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John Robertson <spam@flippers.com>: Aug 24 10:48AM -0700 On 08/23/2015 6:10 PM, Ashton Crusher wrote: > who is skilled at left foot braking is far less likely to try to push > the accelerator with the right foot with the intention of braking. > I'm sure there are always exceptions.   And the left foot break idiot(s) who rests his/her foot on the brake pedal and thus drives around all day with their brake lights on? Not to mention wearing out the brake pads or (even worse) overheating the brakes so they fail at an inopportune time...   I see that a lot, so I vote no to left foot braking. Unless you can't use your right foot, but we are talking about folks without any sort of handicap (cast, missing foot, etc.).   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."

John Robertson <spam@flippers.com>: Aug 24 10:50AM -0700 On 08/23/2015 5:31 PM, J Burns wrote: >> risk of accidents?   > It greatly reduces the risk of brake failure. I can't use that method > with my car because they're no hole in the floor.   Hi Fred! (Flintstone)...   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."

Muggles <xyz@pdq.invalid>: Aug 24 01:52PM -0500 On 8/22/2015 8:36 PM, Ashton Crusher wrote:   > seems that such a "it's getting worse" view is hard wired into most > people as they age.   In many ways I can agree with you about things getting worse, but then something happens in the world somewhere that gives me hope.   http://www.cnn.com/2015/08/24/europe/france-train-shooting/   The 4 men who stopped the terrorist on that France train, 3 of them were young American men. There are still good people in the world who will put themselves in harms way to protect other people, and stop something horrible from happening that they actually had a chance to stop vs. looking the other way and hiding.   The news is shining the light on an event that saved lives. I think people are just tired of being terrorized and afraid.   -- Maggie

Oren <Oren@127.0.0.1>: Aug 24 12:33PM -0700 On Mon, 24 Aug 2015 10:50:22 -0700, John Robertson <spam@flippers.com> wrote:     >> It greatly reduces the risk of brake failure. I can't use that method >> with my car because they're no hole in the floor.   >Hi Fred! (Flintstone)...   Didn't Fred back pedal to slow down?

Ashton Crusher <demi@moore.net>: Aug 24 02:48PM -0700 On Mon, 24 Aug 2015 10:48:51 -0700, John Robertson <spam@flippers.com> wrote:   >pedal and thus drives around all day with their brake lights on? Not to >mention wearing out the brake pads or (even worse) overheating the >brakes so they fail at an inopportune time...   I've seen it maybe twice in 40 years. It's an imaginary problem. And for all you know they were using their right foot and had it on both the gas and brake at the same time... unless you have X-ray vision of course and could actually see their feet. Or perhaps their brake light switch was broken making the brake lights come on and off without any one pushing on the pedal. Someone who rode their brakes like that "all day" would be emitting smoke.     >I see that a lot, so I vote no to left foot braking. Unless you can't >use your right foot, but we are talking about folks without any sort of >handicap (cast, missing foot, etc.).   No one has suggested that people should left foot brake if they don't have the skills necessary. Some people just aren't trainable or don't have the ability, or are too easily confused for anything above bare minimum.

Ashton Crusher <demi@moore.net>: Aug 24 03:08PM -0700 On Sun, 23 Aug 2015 18:48:37 -0600, nmassello@yahoo.com (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?   Seems unlikely. Do pilots mash the bottom part of the Rudder pedal which also controls the front steerable wheel instead of the top part of the pedals that controls the brakes when they want to stop on the ground?   In my experience as a driver and pilot those things just don't happen. Even if it did, there's no reason it would be any more likely than right foot brakers mashing the accelerator instead of the brake in a panic situation. Since with LFB each foot has a defined task instead of the right foot sharing two tasks there is reason to think it would be less likely.

