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tabbypurr@gmail.com: Feb 11 10:12AM -0800 > Of course it has to be safe for the circuit board and components too. I > use the 91% isopropyl alcohol, so it evaporates quickly and leaves > little water residue behind. (Then leave it dry well before use).   I did one yesterday, got what I could off some bent flat strip with a screwdriver, got the remainder off with a grinder. A dishwasher is more often the suitable treatment, but as has been said there are some parts definitely not dishwashable. Speakers, unpotted relays, variable caps, paper caps, transformers, some other stuff.     NT

Jeff Liebermann <jeffl@cruzio.com>: Feb 11 10:30AM -0800 >all the years I've worked on electronics, I have never found a perfect >way to clean up leaked batteries. Is there some sort of spray or a >chemical that will dissolve or deactivate that crap?   I use 409 spray cleaner, a plastic scraper, and a paint brush. For alkaline cells, scrape off as much of the white powder as possible. Clean what you can with the small paint brush. Then attack with the 409 spray. It will evaporate dry in about an hour. If you have an air compressor, you can blow out the excess liquid and it will dry quicker.   It's been so long since I've seen any equipment that uses a carbon zinc cell, that I don't recall how it's cleaned. Probably some alkaline cleaner.   The most common problem I see are corroded battery springs and contacts. Once the plating is gone, it's difficult to keep them from corroding again. Grease helps, but makes a mess. So, I replace them with similar or identical spring contacts purchased on eBay and other online vendors: <https://www.ebay.com/sch/i.html?_nkw=battery+spring+contact>     -- 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

Reinhard Zwirner <reinhard.zwirner@t-online.de>: Feb 11 07:35PM +0100 Ralph Mowery schrieb:   [...] > As most of the batteries used in portable devices are some type of > alkaline the baking soda is the opposit of what should be used. White > vinegar is what you should be using to neutralize it.   Full ack!   Regards   Reinhard

Look165 <look165@numericable.fr>: Feb 11 08:35PM +0100 Since this layer is alcaline, the best to use an acid ; vinegar for instance.

"pfjw@aol.com" <pfjw@aol.com>: Feb 11 11:41AM -0800 On Sunday, February 11, 2018 at 10:23:41 AM UTC-5, Ralph Mowery wrote:   > been a from of acid. I know the car batteries use acid and the baking > soda is good for that. Just not good for the newer smaller AA,C,D type > batteries.   LeClanche cells are acid-based (Ammonium CLoride) with an acidic pH (depending on the age of the cell) from about 6 (nearly dead) to about 4.6 (fresh). Hence the pointer to baking soda.   Baking Soda (Sodium Bicarbonate) is about pH 8.4 when dissolved in water. Household vinegar is pH 2.4, and will tear copper apart.   The neutralizing agent wants to be slow and mild. Vinegar (acetic acid) is pretty strong.   Peter Wieck Melrose Park, PA

Jeff Liebermann <jeffl@cruzio.com>: Feb 11 02:35PM -0800 On Sun, 11 Feb 2018 20:35:56 +0100, Look165 <look165@numericable.fr> wrote:   >Since this layer is alcaline, the best to use an acid ; vinegar for >instance.   <https://en.wikipedia.org/wiki/Alkaline_battery#Leaks> Yep. The white stuff from an alkaline cell is potassium carbonate and has a pH of about 11 in water: <https://en.wikipedia.org/wiki/Potassium_carbonate> Vinegar works, but citric acid (lemon juice) smells better. If the cleaner produces gas bubbles, it's working. However, I don't think it matters much. I use 409 household cleaner which has a pH of 9 to 11.5 depending on concentration: <http://www.gjfood.com/pdf/msds/79_820040.pdf> It produces some bubbles, does a good job of cleaning, and smells ok.   The white stuff that leaks out of carbon zinc battery is the zinc chloride electrolyte: <https://en.wikipedia.org/wiki/Zinc%E2%80%93carbon_battery#Durability> <https://en.wikipedia.org/wiki/Zinc_chloride> Zinc chloride in water is very acidic with a pH of 2.0 to 3.0 depending on concentration. It's very soluble in water so any water based alkaline cleaner, such as houshold ammonia, should work.       -- 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 11 02:38PM -0800 On Sun, 11 Feb 2018 14:35:43 -0800, Jeff Liebermann <jeffl@cruzio.com> wrote:   >The white stuff that leaks out of carbon zinc battery is the zinc >chloride electrolyte:   Oops. Zinc chloride is the crud that leaks out of the battery. The electrolyte is ammonium chloride.   -- 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

oldschool@tubes.com: Feb 11 05:27PM -0600 On Sun, 11 Feb 2018 04:51:20 -0800 (PST), "pfjw@aol.com" <pfjw@aol.com> wrote:   >a very strong concentration of baking soda mixed into distilled water.   This makes sense, but I have to ask why regular tap water wont work V/S distilled water? I know that adding water to a car battery should be distilled, (so it dont have any minerals), but in this case, it would seem that any clean water would work.   But maybe I am missing something. Yet, I do try to eliminate unnecessary expenses, and distilled water adds to the cost, not to mention an extra trip to a store, since it's not something I keep on hand.

