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oldschool@tubes.com: Mar 10 04:04AM -0600 On Thu, 9 Mar 2017 20:17:16 -0600, Foxs Mercantile <jdangus@att.net> wrote:   >> the old paper/wax caps in old tube gear?   >Were you NOT paying attention previously when we ALL told >you to use the yellow plastic caps? 630 volt.   I WAS paying attention and I even contacted that seller and found out they are made in China.   ><http://www.tuberadios.com/capacitors/>   >Or are you just being stubborn?   No, not being stubborn , I just dont want caps made in China. Not much of anything made in China is a quality item. That seller has good prices and a fair selection, but I still dont want China caps, which will likely contain duds, and I'll end up replacing all of them in 5 years or less, again.   And that site dont give enough info to translate to other sites. They are just called "Axial Film Capacitors" on that site. When I look at other sites, I see them sold with some sort of "poly" name, and I see the word "film" used, as well as "foil". So, what do these compare to in the words used to sell other brands?   That word "film" bothers me, anyhow. Just what the heck is this film? Is it just some sprayed on metalic particles? The old paper caps contained foil, which to me means something that looks like tin foil used in the kitchen. Maybe I'm wrong, but if my radio or (whatever) was designed for caps made with foil, I'd prefer to use caps with foil, and whatever plastics they used to replace the paper. In other words, I want caps that most closely mimic the original caps, except without the paper.   >replaced. Trying to "just replace the bad ones" is a fool's >errand. They're all bad or will fail after they're "back >in service" again.   Those paper caps may be crap now, but considering many of them lasted 50 years, they were not all crap, to last that long. I doubt any China made caps will last even close to 50 years. I may be wrong, but based on nearly all China products, I doubt any of them will last 5 years. Everything made in China is just throw away short lived junk. Made to fail one day after their warranty expires. >"But it's Collins" and "Those were mil-spec" and and and >every other excuse for not changing them. Changing them made >a profound difference in how well the radio works.   I'm sure it did make a difference to the better, but for how long?   But rather that toss out my opinion, which is based on my overall feelings about China products, you tell me how these caps have worked for you. (assuming they are what you have used). What precentage of them have been duds? If you have tested them, how accurate are they? Have you had any fail? How long have you used them? Will they really handle the max voltage they are rated as? How do they perform under heat and other extremes? DId your Collins work as designed, or did you have to re-align it or do any modifications because the caps are not the "foil" type, and thus are not what the circuit was made to use?   Sellers (of anything), always rate their goods at "Top Quality", but advertising is mostly all lies. I want references from you, and anyone else who is NOT connected to the seller.   >These parts are bad. Anyone that tells you otherwise is >either lying to you or is delusional.   Although this is drifting from the topic, I just bought an old Sencor Substitution box. It's for Resistance, Capacitors, (including lytics), one silicone and one selenium diode, and a few other features. I took a modern VOM with capacitor tester, and found all the paper/wax caps in that box are still very accurate. However some of the lytics are not even close. The resistors are all close too. Considering these parts have seen little voltage and use, I see no reason to change any of the small caps or the resistors. I do plan to change the electrolytics though, because I know they deteriorate just from age, whether they are used or not, because of the chemicals in them. (and my tests confirm they are not even close to their rated UF values, some as much as 50% off.   But I see no reason to change those small caps (.05 .001, etc). Not for the brief times thay are used. and they are all very accurate in their values.

ohger1s@gmail.com: Mar 10 05:01AM -0800 > But I see no reason to change those small caps (.05 .001, etc). Not for > the brief times thay are used. and they are all very accurate in their > values.   I have tons of new old stock caps that I keep for nostalgia reasons (dad's), but if I place them on my LC75 and run working voltages into them, most of them will draw excessive current and never "reform". Most are also wildly (by today's standards) off value. I don't know if they drifted over time or if they're typically that far off when new.   Of all the mistakes you made in your rant, the biggest is confusing Walmart Chinese products with individual components. Unless you have a natural racist bent, be aware that having Chinese DNA does not preclude one from making quality or innovative assemblies or components as needed.   When rebuilding a 50 year old radio, we find many original caps inside. Very few can pass a voltage test, and really, when is the last time these radios were used daily? 30 or more years ago? Most of the old radios you will find to restore haven't been used in decades. Those paper caps were shot long ago even if the circuit still struggles to life with them.