Ashton Crusher <demi@moore.net>: Aug 24 03:09PM -0700 On Sun, 23 Aug 2015 20:16:39 -0500, "Dean Hoffman" >> risk of accidents?   > Didn't Toyota make some claims about that? There was a recall for >driver side carpets if I remember correctly.   That was for unintended acceleration, not foot confusion.

rbowman <bowman@erewhon.com>: Aug 24 07:44PM -0600 On 08/24/2015 04:08 PM, Ashton Crusher wrote: > which also controls the front steerable wheel instead of the top part > of the pedals that controls the brakes when they want to stop on the > ground?   I flew an old Lark and got in the habit of pumping the brakes up on final. Just another thing to add to the checklist...

kludge@panix.com (Scott Dorsey): Aug 25 09:30AM -0400 >light switch was broken making the brake lights come on and off >without any one pushing on the pedal. Someone who rode their brakes >like that "all day" would be emitting smoke.   What if you are mutant with three feet? Then you could operate the brake, clutch, and accelerator independently. It would make waltzing easier too. --scott     -- "C'est un Nagra. C'est suisse, et tres, tres precis."

"pfjw@aol.com" <pfjw@aol.com>: Aug 24 10:40AM -0700 On Sunday, August 23, 2015 at 1:43:24 PM UTC-4, Cursitor Doom wrote: > down. > And I'm also guessing one could get away with starting the process at > 50VAC? What does the Panel think?   Mpffff.... a variac without proper metering is worse than useless. And a dim-bulb tester, while infinitely better than an unmetered variac is still a blunt instrument.   A variac needs an ammeter that is accurate within a single % of the scale it is measuring. Such that one may watch even tiny variations in how the current comes up as the voltage is raised. A few things:   a) Anything with a tube (valve) rectifier will not pass B+ until the applied voltage is somewhere between 70% and 80% of the nominal voltage. So, reforming caps by way of slow uptake on a variac for such a devices is a complete myth. Those caps will see, all at once, no less than 70% of the operating voltage - not hardly a soft start.   b) If any device is using as little as 5% more current than it should-if-optimal, that current will be expressed somewhere as heat. If in the winding of a power or output transformer, that will, eventually mean *POOF*. If in an IF transformer for a tuner or receiver, also, eventually, *POOF*.   c) Electronics, old and new, do not typically 'cure' themselves of faults, even if cajoled, massaged and seduced very slowly. Sure, caps _can_ reform, but that reformation is unlikely to be either reliable or permanent. Given the low cost of caps these days, even the thought of reforming vintage caps should give one the cold shivers at the very least.   d) One can, with the proper instrumentation, figure out what is going on with any given piece of equipment typically within several hours anyway. 99-44/100% of them, within several minutes. Sure, individual component thermal failures or intermittents can be a huge diagnostic problem, but as to general function, that should take little time at all.   So, cutting to the chase, a metered variac with a precise meter that is capable of reading *accurately* in very small increments is a very fine diagnostic tool, especially at the triage level. A simple, unadorned variac is useful only for dimming the lights - its original purpose. IF that is all one has, put it aside and start with the dim-bulb tester and a number of different 'bulbs' to get a very-ballpark S.W.A.G. at how much current any given devices is actually using.   For the record, if it takes me more than 5 minutes to conclude how well behaved any given device might be under full power, that would be a long time. HOWEVER!! Once any new-to-me device is at full operating voltage and running, I will watch it like a hawk for several hours at least before deeming it fit for polite society. And very few very vintage (pre-1960) devices get even that far without at least the power-supply caps being redone. It is simply not worth the risk.   Peter Wieck Melrose Park, PA

"pfjw@aol.com" <pfjw@aol.com>: Aug 24 10:47AM -0700 On Monday, August 24, 2015 at 1:27:44 AM UTC-4, Phil Allison wrote:   > 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.     How would that happen unless the unit had a solid-state rectifier? Typically that quick-rise, slow-fall is due to the "empty" caps accepting inrush, then as they charge becoming more 'resistant-for-lack-of-a-better-word'. And the only way the caps would be in the circuit is if the rectifier was in place - hence the question.   Put another way, it is a bad idea to allow a tube amp to make B+ without a load. Many marginally designed amps ran their filer caps at very near their ratings - and both vintage and marginally capable caps running unloaded might just go *POOF*.   Peter Wieck Melrose Park, PA

