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KenO <kenitholson@yahoo.com>: Feb 19 09:17AM -0800 Terry,   "Your initial post said alkaline batteries" Agree, only when questioned found out unfortunately the person I received the electronic device from does not remember if the batteries were zinc/carbon or alkaline.

KenO <kenitholson@yahoo.com>: Feb 19 09:22AM -0800 Jeff,   "Simple really. Alkaline batteries leave what looks like white fuzzy crystals. Some times with bluish green tint.   Zinc Carbon batteries leave what looks like rusty brown sludge. That is also spread about more and not confined to just the terminals."   Thanks for the clarification.   closer to 2nd Zinc Carbon   Any way it can attach a color photo? If yes please tell max size (will try to keep as small as possible).

KenO <kenitholson@yahoo.com>: Feb 19 09:25AM -0800 Jeff Liebermann,   "consider replacing the alkaline cells with rechargeable NiMH LSD (low self discharge) cells such as Eneloop. These types of cells can also leak, but in my experience much less often." Agree have never had problems with either NiCd or NiMH.

John Robertson <spam@flippers.com>: Feb 19 09:46AM -0800 On 2018/02/19 8:08 AM, Fox's Mercantile wrote: > crystals. Some times with bluish green tint.   > Zinc Carbon batteries leave what looks like rusty brown sludge. That is > also spread about more and not confined to just the terminals.   You could test a small portion of the corrosion crystals with a drop of vinegar - if it fizzes then it is alkaline. For certainly test another bit with a drop of backing soda dissolved in water, this time it shouldn't fizz if the vinegar did.   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."

John Robertson <spam@flippers.com>: Feb 19 09:56AM -0800 On 2018/02/19 7:52 AM, KenO wrote: > https://www.bobvila.com/articles/how-to-clean-battery-corrosion/ > http://www.radioworld.com/columns-and-views/0004/vinegar-is-your friend/323304   > John and Reinhard do you have any references for your recommendations?   I'm afraid my information was in a telephone conversation back in the early 90s when I was investigating the best way to deal with ni-cad and other alkaline battery corrosion and called a number of battery companies (this was prior to the Internet). The advice given has been tested subsequently on countless pinball and video game MPU boards by many people and the results are positive. I wrote several articles in our industry trade magazines to get the word out, and have subsequently posted on my web site more info.   http://www.flippers.com/battery.html   First posted in 1997:   https://web.archive.org/web/19970412183538/www.flippers.com/battery.htm (added the 'l' to 'htm' in 1998)   It doesn't always work, the corrosion can be too extensive for economical repairs, but boards that have been treated as advised have rarely failed if they worked after cleaning (and corroded IC sockets, etc. replaced). Boards where traces are missing are normally too far gone, but have been saved with extensive repairs.   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."

John Robertson <spam@flippers.com>: Feb 19 09:58AM -0800 On 2018/02/19 9:25 AM, KenO wrote: > Jeff Liebermann,   > "consider replacing the alkaline cells with rechargeable NiMH LSD (low self discharge) cells such as Eneloop. These types of cells can also leak, but in my experience much less often." Agree have never had problems with either NiCd or NiMH.   What is the memory device? Some sort of CMOS RAM? Most are available in NVRAM these days...   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."

John-Del <ohger1s@gmail.com>: Feb 19 10:35AM -0800 On Monday, February 19, 2018 at 11:00:34 AM UTC-5, KenO wrote:   > "The first thing to try when removing battery snot is plain old water. If the plating is gone, you'll either have to replate or replace the contacts for reliable contact"   > I hope the plating is OK   > Will plain water cause additional damage if the plating is damaged?   If the plating is damaged, the water will cause rust, but that's the least of your problems. Water will quickly and cleanly dissolve the crud, but if the plating is gone, then you can try sanding the base metal clean and apply a blob of dielectric grease between the battery and the contact to seal the connection if you don't want to spend any more effort on it.