"pfjw@aol.com" <pfjw@aol.com>: Mar 10 05:20AM -0800 A few things:   Today, capacitors are commodities. Meaning that the technology involved in making them is fully established, well understood, extremely reliable and (now) very simple. Meaning, again, that the lowest-cost producer making a generic product will pretty much win the market. Meaning (a third time), that the cost of 'faking' such a device will likely approach or exceed the cost of making the proper product in the first place.   So, those capacitors that require very little technology - small-value film caps, for instance - will be cheap and plentiful. And, apart from very specific requirements - aerospace, medical, ultra-precision and similar - there is no reason to choose one item over another from one source over another as, at that level, they are all pretty much from the same place.   Electrolytics do have a greater variation, include different technologies, different chemistry, materials and such, have many different applications, and sub-categories within those applications. With that in mind, one may choose from different sources.   Specialty caps are a different matter altogether, and unless one is in the Aerospace, medical, ultra-precision or similar industries, not really relevant to vintage equipment. Russian PIO caps presently in vogue with the audio hobby are a case in point. Utterly silly indulgences but plenty of yiches.   Meaning that unless you wish to pay aerospace prices, purchase the item that meets the needs at the best price from a *RELIABLE* supplier. *RELIABLE* supplier will protect you from counterfeits - usually at a very small premium, but well worth it. And if that part happens to be from China, comfort yourself that it is due to the commoditization of the product - and your preferred suppliers simply cannot make a profit in that line. The bottom line is that your vintage item is singing again, far more reliable than it ever was in the past, and, very likely far into the future.   One example: I pay about $1.75 extra per transistor from Mouser than for the same part-number from another supplier. Why? Mouser is a major contributor and founder of anti-counterfeit parts organizations.   https://en.wikipedia.org/wiki/Mouser_Electronics   If Mouser sells me a part, I feel pretty sure it will be as represented, whatever the country of origin. Yes, I tend to hold my nose and grumble, if that is China. But increasingly often, the alternative is nothing at all, or old-stock material no better than what is being replaced.   Does your meter test those caps and resistors at any sort of operating voltage? Before you describe them as 'very accurate', they must be tested at operating voltages.   Peter Wieck Melrose Park, PA

Foxs Mercantile <jdangus@att.net>: Mar 10 07:34AM -0600 > That seller has good prices and a fair selection, but I still > don't want China caps, which will likely contain duds, and > I'll end up replacing all of them in 5 years or less, again.   Ok, how about willfully ignorant or xenophobic.   > whatever plastics they used to replace the paper. In other > words, I want caps that most closely mimic the original caps, > except without the paper.   Which shows a complete and total misunderstanding of what capacitors are.   > Those paper caps may be crap now, but considering many of them > lasted 50 years, they were not all crap, to last that long.   Many? Of the billions that were produced between 1935 and 1965 Almost all of them have failed. The few that "might still be good" are statistically zero.   > doubt any of them will last 5 years. > Everything made in China is just throw away short lived junk. > Made to fail one day after their warranty expires.   More willful ignorance on display.   > overall feelings about China products, you tell me how these > caps have worked for you. (assuming they are what you have > used).   There's that magic word "feelings" again. Based on nothing.   > What percentage of them have been duds? If you have tested > them, how accurate are they? Have you had any fail? How long > have you used them?   I have been using them since 1994 when I got back into vintage radios and test equipment after retiring. 23 years now. I have never had a failure of any of the yellow plastic capacitors.   > Will they really handle the max voltage they are rated as? > How do they perform under heat and other extremes?   Yes and flawlessly.   > Did yourCollins work as designed, or did you have to re-align > it or do any modifications because the caps are not the "foil" > type, and thus are not what the circuit was made to use?   Other than some expected drift due to aging components little or no alignment, other than "touch up" was required. This was done to make the radio "work as specified" not just "it works."   You still completely misunderstand how capacitors work.   > I just bought an old Sencor Substitution box. > I took a modern VOM with capacitor tester, and found all the > paper/wax caps in that box are still very accurate.   That is NOT a comprehensive test. It says nothing about leakage or the probability of failure with applied voltage.   > But I see no reason to change those small caps (.05 .001, etc). > Not for the brief times they are used. and they are all very > accurate in their values.   More willful ignorance to justify your position.   This is like assuming your tires are safe, even though you have to put air in them every time you wish to drive your vehicle.   If you'll pardon the pun, to recap, I've been doing this for 23 years as a source of income. I haven't had ANY radios come back due to failures of the "cheap Chinese crap" capacitors as you insist on calling them.       -- Jeff-1.0 wa6fwi http://www.foxsmercantile.com

Ralph Mowery <rmowery28146@earthlink.net>: Mar 10 10:18AM -0500 In article <a7dd2134-3369-fee3-beed-722ec1c4a3b9@att.net>, jdangus@att.net says...   > This is like assuming your tires are safe, even though you have > to put air in them every time you wish to drive your vehicle.   Speaking of unsafe tires, they do seem to have a limiated lifetime even if not used very much. Friend jsut went through that with a tire company. He had a tire that is starting to seperate. He talked with the tire maker. While the tire had plenty of thread and mileage let on it, it was over 7 years old. The company told him that after abut 5 to 6 years many tires will just go bad. In a way I wish that I had been aware of that a year or two ago. I am retired and do not drive that much and have a car and truck. I put some tires on them that was rated very high in the milage thinking I would not have to worry about tires for a long time, but seems that they may age out with over half the thread left on them.   Speaking of China. They make some items that seem to be as good as any,and they make a lot of junk. I have several pieces of equipmant from China that seems to be as good as any. Friend ordered some transistors and all of them were bad junk that did not even test on a transistor tester.   As many power tubes are not made in the US anymore a company contractes with a China company to make some. They seem to hold up very well.

