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Phil Allison <pallison49@gmail.com>: Aug 23 10:27PM -0700 Cursitor Doom wrote:   > *years*, what rate would it be advisable to slowly wind up the supply > voltage to it so as not to blow anything? I'd guess 24hrs for a 240VAC DUT > would do it but it's just a guess.     ** That would probably be very safe, but in most cases it can be done much faster. Filter electros are the troublemakers as they can require gradual reforming after a long period of idleness.   Had one like that the other day, a valve amp from the 1960s that had not been run in the last 10 years. With all valves removed, the AC supply current rose quickly with each voltage increases and then slowly fell back.     > after being too impatient; very annoying. Whichever component it was that > went phut filled the room with acrid smoke. I still have yet to track it > down.   ** That is what overheated electros do.     .... Phil

gregz <zekor@comcast.net>: Aug 24 07:43AM > down. > And I'm also guessing one could get away with starting the process at > 50VAC? What does the Panel think?   Not much more, but all depends, of course. Then you got tube rectifiers. I like using dim bulb AND variac. I don't know if it helps, but sometimes I let sit at zero, after slow increases.   Greg

N_Cook <diverse@tcp.co.uk>: Aug 24 09:24AM +0100 On 23/08/2015 18:41, Cursitor Doom wrote: > down. > And I'm also guessing one could get away with starting the process at > 50VAC? What does the Panel think?   Tantalum caps failing, can go off with quite a bang, leaving an "electrical" smell

jurb6006@gmail.com: Aug 24 02:55AM -0700 >"**One more trap for the uninitiated: NEVER crank up an audio amplifier >fitted with V-FET output devices on a variable auto-transformer. >Destruction will be assured under such a test. "   You mean class D I assume ?

Phil Allison <pallison49@gmail.com>: Aug 24 06:00AM -0700 > >fitted with V-FET output devices on a variable auto-transformer. > >Destruction will be assured under such a test. "   > You mean class D I assume ?     ** V-FETs were TO3 linear devices made and used by Sony and Yamaha in a number of hi-fi amplifers back in the mid 1970s. Common part numbers were 2SK82 and 2SJ28.   Then they suddenly stopped making them.   As a result, V-FETs and the few amps concerned are now rare and so have acquired a mythical status among the gullible.   BTW:   Do not confuse V-FETs with Hitachi's "Lateral Mosfets" that appeared later and were a huge success especially in high powered pro-audio amps.   Common numbers were 2SK135 & 2SJ50 or 2SK176 & 2SJ56.   Then they suddenly stopped in the late 1980s.   However, near identical TO3 MOSFETS are still made and carry numbers like BUZ901 and BUZ905.     ... Phil                       Google " Sony V-FET " and learn more than you ever wanted to know.

Cursitor Doom <curd@notformail.com>: Aug 24 03:12PM On Mon, 24 Aug 2015 09:24:38 +0100, N_Cook wrote:   > Tantalum caps failing, can go off with quite a bang, leaving an > "electrical" smell   Probably not a tant, then. I don't recall any bang and certainly no electrical smell. Just choking, acrid smoke. Oh, and when I looked inside, there was a light film of fine, sooty, black carbon powder over much of the innards. I suspect whatever had failed was concealed or screened as I couldn't see any evidence of charred components merely from splitting apart the external cases.

N_Cook <diverse@tcp.co.uk>: Aug 24 03:54PM +0100 A large Behringer mixer returns with intermittant loss of one or both channels due to being used outdoors and dust/damp getting on the L&R Main Insert bypass contacts. As the main inserts are rarely used I decided to add a pair of captive dustcaps, after replacing the sockets this time . It just happens the hex "nut" part of F connectors is the same thread of these metal bushed sockets. 2 part crimp type with a core barrel and a larger cylinder crimped over, in normal use. Ground off the inner cylinder and ground a slight slot in the remaining disc, that is free to rotate in the hex, to take some silicone sleeving. That sleeving swathed in coloured hotmelt, filling the exposed top part of the disc . The other sleeve-end knotted to a solder tag using a convenient fixing screw. Then a disc of rubber cut with leather punch to go inside the hex , to seal to the top of the socket, on screwing down the hex.

