are and whether they're npn or pnp. Most likely it'll be a standard motor driver H bridge, and they'll need replacing with devices able to take peak motor current, which you can measure.     NT

oldschool@tubes.com: Jul 15 03:15PM -0400 About 5 years ago, I bought a solar charger for charging cell phones. It seemed like a great idea, and worked fine for a year at most. Then it would charge for a minute or so, and shut itself off. It could also be charged by hooking it to a USB port on a computer or use a phone charger. It had 4 blue LEDs that were supposed to indicate the amount of charge it contained. Even after charging form a USB, it did not charge a phone anymore.   It's been sitting in a box ever since. I just connected it to a USB charger and it would not even take a charge anymore. I took it apart and was expecting to find some AA or AAA NiCd batteries, similar to the ones that are inside of those sidewalk solar lights. My plan was to replace those batteries with NiCd cells, the same way I change them in those solar lights that quit working.   When I opened it, I was shocked. Instead of AA or AAA batteries, I found two square "pouches". Sort of like tin foil covered bags that are labeled as batteries. They are flexible, squishy, and just have two contacts labeled + and - (there are two of them). I have never seen batteries like this.   Besides those weird batteries, I found a small circuit board with 6 or 7 very small IC chips. One with 16 pins, and the rest have 6 pins each. Plus an electrolytic cap, and a small coil which is probably some sort of choke, and several surface mounted things which I assume are resistors. Also the USB plugs and those 4 LEDs are connected to that board. All of this seems very complex for such a small charger, and those chips are so small I can barely see the leads on them, much less try to repair this thing. Heck, I need a magnifying glass just to see the solder joints on this thing.   The plan is to salvage the solar panel, and trash the rest of it. The solar panel is a lot bigger than the ones on those solar lights, (about 4 x 5 inches). I'm suspecting the solar panel is still good, (I will have to test it to be sure, by hooking a volt meter to it when it's in the sun).   My question is whether I can connect this solar panel directly to a rechargable battery, or do I need some sort of diode or other components between it, and the battery(s). (I know those solar lights have very minimal components). But it seems to me that there probably needs to be some sort of component (at least a diode) to protect the battery current from back-flowing into the solar panel. In the end, this will just become a solar charger for NiCd or NiMh rechargable batteries, or I might even turn it into a solar light sort of thing.   Anyhow, what is needed to attach this solar panel to a common rechargable AA or AAA battery?     Thanks!

Rheilly Phoull <rheilly@bigslong.com>: Jul 16 07:47AM +0800 > Anyhow, what is needed to attach this solar panel to a common > rechargable AA or AAA battery?   > Thanks!   It will need a controller and the batteries will need to be less volts than the cells unless a boost circuit is employed.

tabbypurr@gmail.com: Jul 15 05:58PM -0700 > Anyhow, what is needed to attach this solar panel to a common > rechargable AA or AAA battery?   > Thanks!   Likely the fault is with the squishy lithium batteries.   If you want to use just the panel, some allow dark current leakage, some don't. Hook it to a battery, put it in darkness and measure. If it leaks add a diode.   Charge control depends on battery chemistry & size. NiCd & NiMH can be charged by just limiting current delivery to C/16, so measure your panel output current in full sun as well as offload voltage. Lithium is much more fussy, hence some of the circuitry.     NT

Jeff Liebermann <jeffl@cruzio.com>: Jul 15 06:12PM -0700 >When I opened it, I was shocked. Instead of AA or AAA batteries, I found >two square "pouches". Sort of like tin foil covered bags that are >labeled as batteries.   Those are LiPo (lithium polymer) batteries, normally used in cell phones and quadcopters. Photos: <https://www.google.com/search?q=lithium+polymer+batteries&tbm=isch>   >Besides those weird batteries, I found a small circuit board with 6 or 7 >very small IC chips.   That's the charge controller.   >Heck, I need a magnifying glass just to see >the solder joints on this thing.   You'll also need specialized tools to build and repair those, such as a hot air desoldering station, reflow oven, solder paste, and various chip manipulation tools.   >4 x 5 inches). I'm suspecting the solar panel is still good, (I will >have to test it to be sure, by hooking a volt meter to it when it's in >the sun).   You might also want to measure the short circuit current. Just put an ammeter across the solar cell leads and see what you get.   >My question is whether I can connect this solar panel directly to a >rechargable battery,   No.   >or do I need some sort of diode or other components >between it, and the battery(s).   Yes, a solar charge controller. What type and size depend on the ratings of the solar panel and LiPo battery, neither of which are currently well defined.   >(I know those solar lights have very >minimal components).   They also do a great job of killing batteries. LiPo lasts longer than most, but few batteries will last very long after being cycled between full charge and total discharge every day.   >But it seems to me that there probably needs to be >some sort of component (at least a diode) to protect the battery current >from back-flowing into the solar panel.   True. Schottky diode for minimum voltage drop. It's often inside the charge controller chip.   >In the end, this will just >become a solar charger for NiCd or NiMh rechargable batteries, or I >might even turn it into a solar light sort of thing.   In the end, if you use it as a solar powered garden light, you'll likely kill the battery. You need to match the battery, charge controller, and solar cell to each other. So far, you're not doing that.   >Anyhow, what is needed to attach this solar panel to a common >rechargable AA or AAA battery?   Better numbers.   -- 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

