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Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Mar 30 07:00AM +1100 >> result can be very >benign. "   > They're all benign when not active. I am talking about when they are > working actively limiting current. Maybe I didn't make that clear.   **And I explained that, if the current limiting system can be kept out of the NFB loop, then it's action can be benign.     > But if I did, and there is a scheme that will limit the current > actively without that harsh distortion, show me. A model number will > do now that with the internet I can usually get a print.   **Do the analysis based on my description. I am aware of at least a dozen products where the current limiting system is not contained within the NFB loop and the result is gentle limiting. Schematics are not generally available, AFAIK.   > or something like that. Overload it and it seemed like the gain > decreased, it didn't bark at you. But it also was not all that high > end or high power.   **There you go. I know of one amp that used a simple lamp to limit current through the output stage under overload.     >> "**That is the way high quality products do it."   > At the cost of market share of course. I agree though, just build it > right and use like 12 amp speaker fuses.   **No high end amplifier uses non-linear resistors (aka: fuses) in series with speakers. To do so, would be the antithesis of high fidelity.     > HA, I remember Heathkit touted that their speaker fuses were in the > feedback loop. Actually, the audiophile crowd kinda likes them.   **Not me. Fuses should be there to prevent fires. Nothing more.       -- Trevor Wilson www.rageaudio.com.au   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

"pfjw@aol.com" <pfjw@aol.com>: Mar 29 03:18PM -0700 On Tuesday, March 29, 2016 at 4:00:24 PM UTC-4, Trevor Wilson wrote:   > **No high end amplifier uses non-linear resistors (aka: fuses) in series > with speakers. To do so, would be the antithesis of high fidelity.   Please explain with other than anecdotal information. This reads suspiciously like advocating high-cost interconnects, line cords, and speaker wires....     Peter Wieck Melrose Park, PA

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Mar 30 09:58AM +1100 >> **No high end amplifier uses non-linear resistors (aka: fuses) in series >> with speakers. To do so, would be the antithesis of high fidelity.   > Please explain with other than anecdotal information. This reads suspiciously like advocating high-cost interconnects, line cords, and speaker wires....   **Now you're being silly. Measure a fuse sometime. The resistance increases, as current increases. It acts as a non-linear resistor. The ONLY place for a fuse is before filter capacitors in an amplifier. In the DC lines, or the speaker lines, fuses introduce distortion and should not be used. This is electronics 101.   For the record:   * People using fancy power leads are deluded. The best power leads are, of course, old style captive ones. IEC connectors are convenient and stupid. They allow consumers to be conned into changing power leads needlessly. * People using *LOW INDUCTANCE*, *LOW RESISTANCE* speaker cables may not, necessarily, be deluded. Again: Electronics 101.   Here are a couple of examples why such speaker cables may be useful:   http://www.rageaudio.com.au/modules/gallery/view.php?a=Accustat&image=091027105452_accu.jpg http://www.rageaudio.com.au/modules/gallery/view.php?a=Kappa9&image=090801082656_kappa9.jpg     Never throw the baby out with the bathwater. Electronics 101.     -- Trevor Wilson www.rageaudio.com.au   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Mar 30 12:06PM +1100 On 25/03/2016 9:48 PM, Mark Zacharias wrote:   > Shit for brains god damn idiot. I knew better that this when I was > sixteen fucking years old!   > I'm reminded of Chevy Chase's rant in Christmas Vacation...   **I have only done once or twice, but with a couple of recalcitrant clients, I have installed Polyswitches into their equipment. Mostly speakers, but sometimes amplifiers.     -- Trevor Wilson www.rageaudio.com.au   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

"pfjw@aol.com" <pfjw@aol.com>: Mar 30 09:30AM -0700 On Tuesday, March 29, 2016 at 6:58:21 PM UTC-4, Trevor Wilson wrote:   > ONLY place for a fuse is before filter capacitors in an amplifier. In > the DC lines, or the speaker lines, fuses introduce distortion and > should not be used. This is electronics 101.   Silver-link fuses using an eutectic formula add negligible resistance within their ratings. Nor are they cheap. As you well know, silver is the closest thing to a super-conductor at any reasonable operating temperature as exists in nature, much better than copper (or gold), and so such fuses ought to be considered.   Example: I keep speakers from a current manufacturer that would cost me well over US$7,000 to replace today. A few bucks on fuses to protect this investment is well worth it. That I researched dual-element silver-bearing fuses to minimize any downside from adding such a device makes the choice both worth it and (probably) wise. A defective amp is not likely to gradually ramp up into the speakers, it is likely to surge - at least in my experience. So, I can run the fuse very close to the overall speaker rating letting the dual-element section handle high musical peaks without sacrificing (much) protection.   Keeping in mind that as you suggest, low-resistance speaker connections are a 'good' thing, I use #12 fine-stranded (19 strands) THHN wire for speaker leads, spun in a drill to reduce capacitance does well for short runs and is remarkably cheap at ~US$0.27/foot (both stands included).   But, a fuse on a $3,500 speaker?   Wouldn't you?   Peter Wieck Melrose Park, PA

