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"pfjw@aol.com" <pfjw@aol.com>: May 16 04:58AM -0700 > ** It is not possible to "lubricate" a sealed pot, you need to make a small hole in it first. Sealing a pot does not prevent it becoming noisy.   There are two basic ways to do this, and one semi-exotic way, the last being universally successful, but with lots of caveats. All but the first require removing the pot from the device.   a) A pressure pump - this will drive the lubricant down the shaft. A threaded tube connects to the pot with an internal sealing O-ring. It is then pressurized with the lubricant inside. In 80% of pots - including the likes of Revox - this works fine. I keep just such a device.   b) Removing the pot(s), warming it (warm, not hot) and dropping it in cold lubricant. The cooling action creates a vacuum and draws the lubricant into the pot. Works in about 75% of those pots that do not respond to the first method. Getting to 95%.   c) Using a small vacuum pump, create a moderate low pressure around the pot, while it is immersed in the lubricant. This will draw air out of the inside of the pot, which when the vacuum is release, will force lubricant into the void. For some hobbyists, especially those who do castings, this will be easy. For others, not so much. And caution is required as too much of a vacuum will entirely fill the inside of the pot. At which point, the process is repeated with the pot 'dry'. This will remove most of what is inside the pot.   Few things are "not possible", with care and attention.   Peter Wieck Melrose Park, PA

Phil Allison <pallison49@gmail.com>: May 16 06:21AM -0700 > > a small hole in it first. Sealing a pot does not prevent it becoming > > noisy.   > There are two basic ways to do this,       ** FFS you trumpet blowing, bullshitting IDIOT !!!   Drilling a 2m hole take only seconds.   A squirt of WD40 takes even less.   Take your stupid, OTT public waking a shove it.           ..... Phil

ohger1s@gmail.com: May 16 07:08AM -0700 On Tuesday, May 16, 2017 at 9:21:08 AM UTC-4, Phil Allison wrote:       Evil Phil said:   > ** FFS you trumpet blowing, bullshitting IDIOT !!!     Reasonable Phil said:   >Drilling a 2m hole take only seconds. A squirt of WD40 takes even less.     Evil Phil said:   > Take your stupid, OTT public waking a shove it.   John says:   Some pots are held together with the four folded over tabs, and bending them up with a slight pry will allow access with a flattened spray straw. This will allow me to spooze the crevice but good with my favorite lubricant (I should write for Penthouse Forum.... ) Bend the tabs back tight and all is well.   Other than that, yeah, a small drill does fine and a dab of RTV will cover the hole nicely.   Either method take very little time.

"pfjw@aol.com" <pfjw@aol.com>: May 16 07:40AM -0700 > Some pots are held together with the four folded over tabs, and bending them up with a slight pry will allow access with a flattened spray straw. This will allow me to spooze the crevice but good with my favorite lubricant (I should write for Penthouse Forum.... ) Bend the tabs back tight and all is well.   > Other than that, yeah, a small drill does fine and a dab of RTV will cover the hole nicely.   > Either method take very little time.   So, tell me, without removing the pot from the device, even with a good vacuum cleaner, would _YOU_ wish to use a drill and possibly let metal shavings into something? Or would you prefer to leave a pot in place and lubricate it with a rather simple tool that covers roughly 80% of applications?   And, if the pot is coming out anyway, why drill it if there are simple alternatives?   Worst of all, even if using a brass-bit, what about getting some shavings into the pot? Don't tell me that has never happened??   "First, do no harm". Applies here as well as anywhere else.   Peter Wieck Melrose Park, PA

"pfjw@aol.com" <pfjw@aol.com>: May 16 07:40AM -0700 On Tuesday, May 16, 2017 at 9:21:08 AM UTC-4, Phil Allison wrote:   > ..... Phil   What happened to "NOT POSSIBLE"?   Peter Wieck Melrose Park, PA