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Aug 25 07:17AM +1000 >> 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 ?   **No.   -- Trevor Wilson www.rageaudio.com.au   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

jurb6006@gmail.com: Aug 24 04:32PM -0700 >"** 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. "   I'll take your word for it, but that doesn't explain why. I dug around a little and found the TA-8650 which is 80 watts per and uses three complementary sets of 2SK60 and 2SJ18 per. Seems like alot for 80 watts but who am I to bitch about something being a bit overbuilt ?   There are a couple of things about that amp that don't make a hell of alot of sense. First of all, they are current sharing without source resistors, at least separate source resistors. you said there aren't many that can do that, apparently these are among them. And they use two source resistors, damn, for an extra ten cents they could have just used three. I also caught an error where they claim to have -85 volts on the base of a transistors with the emitter grounded. But I am used to that shit.   Also, they are drawn as depletion mode devices, yet have a higher source for the drivers. (they ARE depletion mode right ?) OK, that might just be for better linearity but I bet those outputs REALLY don't like hard clipping. Yeah sure don't do that, but it should not be destructive. shit happens like when switching sources or whatever sometimes.   And neither should brownouts. I don't see how running off a variac at reduced voltage would fry this thing. But my search indicates that such devices were also used in some serious high end monoblocks but I did not get those model numbers. Any come to mind I can look up ?   Sony failure modes have been a bitch for a long time. Seems like they used to love selling alot of parts.

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Aug 25 11:32AM +1000 > three complementary sets of 2SK60 and 2SJ18 per. Seems like alot for > 80 watts but who am I to bitch about something being a bit overbuilt > ?   **The 2SK60/2SJ18 are rated at a pitiful 5 Amps, which is why so many are required. Here is what is printed on page 6 of the service manual of the Sony TAN7:   "Note: 1. Apply the rated ac line Voltage to the set directly. Do not increase the Voltage gradually by using a variable transformer or other such instrument; this will cause a V-FET failure."     > reduced voltage would fry this thing. But my search indicates that > such devices were also used in some serious high end monoblocks but I > did not get those model numbers. Any come to mind I can look up ?   **I recall my first V-FET amp repair. I did not pay attention to the Sony Warning. A new set of V-FETs and I was good to go, after blowing up the first set. Every V-FET amp since has been VERY carefully dealt with. No bench failures since the first one. The most expensive and unique amp I've ever seen was the Yamaha B1. It was a beast, with over-sized V-FETs. They LOOK like To-3 devices, until you see one in the flesh:   http://www.thevintageknob.org/yamaha-B-1.html   http://upload.review33.com/avforum/201507/201507092155125540.jpg       > Sony failure modes have been a bitch for a long time. Seems like they > used to love selling alot of parts.   **No different to any other company.       -- Trevor Wilson www.rageaudio.com.au   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

dplatt@coop.radagast.org (Dave Platt): Aug 24 07:53PM -0700 In article <d41uv0FspljU1@mid.individual.net>, >No bench failures since the first one. The most expensive and unique amp >I've ever seen was the Yamaha B1. It was a beast, with over-sized >V-FETs. They LOOK like To-3 devices, until you see one in the flesh:   That feels to me more like a design flaw in the circuitry... something which mis-biases the VFETs if the rail voltages don't come up and down at the prescribed speeds. Possibly the gate voltages rise faster than the drains, and the gate/source or gain/drain voltage limit is exceeded?   A power amplifier that will fry its output stage if the mains voltage bounces around (say, during a "brownout" of commercial power) really seems like a poor design to market.