"Dan" <dlbeam1@comcast.net>: Mar 10 11:31AM -0500 Give this site a try.   https://www.tedss.com/LearnMore/American-Made-Capacitors     <oldschool@tubes.com> wrote in message news:43t3cc9j919psgj3l1jiqerqdcvdd7jo84@4ax.com...

oldschool@tubes.com: Mar 10 04:34AM -0600 >boot (trunk) >gear change (gear shift) >and there are plenty more...   This one gets me.   What we call a Horse Trailer, (or livestock trailer), they call them a FLOAT. That's just plain weird....

Ralph Mowery <rmowery28146@earthlink.net>: Mar 10 10:22AM -0500 In article <3505cc90tvd4n293r9ndfan6d9kjqpd2fj@4ax.com>, oldschool@tubes.com says...   > This one gets me.   > What we call a Horse Trailer, (or livestock trailer), they call them a > FLOAT. That's just plain weird....   At work there was an engineer from England. He wanted a torch in an area that was hard to get to. Two mechanics spent about an hour dragging an acelene and oxygen torch to the area. He asked what that was for and they said it was what he wanted. Found out he really wanted a flashlight. That is called a torch where he came from.

dansabrservices@yahoo.com: Mar 09 07:04PM -0800 Also designed for component insertion machines which can't really handle bare wire.   Dan

Andy Burns <usenet@andyburns.uk>: Mar 10 07:06AM > Also designed for component insertion machines which can't really > handle bare wire.   Can be used as "ID" links to enable/disable features on different runs of a board.

oldschool@tubes.com: Mar 10 03:19AM -0600 On Thu, 9 Mar 2017 19:04:45 -0800 (PST), dansabrservices@yahoo.com wrote:   >Also designed for component insertion machines which can't really handle bare wire.   >Dan   So these things really *DO* exist??? I thought it was either a typo, or the webpage was made up by someone who was clueless about electronics.   That seerms pretty goofy, but I do imagine some machines cant handle the bare wires.....   I'm guessing they are just a piece of solid wire with a "shell" around it.   Now, assuming they use a color code on them, what would it be? I thought it would be Black - Black - Black, but that is actually ONE OHM. (I always have a hard time comprehending that one).   So I cant imagine how to color code ZERO Ohms...

Look165 <look165@numericable.fr>: Mar 10 10:25AM +0100 They ca over pass a track without needing 2 vias.

whit3rd <whit3rd@gmail.com>: Mar 10 02:36AM -0800 On Friday, March 10, 2017 at 1:20:22 AM UTC-8, olds...@tubes.com wrote:   [about zero-ohm resistors]   > I thought it would be Black - Black - Black, but that is actually ONE > OHM. (I always have a hard time comprehending that one).   > So I cant imagine how to color code ZERO Ohms...   One black band around the middle is a common marking.   <http://www.digikey.com/product-detail/en/yageo/ZOR-25-R-52-0R/0.0QTR-ND/18795>

dansabrservices@yahoo.com: Mar 10 04:26AM -0800 Please note that there are SMD versions of these as well. They will be marked with a single zero(0).   You will often see these used to jump a trace in SMD applications.   Dan

MJC <gravity@mjcoon.plus.com>: Mar 10 12:50PM In article <4l34ccpjfuk0sp59q67o9vdnfrmnl8lr52@4ax.com>, oldschool@tubes.com says... > resistors.... WTF. Wouldn't that be a piece of wire?   > What would be the point of that?   > How would you even color code it?   Perhaps someone is sneaking "high temperature" (meaning ambient) superconductors onto the market with no fanfare?   Mike.

oldschool@tubes.com: Mar 10 02:56AM -0600 On Wed, 8 Mar 2017 17:53:31 -0000 (UTC), frank <frank@invalid.net> wrote:   >modern. >Thanks >Frank   I have no idea what that keyboard looks like, but all keyboards can be taken apart and the cord is plugged into the board inside of it. Maybe you can use your old cord on a modern keyboard. Just a thought!

Look165 <look165@numericable.fr>: Mar 10 10:09AM +0100 The chemtronic CW2200 is a very good conductor and you can ssolder on it.   frank a écrit :

Robert Baer <robertbaer@localnet.com>: Mar 09 10:43PM -0800 John Larkin wrote: > had a PCB trace current probe, but that's probably not posssible. > You can measure millivolt and microvolt drops across traces and > vias.   You just described that PCB trace current probe; just use known trace length - with known width you get approximate current.

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