ohger1s@gmail.com: May 16 08:03AM -0700 On Tuesday, May 16, 2017 at 10:40:02 AM UTC-4, pf...@aol.com wrote: Or would you prefer to leave a pot in place and lubricate it with a rather simple tool that covers roughly 80% of applications?   What about the other 20%? Not only does old man Murphy know me on a first name basis, I believe he's related to my wife..   > And, if the pot is coming out anyway, why drill it if there are simple alternatives?   Simple if you have the tool. If I had the tool you use in hand, yes I'd use it. I don't have one. 99.926 percent of the electronics I repair haven't had physical pots installed in them in two decades, so it's not a tool I need. Recurring problems motivate me to seek easier solutions.   Also, one doesn't necessarily have to remove a pot to drill it if necessary. And again, on the small percentage of pots that actually have no open access, bending the fold tabs back gives me the access I need. Not only can I flush it but good with the pot opened, but it gives me enough access to add some viscous silicone slime if I want to restore that slick feel. It takes less time to bend tabs back than it does to pull a vacuum on it, and I don't have to unsolder it.   > Worst of all, even if using a brass-bit, what about getting some shavings into the pot? Don't tell me that has never happened??   Never happened...

John Robertson <spam@flippers.com>: May 15 04:54PM -0700 On 2017/05/15 4:15 PM, Jeff Liebermann wrote: > squirt just before a wrench is applied."   > At this time, nobody seems to have found a copy of the original > article or know the real ingredients.   You have mail!   John :-#)#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 (604)872-5757 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

Ralph Mowery <rmowery28146@earthlink.net>: May 15 07:55PM -0400 In article <ofddbs$s4$1@gioia.aioe.org>, jdangus@att.net says... > Usenet bullshit story that has taken on a life of it's own.   > Kroil works and using WD-40 is about as useful as pissing > on it.   When I was working I used Kroil by the case. Well, probably averaged 3 or 4 cans a week. Works well for many things. I have even used it on some 150 watt mercury vapor lights. They almost unscrew theirselves.   I use something called Ed's Red, a mix of ATF, Acetone, stotards solvent, and kerosene. It is a cleaner for guns that works well. One of these days I am going to have to give it a try for rusted bolts to compair it with the Kroil.

Jeff Liebermann <jeffl@cruzio.com>: May 15 05:52PM -0700 On Mon, 15 May 2017 18:24:41 -0500, Foxs Mercantile <jdangus@att.net> wrote:   >> original article or know the real ingredients.   >So, in other words, this has all the markings of a typical >Usenet bullshit story that has taken on a life of it's own.   Yep, that's about it. After excavating some of the history, it appears to me that the original source, ingredients, test results, and anecdotal testimonials have all changed over the last 10 years and cannot be relied upon to be accurate.   BTW: The acetone + ATF mix is the basis of Ed's Red bore cleaner for your home artillery: <http://handloads.com/articles/default.asp?id=9>   >Kroil works and using WD-40 is about as useful as pissing >on it.   Everything works if you also use a large hammer.     -- 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

"pfjw@aol.com" <pfjw@aol.com>: May 16 09:10AM -0700 > ahno, the switch has an LED lighting when the switch circuit routes power from supply to powered unit. Switch feeds power to ground and thru the LED.   Are you sure you mean this? That much current through an LED would destroy it in short order. In parallel to the current path, perhaps. But not in series.   Peter Wieck Melrose Park, PA

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: May 16 04:54PM +1000 > The non-polarized (NP) caps that are used in speaker crossovers are NP, > but they appear to be electrolytics.   **Some are, some aren't. Electros are pretty easy to pick.     Are they actually electrolytics, > and if so, how do they make them non-polarized compared to standard > electrolytic caps?   **Do a web search. You should be able to locate the method of construction.     > Also, what is the reason they are NP, rather than use regular polarized > caps?   **They must deal with an AC signal, rather than one with DC polarisation. Therefore, they must be non-polar types.     -- Trevor Wilson www.rageaudio.com.au

Phil Allison <pallison49@gmail.com>: May 16 12:06AM -0700 olds...@tubes.com wrote:   -------------------------     > but they appear to be electrolytics. Are they actually electrolytics, > and if so, how do they make them non-polarized compared to standard > electrolytic caps?   ** Different manufacturing process that effectively crates two electros in series with opposite polarities.     > Also, what is the reason they are NP, rather than use regular polarized > caps?   ** Polarised electros conduct when reversed by few volts, so AC current flow is different in each half cycle. Plus the caps get hot.   .... Phil

jurb6006@gmail.com: May 16 12:35AM -0700 In high end speaker they are not always electolytics. They could be but there are some different types. You can look them over at Simplyspeakers and a few other places.   Anything other that a lytic of some of those ratings will be quite expensive, so unless you got really good ears forget it. One technique is to put a smaller cap like a poly or something across it, but then you have to recalculate the value. Easy to do, just subtract what you add.