Jeff Liebermann <jeffl@cruzio.com>: Feb 19 10:37AM -0800 On Mon, 19 Feb 2018 09:56:55 -0800, John Robertson <spam@flippers.com> wrote:   >rarely failed if they worked after cleaning (and corroded IC sockets, >etc. replaced). Boards where traces are missing are normally too far >gone, but have been saved with extensive repairs.   You're doing better at repairing corrosion damage than me. The problem is that the corrosive fluid tend to narrow the trace width of traces that are still making a connection. Add a little current through the trace, and you have a fuse. Also, the electrolyte acts like, well... and electrolyte. Two parallel traces, separated by a hygroscopic PCB, with a DC voltage across the gap, is going to slowly erode one trace, while building up the other. The net result is that it works for a while, and then craps out again.   I just had both of these effects happen while trying to fix a Rayovac LED head lamp. I think it was this model: <https://www.walmart.com/ip/Rayovac-Virtually-Indestructible-3-AAA-Industrial-Grade-LED-Headlight/53982706> It's quite a decent head lamp, at a good price, and is rate to be water resistant up to IPX4 (splashing water). However, there's no protection against the alkaline batteries leaking all over the PCB. I gave up after it came back the 4th time with essentially the same problem.   The damaged PCB is in my "to be recycled" bin. I can take a photo and post it if anyone wants to see the mess.     -- 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>: Feb 19 10:45AM -0800 On Mon, 19 Feb 2018 09:25:30 -0800 (PST), KenO <kenitholson@yahoo.com> wrote:   > Agree have never had problems with either NiCd or NiMH.   I beg to differ. I have had NiCd and NiMH cells leak. The difference is that unlike alkaline, they don't leak in the package: <http://www.learnbydestroying.com/jeffl/crud/Kirkland-AAA-leak.jpg> I've found from dealing with commercial walkie-talkie batteries, that if I leave the packs totally discharged for more than a few weeks, the batteries will leak. The good news is that this rarely happens.   -- 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

John-Del <ohger1s@gmail.com>: Feb 19 10:54AM -0800 On Monday, February 19, 2018 at 1:37:53 PM UTC-5, Jeff Liebermann wrote: > >etc. replaced). Boards where traces are missing are normally too far > >gone, but have been saved with extensive repairs.   > You're doing better at repairing corrosion damage than me.   Depends on what you're dealing with. $20 electronics deserve no effort unless it's for the satisfaction. But like John, I've repaired extensive PC damage where the board is unavailable or stupidly expensive. Back in the projection TV heyday, I used to do tons of Mitsubishis that suffered coolant leaks onto double side plated through hole circuits both for myself and other dealers that wouldn't attempt it. I bought a stereo microscope to help identify missing/damaged traces and damaged plated through holes. The TVs were several thousand dollars to replace and the boards were several hundred dollars when they were available. Even so, changing the main boards on Mitsus meant a total realignment afterwards.   You do what you have to do.

Reinhard Zwirner <reinhard.zwirner@t-online.de>: Feb 20 12:06AM +0100 KenO schrieb:   [...] > John and Reinhard do you have any references for your recommendations?   Own experience (with alkaline battery corrosion) a few hours ago :-( <sigh> ... I have to admit though that my experience is just with the battery contacts and not with PCB corrosion.   HTH   Reinhard

tabbypurr@gmail.com: Feb 19 04:06PM -0800 On Monday, 19 February 2018 16:08:53 UTC, Fox's Mercantile wrote: > crystals. Some times with bluish green tint.   > Zinc Carbon batteries leave what looks like rusty brown sludge. That is > also spread about more and not confined to just the terminals.   NiCd also white     NT

tabbypurr@gmail.com: Feb 19 04:12PM -0800 On Monday, 19 February 2018 18:45:27 UTC, Jeff Liebermann wrote: > I've found from dealing with commercial walkie-talkie batteries, that > if I leave the packs totally discharged for more than a few weeks, the > batteries will leak. The good news is that this rarely happens.   I've had several NiCds & NiMHs leak, but way less often and far less quantity than primary cells. Usually there's no significant damage to the battery holder.     NT