"Mark Zacharias" <mark_zacharias@sbcglobal.net>: Mar 30 07:03AM -0500 Circa 1987   Harman Kardon HK-400XM:   Three-head cassette deck.   Intermittent failure to record on one channel. Playback fine.   Customer sent to HK twice for factory service.   Twice HK replaced the record / play head assembly. Problem persisted.   On the bench, at failure mode, discovered full peak-to-peak bias at the output of the affected channel, swamping out the audio.   Defective (intermittent coil) in bias trap. IIRC a small module.   That customer still looks me up 30 years later when he has a problem.   Couple years later, same problem on a Kenwood KX-1030. Open coil.   Over 30 years - never seen this since.     Mark Z.

N_Cook <diverse@tcp.co.uk>: Mar 29 05:58PM +0100 On 22/03/2016 14:01, N_Cook wrote: > tyres in tape decks), completes the universal rubber tool kit. > Plus remnants in pic. minimum I've "bean sliced" down to without > breaking is about 0.3mm thick.   half price Aldi , remaindered after easter now

Colin Horsley <horsley-spam@westnet.com.au>: Mar 30 08:30PM +1100 On 29/02/2016 16:14, DaveC wrote:   > (If you're just going to Google, don't bother, I've already done > that…)   > Thanks!   Try here:-   https://www.wes.com.au/mediapub/ebook/wescat2014np/#1220   Colin       --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

Gunther Heiko Hagen <guntherxxx@quantserve.de>: Mar 29 10:19PM On Tue, 29 Mar 2016 11:27:28 -0400, Michael A. Terrell wrote:   > Then explain why Florida has started farming hops instead of oranges, > in many places.   For export, of course.

Phil Allison <pallison49@gmail.com>: Mar 29 11:16PM -0700 Heiko Hagen wrote:     > They don't appear to use hops for flavouring in N. America and Australia,   ** America produces 28,000 tonnes of hops per year - practically all of it going into beer. Only Germany produces more, with 34,000 tonnes.   https://en.wikipedia.org/wiki/Hops#Cultivation_and_harvest   Thing is, they probably don't use enough of it in each barrel to suit you.   Small and craft brewers generally use a lot more malt and hops per barrel than the big commercial ones.       .... Phil

Jeff Liebermann <jeffl@cruzio.com>: Mar 29 05:31PM -0700 On Mon, 28 Mar 2016 22:46:04 -0500, "Dave M" <dgminala@mediacombb.net> wrote:   >Jon,   Methinks that you mean't me.   >What are the dimensions of the light ring (ID, OD, thickness)?   ID: 60 mm OD: 96 mm (not including lock screws and power connector). Thick: 30 mm   Adjustable power supply: Model: LC-P800 Input: 90-240VAC 50/60Hz Output: 10-12VDC 750 ma Max     -- 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

"Dave M" <dgminala@mediacombb.net>: Mar 29 10:07PM -0500 Yes, Jeff, I was addressing the question to you; sorry if I was ambiguous. Thanks for the info.   Dave M     Jeff Liebermann wrote:

Jeff Liebermann <jeffl@cruzio.com>: Mar 29 07:15PM -0700 On Mon, 28 Mar 2016 22:15:42 -0500, Jon Elson <elson@pico-systems.com> wrote:   What does this suppose to mean, do, or prove? Newsgroups: Choose,an,appropriate,group,to,redirect,replies... If you want to black hole replies, just redirect to /dev/null   Newsgroup changed to: sci.electronics.design,sci.electronics.repair     >I've heard these stories a number of times. And, yes, maybe some people use >insanely hot irons or in some other way cause this problem. And, some >really large caps are prone to this damage.   Yep. As James Arthur mentioned, it's not a problem with the physically small caps, which come to a uniform thermal equilibrium rather rapidly. It's only the big caps, with lots of plates, thin low voltage ceramic dielectric, and larger thermal mass, that were a problem for me.   >But, as I say, I have hand- >soldered over 25,000 0805 MLCC caps of modest value without seeing this >problem.   One exception will break any such rule. Dig out a larger and higher capacitance MLCC cap in a 1210 or larger package. Try soldering it with a single soldering iron. Unless you're very good, it won't take much to trash the cap.   <http://www.avx.com/products/ceramic-capacitors/high-voltage/high-voltage-mlc-chips/> "Chip sizes 1210 and larger should be reflow soldered only."   >I use a very good Weller temperature-controlled iron, and run it >at a modest temperature.   I use several ancient Weller WTCP TC201 and TC202 (because they were free) soldering stations. Most of my tips are 750F with a few at 850F.   >Much better to use an iron with really good >thermal conductivity at a lower temperature than one with poor conductivity >at a very high temperature.   I don't understand. All the tips are made of plated iron. There's little difference in thermal conductivity between tips, unless you want to throw in copper tips heated with a gas burner. What part of the soldering iron varies in thermal conductivity?     -- 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>: Mar 29 11:14AM -0700 On 03/24/2016 1:44 AM, Top Cat wrote: >> www.flippers.com >> "Old pinballers never die, they just flip out."   > Hi John, if I could look at what you have that might be the answer to my prayers. I can't find your e-mail though. Am I being dense? Is it glaring at me somewhere? Cheers.   Hi Chris,   I have now scanned my files and they are legible. Is there any marking on your monitor? Letter and number codes? Failing that, what is the number on the picture tube?   I scanned these as TIFs and they are huge (100mb) because they are blueprints. If anyone can convert scanned blueprints to straight B&W I would be happy to share these via dropbox.   My return email is valid! Or replace spam with jrr if you prefer.   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 or Fax 872-2010 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

jurb6006@gmail.com: Mar 29 04:09PM -0700 >"I scanned these as TIFs and they are huge (100mb) because they are >blueprints. If anyone can convert scanned blueprints to straight B&W >I >would be happy to share these via dropbox. "   Pretty sure I can do that in PSP, and save them in JPG format so they aren't so huge.

"Gareth Magennis" <soundserviceleeds@outlook.com>: Mar 29 10:34PM +0100 "T i m" wrote in message news:3ekkfb9h7n1hagj2h45imjq8p3knmf1794@4ax.com...   On Tue, 29 Mar 2016 00:34:20 +0100, "Gareth Magennis" <soundserviceleeds@outlook.com> wrote:   <snip>   >I only want to blow dust off a heatsink. I can actually do this myself by >taking a big breath and blowing hard.   I've done that for someone on an overheating PC but using a thin tube to better direct the air and get my face out of the way. ;-)   >But I really don't want to do that, and I don't want a large compressor >plus >tank I have to store somewhere to do this for me.   I've not read the entire thread but I have a very portable and 'adequate' instant / oil-free, non reservoir compressor I regularly use for blowing out PC heatsinks and cases and have done so for many years now (to good effect).   http://nbwelly.en.made-in-china.com/product/EeyQOYrlbXWg/China-1-5HP-Oil-Free-Portable-Air-Compressor-Without-Tank.html   http://tinyurl.com/hn3xonj   My mate (who owns his own PC repair shop) has the exact same and has been using his for a similar period. The only thing against them, you do need power and they are pretty noisy (but aren't generally running for long). Personally, I leave mine just inside an external door, just close the door on the hose and blow the item clean outside (so not so noisy).   <snip>   >has the right attachment for blowing up at any local garage. >http://www.puretyre.co.uk/tyre-information/tyre-definitions/space-saver-tyre/   >I just need a smaller tank to do the same job.   As I believe has already been mentioned, you don't get a lot of 'compressed air' when you aren't compressing it to very high pressures so you may be stuck with something that is still reasonably bulky. A spare wheel may well be good enough and as you say, already has the right connections, at least for inflation. ;-)   I bought one of these to do exactly the sort of thing you were talking of:   http://www.toolstation.com/shop/Power+Tools/d40/Air+Compressors+%26+Accessories/sd3147/Trade+24L+Air+Receiver/p19659   http://tinyurl.com/zjonb68   I have to admit I've not used it yet but I hope to soon, both to expand the capacity of my small silent workshop compressor (Bambi) and to have something in the indoor workshop for the odd small blowing out job (that I can re-charge myself down the workshop on the other compressor).   Cheers, T i m             Thanks, Tim.   I was a little bit hasty in suggesting a 60 psi spare tyre might be a solution. I tried it earlier to realise the valve is just designed for slow filling, and has a very restricted airflow when deflating. (Which I knew already but just plain forgot)       Point is, it doesn't take an awful lot of air to blow dust off a heatsink. I usually brush off what I can before resorting to using my lungs and blowing off the remaining inaccessible stuff. Trouble is this always ends up with some in my lungs and nasal passages.     Cheers,     Gareth.

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