jurb6006@gmail.com: May 16 12:36AM -0700 >"** Different manufacturing process that effectively crates two electros in series with opposite polarities. "   Isn't it that they have a plate between the two plates ?

gregz <zekor@comcast.net>: May 16 08:17AM > expensive, so unless you got really good ears forget it. One technique is > to put a smaller cap like a poly or something across it, but then you > have to recalculate the value. Easy to do, just subtract what you add.   The non electrolytics have more lifetime. In a system, retrofitting with "better caps" can result in improper repsponse from what a speaker was voiced at. Add resistance and possibly loss, and you have an electrolytic. As far as tolerance, they are pretty accurate, and often tested before installation. Normal electrolytics have given tolerances and can vary with temperature, including varying ESR.   Greg

Phil Allison <pallison49@gmail.com>: May 16 02:24AM -0700 GS wrote:   ----------     > The non electrolytics have more lifetime.   ** Longer than the speaker can possibly last.     > In a system, retrofitting with > "better caps" can result in improper repsponse from what a speaker was > voiced at.   ** Gobbledegook.       > Add resistance and possibly loss, and you have an electrolytic.     ** Plus add THD and IM.   The C value is voltage dependant, di-electric losses are large and di-electric absorption massive - none of which is true of film caps.   Non-polar electros are an economy measure fro mass market speakers.   If used in high power professional speaker, they generally explode in short order.       .... Phil

"pfjw@aol.com" <pfjw@aol.com>: May 16 05:26AM -0700 OK - some basics:   a) very nearly every speaker capacitor is non-polarized. Why? They are designed to work in an AC (alternating current) environment, albeit at rather low voltages.   b) as capacity increases, the cost of a non-electrolytic increases significantly per uF, far more than with an electrolytic cap.   c) non-electrolytics tend to be larger than electrolytics as uF increases.   d) manufacturers, therefore, favor electrolytics as a means to lower costs and lower real-estate requirements.   Those are the most basic reasons that you will see electrolytic capacitors in speaker crossovers. "Voicing" while a very real concern will not be materially affected by changing out one electrolytic for another as the tolerances are pretty sloppy as compared to non-electrolytic capacitors, and even low-end manufacturers would do some basic screening. However, if you choose to substitute a large film cap(s) for an electrolytic, some experimentation may be required as these days, the tolerances for film caps are commonly less than 2%. As compared to as much as +50% for electrolytics.   http://www.updatemydynaco.com/pictures/DynacoA25CrossoverAnnotated.JPG   This is a crossover from a Dynaco A25 speaker. Well respected speaker with excellent drivers, but from a manufacturer that pretty much did everything in the cheapest possible way. One electrolytic cap, and a bunch of sand resistors.   http://www.classicspeakerpages.net/IP.Board/uploads/monthly_2016_09/57cf896d9937f_AR4xxo.jpg.3825ebd29785aceb6ff415ce4b6b4d7b.jpg   This is a crossover from an AR4x speaker, contemporary to the A25, and also well respected. But from a manufacturer that did not do things in the cheapest possible way. Note the inductor, and non-electrolytic cap.   There are many ways to get there.   Peter Wieck Melrose Park, PA

Phil Allison <pallison49@gmail.com>: May 16 06:17AM -0700 pf...@aol.com wrote:   ------------------     > This is a crossover from an AR4x speaker, contemporary to the A25, and > also well respected. But from a manufacturer that did not do things > in the cheapest possible way. Note the inductor, and non-electrolytic cap.   ** AR normally built their speakers in the CHEAPEST way possible.   That white cap in you pic is clearly non original - see pic of original AR4x crossover over.   http://www.classicspeakerpages.net/IP.Board/uploads/monthly_2016_05/5727778baacda_AR-4xax-owithpot.jpg.e5d655c03ff2feab863aa7f426315401.jpg   AR normally used non-polar electros OR paper and oil caps that self destructed.   I bought a pair of AR2Ax 3-way speakers a few years ago just for the cabinets - nothing else was worth keeping.     .... Phil     .... Phil     .... Phil