The Real Bev <bashley101@gmail.com>: Aug 23 11:00PM -0700 On 08/23/2015 02:58 PM, Dean Hoffman wrote:   >> European or Japanese?   > I got to ride a Norton once, long ago. I think there was some > odd critter with an actual hand gear shift.   And then there was the Harley suicide clutch...   For a while I rode a 1960 Ducati street bike and a 196x Honda dirtbike. Even if I think about it now I can't decide which is the 'correct' Japanese side to shift on, I have to find a picture. At the time, dirt triggered one shift method and street triggered theother one. I still can't remember which is 1 up four down or 1 down 4 up.   http://cybermotorcycle.com/gallery/ducati/images/Ducati_1968_Monza_250.jpg . It's not. The tank is just like mine, although I can't verify that all my parts were stock. I painted it orange.   And then there were the two different Japanese metric threads...     -- Cheers, Bev "At the core of liberalism is the spoiled child, miserable, as all spoiled children are, unsatisfied, demanding, ill-disciplined, despotic and useless. Liberalism is a philosophy of sniveling brats." PJ O'Rourke

Stormin Mormon <cayoung61@hotmail.com>: Aug 24 08:09AM -0400 On 8/23/2015 8:48 PM, Neill Massello wrote: >> risk of accidents?   > In a panic situation, do left-foot brakers tend to mash down both pedals > (brake and throttle) at the same time?   Not me. I learned on a clutch car.   -- . Christopher A. Young learn more about Jesus . www.lds.org . .

N_Cook <diverse@tcp.co.uk>: Aug 24 09:30AM +0100 On 23/08/2015 11:32, N_Cook wrote: > of nuts either side. I could then increase the length of the studding > rod a bit, so it will bow outward, and stay in position, to increase the > freeboard to the bottles.   6mm studding, cut to 545mm long. I decided to angle the anchor holes, to also bow out the rod. 56mm between holes of the steel brace, twisted 90 deg along it and about 60 degree bend across it at the chassis end. Quite an easy job. I'd hate to think how much of a workup it would be drilling holes in this stainless steel chassis , let alon hank shanks inside. No fixing holes in the cab ,either, for a part back board.

Jeff Liebermann <jeffl@cruzio.com>: Aug 23 08:59PM -0700 >Does that app exist for iOS? I didn't see it.   Nope. Apple has decided that you should not be allowed to install wi-fi sniffer, monitor, and troubleshooting applications on Apple handsets. Apple knows what is best for you. This is typical: <http://www.adriangranados.com/blog/where-did-wifi-analyzer-go> Limitations like this is why I gave up on IOS long ago.   Of course, that's why people jailbreak their iPhones. Try the Cydia store on your jailbroken iThing: <https://cydia.saurik.com> Firing up my ancient iPhone 3G (jailbroken), I find - yFyLite Network Finder and nothing else. There might be something newer. I just ran Cydia to see if there's anything new, and it's furiously updating packages and indexes. Yawn... Argh, this thing is slow. How could I ever have used it? The Cydia listing shows a huge list of WiFi related utilities. A few are similar to WiFi Analyzer. The others are connection managers and password managers. Most are useless tweaks changing the stock signal stength icon to something more interesting. One I recall from long ago is WiFiFoFum with its goofy radar like display.   Of course, if you have a laptop, Apple allows Wi-Fi monitoring for OS/X: <https://itunes.apple.com/us/app/wifi-explorer/id494803304?mt=12> <https://itunes.apple.com/us/app/wifi-signal/id525912054?mt=12> Any semblance to hypocrisy is hopefully coincidental.   -- 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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