Jeroen Belleman <jeroen@nospam.please>: Feb 12 12:31AM +0100 On 11/02/18 23:38, Jeff Liebermann wrote: >> chloride electrolyte:   > Oops. Zinc chloride is the crud that leaks out of the battery. The > electrolyte is ammonium chloride.   Zinc chloride actually attracts so much water that it dissolves in it, as I found out when I tried to crystallize the stuff.   Jeroen Belleman

Jeff Liebermann <jeffl@cruzio.com>: Feb 11 05:41PM -0800 On Mon, 12 Feb 2018 00:31:54 +0100, Jeroen Belleman   >Zinc chloride actually attracts so much water that it dissolves in it, >as I found out when I tried to crystallize the stuff.   >Jeroen Belleman   What were you trying to make? Soldering flux (usually a mix of zinc chloride and hydrochloric acid)? Don't use it on electronics as it's conductive.   -- 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

Jeroen Belleman <jeroen@nospam.please>: Feb 12 09:17AM +0100 Jeff Liebermann wrote:   > What were you trying to make? Soldering flux (usually a mix of zinc > chloride and hydrochloric acid)? Don't use it on electronics as it's > conductive.   Nah! Just part of a high school chemistry course 45 years ago.   Jeroen Belleman

Mike Coon <gravity@mjcoon.plus.com>: Feb 12 08:38AM In article <buj18dliqogl4bpp8ghke6v6b5psm86f6r@4ax.com>, oldschool@tubes.com says...   > But maybe I am missing something. Yet, I do try to eliminate unnecessary > expenses, and distilled water adds to the cost, not to mention an extra > trip to a store, since it's not something I keep on hand.   What do you put in your steam iron? That's where most of my distilled/de-ionised water goes...   Mike.

oldschool@tubes.com: Feb 12 04:34AM -0600 On Mon, 12 Feb 2018 08:38:22 -0000, Mike Coon <gravity@mjcoon.plus.com> wrote:     >What do you put in your steam iron? That's where most of my >distilled/de-ionised water goes...   >Mike.   Steam iron? Do they still use those things? I recall my mother using one in the 1950s and 60s....   Either way. blue jeans and flannels shirts dont need ironing... That's about all of us rural folks wear, aside from our camo hunting clothes.   I did once hear of a guy trying to iron his birthday suit, after drinking a lot of shine.... Luckily his wife ironed his head with a cast iron frying pan before he damaged too much of his birthday suit. and she then sent him to bed.

jurb6006@gmail.com: Feb 12 02:40AM -0800 >"Back when projection TVs were plagued with coolant leaks, I used to soak the entire circuit board in an ammonia and soap solution. But *first*, everything that can trap water must be removed. Back then, that meant SMPS transformer, HOT and flyback XFRs, inductors,etc. A lot of work but it fixed stubborn symptoms and no call backs. "   I had a different technique. I washed it in hot water, then alcohol, then acetone with a brush and then blew dried it on hot to evaporate everything. And then sprayed with spray solvent to make it cold. That squeezes the shit out of the board, which is quite porous. Repeated about 4 times. The last time left the acetone or alcohol on it, heated it up with the blow dryer and waited a while until you could not smell it anymore.   The worst part was when it corroded the copper traces. Can't solder to them, must get all the way to the point where it is no longer dark and add a jump[er.And also extra clean that area because there is more conductive shit in it. It is actually in the board and you can see bubbles when you heat it.   I remember old AA and AB GE chassis bubbling under the solder on the gripletts which impeded their soldering. And those were about 90 % of the problems with those sets.

oldschool@tubes.com: Feb 12 04:40AM -0600 On Sun, 11 Feb 2018 17:41:13 -0800, Jeff Liebermann <jeffl@cruzio.com> wrote:     >What were you trying to make? Soldering flux (usually a mix of zinc >chloride and hydrochloric acid)? Don't use it on electronics as it's >conductive.   That's acid plumbing solder for copper pipes.   But you brought up a question. Electrical solder is rosin. What exactly is roisn and how does it work for a flux? Is it the same thing used for playing a violin, which as far as I know, is made from pine tree sap?

tabbypurr@gmail.com: Feb 12 03:00AM -0800 > But you brought up a question. Electrical solder is rosin. What exactly > is roisn and how does it work for a flux? Is it the same thing used for > playing a violin, which as far as I know, is made from pine tree sap?   that's what it is. Just take pine resin & heat to drive off the volatiles. You can get 25-50kg resin per tonne of wood pulp, but only from pine. Spruce gives less.     NT

Look165 <look165@numericable.fr>: Feb 12 12:39PM +0100 The older method is the metallic brush and some elbow oil ! It is efficient.