tabbypurr@gmail.com: May 16 07:01AM -0700 > Those are the most basic reasons that you will see electrolytic capacitors in speaker crossovers. "Voicing" while a very real concern will not be materially affected by changing out one electrolytic for another as the tolerances are pretty sloppy as compared to non-electrolytic capacitors, and even low-end manufacturers would do some basic screening. However, if you choose to substitute a large film cap(s) for an electrolytic, some experimentation may be required as these days, the tolerances for film caps are commonly less than 2%. As compared to as much as +50% for electrolytics.   > http://www.updatemydynaco.com/pictures/DynacoA25CrossoverAnnotated.JPG   > This is a crossover from a Dynaco A25 speaker. Well respected speaker with excellent drivers, but from a manufacturer that pretty much did everything in the cheapest possible way. One electrolytic cap, and a bunch of sand resistors.   They could have been cheaper by using resistance wire.       > There are many ways to get there.   > Peter Wieck > Melrose Park, PA     NT

"pfjw@aol.com" <pfjw@aol.com>: May 16 07:23AM -0700 AR made the 4X for very nearly Fifteen (15) years. Well over 300,000 were made.   What you are showing is a *VERY* early version from the late 60s. AR started with the Chicago-made box caps early on. For a reason so obvious, even you should be able to figure it out?   Later versions used many other different caps. What is in mine is what is very close to what is shown in my link, not Zen, however, but black, similar to a Solen with whitish ends. I purchased them in 1975, new in the box.   You keep reasoning from the specific to the general. Not only is that silly, but that is why you are so often embarrassingly wrong over incredibly simple stuff.   Peter Wieck Melrose Park, PA

"pfjw@aol.com" <pfjw@aol.com>: May 16 07:31AM -0700 > They could have been cheaper by using resistance wire.   Then the warranty calls would have been massive. Keep in mind that in those days, warranties for speakers covered shipping - and manufacturers also shipped packing if necessary.   Raw resistance wire in that application would be a recipe for disaster.   Peter Wieck Melrose Park, PA

tabbypurr@gmail.com: May 16 07:45AM -0700 > Raw resistance wire in that application would be a recipe for disaster.   > Peter Wieck > Melrose Park, PA   What failure mode are you proposing?     NT

"pfjw@aol.com" <pfjw@aol.com>: May 16 08:00AM -0700 > What failure mode are you proposing?   Pick one:   a) Overheating. b) Corrosion at the solder/crimp joints. Nichrome does not solder well. c) Mechanical damage or/due to poor connections. Those materials introduce a 'technique' issue that inevitably leads to failures. d) Excessive variability between speakers. Resistors are a manufactured item that can be used without much thought. Each piece of nichrome would have to be measured and cut - by someone. And then, not mixed up one-to-another as they would be difficult to label individually.   These speakers did undertake a sea voyage from Denmark to wherever, so damp salty air would be a passing thought as well.   Peter Wieck Melrose Park, PA

oldschool@tubes.com: May 16 02:35AM -0400 >the CD played perfectly, at the end the audio was totally inaudible. It was >not a time thing, you could skip to the end of the CD and it would >immediately be bad, skip to the beginning and it was fine.   I had a cheap CD player (boombox) that only played the first 3 or 4 songs on any CD. It was not worth sticking money or time into it. I put it in the barn for a barn radio (the radio worked fine). And bought another CD player.   I think the OP was talking about the CD itself making noise, not the sound from the speakers. He said it's classical music. If it was rock music, he probably would not even hear that noise. But I do wonder if the center hole is not exactly centered. I'm sure that could happen....

"J.B. Wood" <arl_123234@hotmail.com>: May 16 06:27AM -0400 > sound from the speakers. He said it's classical music. If it was rock > music, he probably would not even hear that noise. But I do wonder if > the center hole is not exactly centered. I'm sure that could happen....   Hello, and thanks to all who responded. I took a closer look at that problem CD and indeed the center hole is off center. Not much but ostensibly enough to elicit the observed effect in the CD player. Sincerely, -- J. B. Wood e-mail: arl_123234@hotmail.com

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