Jeff Liebermann <jeffl@cruzio.com>: Jul 15 06:24PM -0700 >Likely the fault is with the squishy lithium batteries.   The first step to solving a problem is to blame someone or something. However, in this case, you're probably right.   >If you want to use just the panel, some allow dark >current leakage, some don't. Hook it to a battery, put >it in darkness and measure. If it leaks add a diode.   Unless the solar cells (or panel) have built in diodes, most everything I've seen exhibits dark current (leakage).   >delivery to C/16, so measure your panel output current >in full sun as well as offload voltage. Lithium is >much more fussy, hence some of the circuitry.   I beg to differ. You might be able to trickle charge NiCd, but NiMH is considerably more picky: <http://batteryuniversity.com/learn/article/charging_nickel_metal_hydride> "It is difficult, if not impossible, to slow charge a NiMH battery. At a C rate of 0.1C to 0.3C, the voltage and temperature profiles do not exhibit defined characteristics to trigger full-charge detection, and the charger must depend on a timer. Harmful overcharge can occur when charging partially or fully charged batteries, even if the battery remains cold."   In other words, C/16 or 0.06C charge rate for NiMH screws up the NVD (negative voltage detection) mechanism used to detect EoC (end-o-charge), which can easily overcharge a NiMH cell or battery.     -- 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

tabbypurr@gmail.com: Jul 16 02:28AM -0700 On Sunday, 16 July 2017 02:24:07 UTC+1, Jeff Liebermann wrote:   > >Likely the fault is with the squishy lithium batteries.   > The first step to solving a problem is to blame someone or something. > However, in this case, you're probably right.   If the OP had the skill to fault find I'd think they''d already have tried to     > In other words, C/16 or 0.06C charge rate for NiMH screws up the NVD > (negative voltage detection) mechanism used to detect EoC > (end-o-charge), which can easily overcharge a NiMH cell or battery.   My cordless phones use NiMH with no charge control. They get charged or discharged all the time. Last set of cheap cells lasted at least 1500 cycles. So you can do it.     NT

"Steve W." <csr684@NOTyahoo.com>: Jul 15 01:10PM -0400 ralph wrote: >> dash, not the trunk.   > Good Lord! What kind of Luddite is still using a CD in a car?   > Install a unit that will read a USB thumb drive or MP3 player.   That can be a very interesting thing in many newer vehicles that use the factory stereo for a lot more than music. Many are part of the security system, the memory options are stored in it, then if you have the ones where it is an all in one with the HVAC, navigation and more....   -- Steve W.

Wade Garrett <wade@cooler.net>: Jul 15 06:19PM -0400 On 7/15/17 9:44 AM, ralph wrote: >> dash, not the trunk.   > Good Lord! What kind of Luddite is still using a CD in a car?   > Install a unit that will read a USB thumb drive or MP3 player.   Someone driving a fully depreciated 17 year old vehicle who doesn't want to spend a lot of money on a new audio device, not to mention a lot to get it installed if he's not handy...   -- Don't cling to a mistake just because you spent a lot of time or money making it.

micky <NONONOmisc07@bigfoot.com>: Jul 15 06:45PM -0400 In rec.autos.tech, on Sat, 15 Jul 2017 09:44:42 -0400, ralph   >> I have a 2000 Toyota Solara with a factory AM-FM-CD changer, all in the >> dash, not the trunk.   >Good Lord! What kind of Luddite is still using a CD in a car?   It's really amazing how many people on Usenet are willing to be insulting. I wonder if they are like that in their personal lives.   You're also a very sloppy reader or you'd know that's the car I'm selling.   >Install a unit that will read a USB thumb drive or MP3 player.   There are good reasons not to do either of these things, but I'm not going to bother telling you. You may not be a luddite but I don't think you want to learn anything either.