oldschool@tubes.com: Feb 19 06:56PM -0600 On Mon, 19 Feb 2018 09:56:55 -0800, John Robertson <spam@flippers.com> wrote:   >-- >(Please post followups or tech inquiries to the USENET newsgroup) > John's Jukes Ltd.   While reading this thread, several questions keep coming up.   First, why cant the battery makers design batteries that cant leak? I suppose cost is the main reason, but it would seem that there could be a coating of something like silicone rubber or some sort of plastic that could contain any leakage inside the battery's container.   Secondly, I often read on instructions "Do not mix battery types". Meaning dont use both carbon-zinc and alkaline batteries together. I have often questioned the reasoning for that. ??? I am aware that Carbon/zinc batteries produce 1.5V and Alkaline produce 1.2V, so that could be an issue with some electronics, but would probably not matter in a flashlight.   I do sort of wonder if mixing battery types would cause corrosion and leakage between the two dissimilar batteries, the same way connecting copper plumbing pipes to a galv steel pipe does. I've seen the dielectric corrosion occur mostly at the joint between the different pipe materials, which is the first place for a leak to occur. (They do make dielectric unions to isolate the metals),   Then the thought also occurs, what wouyld happen if both types of batteries began to leak at the same time. Would one leaking chemical neutralize the other, or would the two chemicals react and cause a reaction, which may produce dangerous fumes, or create heat, which could result in a fire? (I never studied chemistry, so I really dont know).   Lastly, Has anyone ever come up with a "Battery Pan", meaning an enclosure around the battery compartment that would keep leakage confined to ONLY the battery compartment? If not, why not? In an ideal world, the battery compartment for all electronics would be removable and replacable, with a universal battery holder (for each type of battery). This would also be leak proof. I'm sure this could be done, but once again, we're back to cost. And we live in a disposible world, so I dont forsee this ever happening.

John Robertson <spam@flippers.com>: Feb 19 05:03PM -0800 >> batteries will leak. The good news is that this rarely happens.   > I've had several NiCds & NiMHs leak, but way less often and far less quantity than primary cells. Usually there's no significant damage to the battery holder.   > NT   I've had 100's of NiCad/NiCd batteries leak on our pinball game boards since the 1970s. I stored these leakers for many years in a couple of milk crates (didn't want to simply toss in garbage) until the recycling provided by our city (Vancouver, BC) gave us a new home for them.   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."

oldschool@tubes.com: Feb 19 07:07PM -0600 On Mon, 19 Feb 2018 10:45:21 -0800, Jeff Liebermann <jeffl@cruzio.com> wrote:   >I've found from dealing with commercial walkie-talkie batteries, that >if I leave the packs totally discharged for more than a few weeks, the >batteries will leak. The good news is that this rarely happens.   I have also had some NiCd batteries leak. But that was after years of non-use. In fact I had some brand new ones (still in their package), that got misplaced and years later I found them and they were corroded inside the package. The corrtosion was confined to the package so nothing aside from the batteries was damaged, and I just tossed them in the trash.   QUESTION: What are those coin cells? (like the ones used in computers for the system clock). Has anyone ever seen them leak? I ask because I have several old computers that have been sitting around un-used for years, and I never removed them cells.

oldschool@tubes.com: Feb 19 07:13PM -0600 On Mon, 19 Feb 2018 17:03:30 -0800, John Robertson <spam@flippers.com> wrote:   >since the 1970s. I stored these leakers for many years in a couple of >milk crates (didn't want to simply toss in garbage) until the recycling >provided by our city (Vancouver, BC) gave us a new home for them.   If you trash them, do they emit some sort of dangerous substance? I would prefer to recycle stuff like that, but I've never seen any place that takes small batteries like that. In my area. (Yes, they do recycle car batteries though).

oldschool@tubes.com: Feb 19 07:19PM -0600 On Mon, 19 Feb 2018 17:03:30 -0800, John Robertson <spam@flippers.com> wrote:   >I've had 100's of NiCad/NiCd batteries leak on our pinball game boards >since the 1970s. I stored these leakers for many years in a couple of >milk crates (didn't want to simply toss in garbage) until the recycling   Just curious. It sounds like you repair pinball machines. Aside from playing them when I was a kid, I know little about them. But I did once see one taken apart, and it appeared to be little more than a complicated bunch of relays and lights. And they operated from a wall outlet. I kind of think there was a power transformer inside, so I assume those relays and lights were low voltage. (probably 6 or 12V).   So, why are there batteries inside of them?