Phil Allison <pallison49@gmail.com>: Aug 24 09:33PM -0700 > > With all valves removed, the AC supply current rose quickly > > with each voltage increases and then slowly fell back.   > How would that happen unless the unit had a solid-state rectifier?   ** It wouldn't.   Soon as silicon diodes became available in the 1960s, designers used them to replace the inefficient and troublesome valve rectifiers in TVs and amps of all kinds. A further efficiency was obtained by using four diode bridges or two diode voltage doublers and eliminating the centre-tapped secondary needed with valve "full wave" rectifiers.     > > Typically that quick-rise, slow-fall is due to the > > "empty" caps accepting inrush, then as they charge > > becoming more 'resistant-for-lack-of-a-better-word'.   ** Inrush surges as you increment a variac are normally very brief, but in this case they were sustained, taking many minutes each time for the current to fall back to the residual being drawn by the primary of the transformer. I well knew this meant dodgy filter electros.   On my bench, the variac's output is followed by a 3.5 digit current meter with 1mA resolution and a (safety isolated) waveform output to view on a scope. 100Hz current pulses being drawn by filter electros appear very distinct from the steady 50Hz current draw of the power transformer.   With good electros and no valves installed (or the standby off), current pulses should be absent.     > their filer caps at very near their ratings - and both > vintage and marginally capable caps running unloaded might > just go *POOF*.   ** It's something to be aware of and one should check electro voltage ratings to make sure they are not being exceeded in this condition.   BTW: I have come across a few modern valve amps where electros further down the chain from the main filters were of such lower voltage that removing some of the preamp valves caused their rating to be exceeded.   .... Phil

Phil Allison <pallison49@gmail.com>: Aug 24 11:03PM -0700 Dave Platt wrote:   > at the prescribed speeds. Possibly the gate voltages rise faster than > the drains, and the gate/source or gain/drain voltage limit is > exceeded? ** Take a look at the power stage schem here:   http://www.angelfire.com/sd/paulkemble/sound8f.html   Note the unusual crosswise connection from the drive stage to the six V-FET followers.   The V-FETs used behave like J-FETs requiring reverse polarity gate bias voltage to turn them off, with zero bias they conduct heavily - the opposite of the case with transistors and MOSFETS.   So, when using a variac, a condition must exist where the needed reverse bias is missing but the V-FETs have enough DC supply available to fry themselves if held there.       .... Phil

jurb6006@gmail.com: Aug 24 11:38PM -0700 >"So, when using a variac, a condition must exist where the needed reverse bias >is missing but the V-FETs have enough DC supply available to fry themselves if >held there"   I understand that, but there should be a way to design around it, prevent it from happening. Piss poor IMO. Asking for trouble. How many times the power went out and came back dim, like half voltage. And varied. Would they cover that under warranty or would I have to sue the power company ?   They might be able to design a lower distortion circuit than I but they leave much to be desired in practicality, especially in a supposedly high end unit. If they are going to charge top buck for this shit they should have included a UPS. Or something.   I do not mind making money off of their follies, but that puts my name on it. What, I gotta install a light sensor to see if the customer's lights dim which voids the warranty on the work ? Ridiculous. Tell you what, they are scrap on sight as of now.   Fuck, there are so many ways to prevent that failure mode it is ridiculous. One stupid power relay that removes the rail voltage form the outputs would do it, and then they wouldn't need one at the speaker output. Very low cost.   Fucking assholes. I really used to like Sony stuff, but not so much their audio. I didn't like the sound of it. Now I am glad, I didn't buy that thing, I didn't buy the highly coveted STR-V6 I had on loan for like a couple of weeks. I did buy one of their cassette decks though and it was alright. And I do still have their (real) VCRs. And SLV-920HF I need to lube before firing up and an SL-HFR60 with the processor. I have a shitload of beta tapes. I am looking for a good deal on a standalone DVD recorder so I have real backup and then I intend to rip to harddrive certain things., I will be a youtube star, Man those times were wild. Like when I almost got run over by a car taping an outdoor concert on someone's porch. Instructions on how to roll a joint. Damn, there is so much I forgot, but the deal is this is so old that I might only get one chance, so I am not sitting here playing it. In fact I owuld like to have a beta rewinder so I don't have to beat on the reel motor, they were a high failure item.   But after that, Sony and I are through. I will never buy a new product from them again and I have serious doubt about a used one. Yes, I bought that thousand bucks worth of VCRs brand new.   But now that we're on the subject, it might be a good idea to mention other things that do not take kindly to a variac or a DBT. They are out there. I can see that some of the class D amps would not like it. Things with SMPSes. What else ? I am sure there are more but I just don't know what.