Reverend Harry Hardwick <the.rev@godly.www>: Jul 15 07:36PM -0400 On 7/15/2017 6:45 PM, micky wrote: > There are good reasons not to do either of these things, but I'm not > going to bother telling you. You may not be a luddite but I don't think > you want to learn anything either.     The target audience to buy your used car is a half-broke teenager. They'll want a car with a USB port on the stereo.   If you wanna sell your car, put one in. Get it yet, Gramps?

Reverend Harry Hardwick <the.rev@godly.www>: Jul 15 07:38PM -0400 On 7/15/2017 6:45 PM, micky wrote: > There are good reasons not to do either of these things, but I'm not > going to bother telling you. You may not be a luddite but I don't think > you want to learn anything either.     The target audience to buy your used car is a half-broke teenager. They'll want a car with a USB port on the stereo.   If you wanna sell your car, put one in. Get it yet, Gramps?

Dan Espen <dan1espen@gmail.com>: Jul 15 09:13PM -0400 >> dash, not the trunk.   > Good Lord! What kind of Luddite is still using a CD in a car?   > Install a unit that will read a USB thumb drive or MP3 player.   I'm still using a CD and it works perfectly for me.   My CD player happens to support Data format CDs with MP3s. Each CD holds 250 tracks. With a few CDs I've got a LOT of music in that car and at 250 tracks per, I don't need a changer.   -- Dan Espen

Ed Pawlowski <esp@snet.net>: Jul 15 09:49PM -0400 On 7/15/2017 7:36 PM, Reverend Harry Hardwick wrote:   > The target audience to buy your used car is a half-broke teenager. > They'll want a car with a USB port on the stereo.   > If you wanna sell your car, put one in. Get it yet, Gramps?   Sure, put a $200 radio in it and get $50 more for the car. Let the kid put in his own music of choice.

Ed Pawlowski <esp@snet.net>: Jul 15 09:53PM -0400 On 7/15/2017 9:13 PM, Dan Espen wrote:     > My CD player happens to support Data format CDs with MP3s. > Each CD holds 250 tracks. With a few CDs I've got a LOT of music > in that car and at 250 tracks per, I don't need a changer.   My car takes CD USB and Bluetooth. Fact is, with SiriusXM I've not used any of them for a couple of years. I should put the MP3 CD from my last car in this one though. I've not gotten arount to it in 21 months.

oldschool@tubes.com: Jul 15 03:30PM -0400 The reason so many people are shot on TV is because a black and white TV set has one gun in the CRT and a color set has 3 guns in the CRT. It's those guns that cause all the shootings on TV, particularly when you watch the old Western's and the Cop shows.....   Now you know why there is so much violence on TV....... (But there is hope......Removing those guns will stop all this TV violence permanently)..... <LOL>.

John Robertson <spam@flippers.com>: Jul 15 10:22AM -0700 >> I suspect now that one of the vertical potentiometers is damaged.....   >> John :-#)#   > the vert pot is open. schematic shows a 500ohm B pot. what is the b for. two of the pots have the b suffix. google had conflicting info that its a log pot, but testing the good one with a dvm, it looks linear( i need a battery for my analog meter) . thanks   Cute, will try to remember damaged pots for the future. Always look for the simple stuff first - usually my rule, but hey, who expects broken pots?   And, of course, I should.   John :-#(#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3 (604)872-5757 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

"Ian Field" <gangprobing.alien1@virginmedia.com>: Jul 15 08:29PM +0100 "John Robertson" <spam@flippers.com> wrote in message news:1sSdnRg-g4_B0vfEnZ2dnUU7-f-dnZ2d@giganews.com...   > Cute, will try to remember damaged pots for the future. Always look for > the simple stuff first - usually my rule, but hey, who expects broken > pots?   Pots became extinct just before CRTs. Now all the settings are on EEPROM.

Chuck <ch@dejanews.net>: Jul 15 02:57PM -0500 On Sat, 15 Jul 2017 10:22:36 -0700, John Robertson <spam@flippers.com> wrote:   >the simple stuff first - usually my rule, but hey, who expects broken pots?   >And, of course, I should.   >John :-#(#   Another vertical pot problem I have seen is leakage between the potentiometer and a grounded case.   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

"Ian Field" <gangprobing.alien1@virginmedia.com>: Jul 15 09:05PM +0100 "Chuck" <ch@dejanews.net> wrote in message news:qpskmcdlop3fnpjg50nfdgvkt1vhdhoe48@4ax.com...   >>John :-#(#   > Another vertical pot problem I have seen is leakage between the > potentiometer and a grounded case.   The one I've seen most of is loose rotor and flaky contact between wiper and track.

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