John-Del <ohger1s@gmail.com>: Feb 19 07:13PM -0800 > outlet. I kind of think there was a power transformer inside, so I > assume those relays and lights were low voltage. (probably 6 or 12V).   > So, why are there batteries inside of them?     Well yeah, the early electromechanical pins used relays, switches, and solenoids. Scoring was by indexed reels. Starting in the late 70s, they started using electronics for sound and light controls plus digital scoring and play field animation.

Jeff Liebermann <jeffl@cruzio.com>: Feb 19 07:19PM -0800 >QUESTION: What are those coin cells? (like the ones used in computers >for the system clock).   The CR2032 coin cells are solid lithium and not rechargeable. (The MR2032 are rechargeable.   >Has anyone ever seen them leak?   The CR2032 type cell does not contain any liquid electrolyte. There's nothing inside that might leak. <http://802.11junk.com/jeffl/crud/CR2032-disassembled.jpg> The lithium is the clear stuff, which turned white when exposed to air. The black stuff carbon.   >I ask because I >have several old computers that have been sitting around un-used for >years, and I never removed them cells.   The cells are probably dead by now. I have a pile of 10-20 year old motherboards in the closet. The coin cells haven't leaked. The previous generation of batteries leaked all over the PCB.   -- 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

John Robertson <spam@flippers.com>: Feb 19 10:52PM -0800 > outlet. I kind of think there was a power transformer inside, so I > assume those relays and lights were low voltage. (probably 6 or 12V).   > So, why are there batteries inside of them?   Batteries are used to keep book-keeping information - number of games played, number of coins, replay levels, game adjustable features, etc. The most common chip used at first was the 5101 256x4 CMOS RAM, needed roughly 2VDC to maintain and usually a 3.6VDC Ni-Cad battery was installed to keep that device charged.   I didn't toss these batteries as I didn't want to pollute the garbage with them and kept them under my bench in a milk crate (had two crates filled over 20 years - they didn't leak enough to make any sort of mess or odor) and in the last few years recycling got to the point where they would take old batteries at no charge so we could finally safely dispose of them - I assumed safely, but not so sure now that I hear about all the recycling done in 3rd world countries...   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."

oldschool@tubes.com: Feb 20 12:01AM -0600 On Thu, 15 Feb 2018 08:20:58 -0500, Tim Schwartz <tim@bristolnj.com> wrote:   >11). They are the same as in the KT-76 manual, and rather confusing.   >Regards, >Tim   I noticed that. I am starting to make sense out of this tuner. I really think I prefer an old analog tuner though. Simple is better....   Just my opinion, but I think that all companies who sell electronics should have their manuals online. It's just a courtesy thing. Some companies do, but Kenwood is not one of them. I do kind of wonder the legality of websites that charge money for manuals. For example, Kenwood should sue these companies that sell their manuals. But then again, Kenwood dont provide them, so they dont get a gold star from me. Even if they do make some fairly decent electronics.

Jon Elson <elson@pico-systems.com>: Feb 19 11:47PM -0600 philo wrote:   > The guy finally tested it and it did not do the job.   Yes, I used a big halogen lamp MANY years ago, and had VERY long exposure times. A 400 W mercury vapor lamp with the outer glass shield removed did a little better. Then, I finally switched to a different photoresist that was more sensitive, and now use filtered black light tubes and have about 1 minute exposures. (This is for PC board resist, not silk screens, so their emulsions might still need a lot more light.)   Jon

makolber@yahoo.com: Feb 19 02:03PM -0800 > The Envy has such a high air through-put that it doesn't take long to injest > enough dust to start causing problems.   get a piece of foam and make an external intake filter   much easier to clean an external filter   m

"~misfit~" <shaun.at.pukekohe@gmail.com>: Feb 20 04:40PM +1300 > get a piece of foam and make an external intake filter   > much easier to clean an external filter   > m   I thought of that but the air enters in multiple places so that ancilliary hardware gets airflow. Short of sitting it on a full-sized pad of fine-pored open-cell foam that wraps up the front and sides (and supporting that above the desk on a grating-type thing) it's not really an option.   Cheers, -- Shaun.   "Humans will have advanced a long, long way when religious belief has a cozy little classification in the DSM*." David Melville (in r.a.s.f1) (*Diagnostic and Statistical Manual of Mental Disorders)

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