John-Del <ohger1s@gmail.com>: Feb 12 04:37AM -0800 > >"Back when projection TVs were plagued with coolant leaks, I used to soak the entire circuit board in an ammonia and soap solution. But *first*, everything that can trap water must be removed. Back then, that meant SMPS transformer, HOT and flyback XFRs, inductors,etc. A lot of work but it fixed stubborn symptoms and no call backs. "   > I had a different technique. I washed it in hot water, then alcohol, then acetone with a brush and then blew dried it on hot to evaporate everything. And then sprayed with spray solvent to make it cold. That squeezes the shit out of the board, which is quite porous. Repeated about 4 times. The last time left the acetone or alcohol on it, heated it up with the blow dryer and waited a while until you could not smell it anymore.   Seems like a lot more work than a one step soak. We received a bulletin from RCA about coolant leaks, and they suggested ammonia based detergents as the most effective way of removing the coolant and it's associated contamination. I had a PTK195 that would do all sorts of very intermittent weird things in the vertical circuit even after a regular cleaning. I found a product called Parson's Sudsy Ammonia and used that diluted in a parts washer. The board were spotless and even glossy after drying.       > I remember old AA and AB GE chassis bubbling under the solder on the gripletts which impeded their soldering. And those were about 90 % of the problems with those sets.   My brother (the hero) used to hard wire those GEs through the griplets but I used to just solder the bottom, solder the top, then resolder the bottom again and give it a good spay of Flux-Off (the original stuff). That took less time than it might seem and they never came back.

Jeff Liebermann <jeffl@cruzio.com>: Feb 11 10:19AM -0800 >Thanks for the advice Jeff. And the link. I did take this machine >apart once about 5 years ago to replace the hard drive. That all went >fine.   That's a start. However, to reflow the BGA chips on the motherboard, you'll need to remove the motherboard from the plastic case. I take photos as dive into the machine. Seems to impress (or panic) the customer. For example: <http://www.learnbydestroying.com/jeffl/pics/repair/HP%20Envy%20m6%20clogged%20fan/slides/HP%20Envy%20m6%20A10%20CPU.html>   >when I was typing out the original message I realized I didn't have >the model number on hand and knew at the time that I really should >have included it with my post. I always seem to get caught.   That's a catch phrase that I use quite often. An amazing number of people ask questions without supplying much in the way of identifying the device they're trying to repair. If they're stuck on something, they will describe what they've done, but not what problem they're trying to solve. After many years, I suspect the problem is chronic. Here's my magic formula for getting mostly sane answers on forums and newsgroups: 1. What problem are you trying to solve? No history or product reviews, just the problem. 2. What have you done so far and where are you stuck? What happened? 3. What do you have to work with? Maker, model, version, numbers.   This won't work for a laptop, but I've been successfully reflowing HP Jetdirect cards in a toaster oven. So far, 18 working boards out of 20: <http://www.learnbydestroying.com/jeffl/pics/repair/BGA%20reflow/index.html> Also about 15 assorted HP printer PC boards and a few game boards. Protecting plastic parts, that are easily melted, is the main problem. Aluminum foil shields do not work, so I have to remove the parts. Most everything else that can survive PCB soldering, can survive the toaster oven reflow. Unfortunately, there are too many plastic parts on a laptop motherboard, so it's not going to work.       -- 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 11 10:02AM -0800 >> in your ear. Let us know if it reduces the noise level and improves >> the SNR (signal to noise ratio) in this newsgroup.   >Well I'm not an earologist,   That would be an otolaryngologist: <https://en.wikipedia.org/wiki/Otorhinolaryngology> Please add the word to your grammar, vocabulary, and spelling chequer.   >but I presumed more would get on the eardrum if it were sprayed in, >hence the suggestion of sorts. And if some does, it's bound to >reduce noise, to some degree.   It might reduce the high end frequency response of the ear drum, but the sensitivity to audible noise would likely be worse. Water, oil, and presumably Deoxit are incompressible and thus transmitting sounds and noise better than through compressible air. That's why we can hear when submerged in water. Besides, I don't think the ultra expensive Deoxit Pro GX3 is currently available in spray form. Since every drop is valueable, a proper dispenser would be a blunt needle tip bottle, not a brush or swab, and certainly not a wasteful spray.     -- 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 11 09:48AM -0800 On Sun, 11 Feb 2018 02:47:47 -0800 (PST), bruce2bowser@gmail.com wrote:   >> >https://www.washingtonpost.com/news/inspired-life/wp/2018/02/01/this-amateur-astronomer-found-a-satellite-lost-in-space/   >> Sure. When funding runs out, the satellite gets lots.   >Lost, you mean?   Yep. You have found a character transposition typographic error which was not detected by my spelling chequer and was probably due me typing with one hand while eating dinner at the computah desk. Thank you for your concern and attention to detail. The world is now a better place.   Incidentally, terrestrial space junk is valuable: <http://www.pbs.org/wgbh/roadshow/fts/houston_spacejunk.html> ...one "flown" engine bolt that was part of the space shuttle Challenger is worth about $250. If it had never left a launch pad, Gary estimates the same bolt might sell for a more down-to-earth price of $20. This is from 2006.   -- 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

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