Phil Allison <pallison49@gmail.com>: Aug 25 03:13AM -0700 > > enough DC supply available to fry themselves if held there."   > I understand that, but there should be a way to design around it, > prevent it from happening. Piss poor IMO. Asking for trouble.   ** Only if you use a variac with one.     > How many times the power went out and came back dim, like half voltage. > And varied.   ** I have seen that happen only once in my life, about 20 years ago.   Of course you need to have the amp switched on and not bother to turn it off when the power outage happens. Prolonged brown can damage stuff, like the compressor motors in fridges - and they are always left on 24/7.   > it is ridiculous. One stupid power relay that removes the > rail voltage form the outputs would do it, and then they > wouldn't need one at the speaker output. Very low cost.   ** The amp is already bristling with add on circuits that constantly tweak the bias, protect the V-FETs from current overload and stop DC appearing at the speaker terminals. All not shown in the simplified schem I linked.   FYI: the DC bias across R737 is anywhere from 20 to 50 volts, depending on the particular V-FETs actually fitted, the ambient temp and the DC supply voltage.   > Fucking assholes.     ** Crikey, it don't take much to wind "jurb" up.       ... Phil

Phil Allison <pallison49@gmail.com>: Aug 25 03:28AM -0700 > > http://www.angelfire.com/sd/paulkemble/sound8f.html   > There are a couple of things about that amp that don't make a hell of alot of sense. First of all, they are current sharing without source resistors, at least separate source resistors. you said there aren't many that can do that, apparently these are among them. And they use two source resistors, damn, for an extra ten cents they could have just used three.   ** The parallel 0.47ohm resistors are there for the VI limiter circuit ( not drawn) saving the V-FETs from destruction if driven into a low impedance or short.   > Sony failure modes have been a bitch for a long time. > Seems like they used to love selling alot of parts.     ** Sony seem to like showing everyone how clever they are with over-complicated circuits and mechanics too.   Reminds me a lot of Grundig, Crown and Dynacord.     ... Phil

jurb6006@gmail.com: Aug 24 11:42PM -0700 You got lucky, there are a bunch of different sizes of those threads, at least here in the land of the rapeable consumersheeple.

Jeff Liebermann <jeffl@cruzio.com>: Aug 24 02:48PM -0700 >AE6KS ..... how about live oak ? >or in your area...dead oak.   Yep. We're slowly loosing our local white, red, and tan oaks to phytophthora ramorum (sudden oak death). <http://www.suddenoakdeath.org> <http://www.dontmovefirewood.org/gallery-of-pests/sudden-oak-death-syndrome.html> <https://en.wikipedia.org/wiki/Phytophthora_ramorum> Rumor has it that it's caused by puns and bad joaks.       -- 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>: Aug 24 01:00PM -0700 On Tuesday, August 18, 2015 at 1:25:21 PM UTC-4, Smarty wrote: > Two physicians walk into a bar.....   But the bartender did not know what to do with a paradox.....

etpm@whidbey.com: Aug 24 02:09PM -0700 On Tue, 18 Aug 2015 17:23:35 +0000 (UTC), Smarty <nobody@nobody.com> wrote:   >Two physicians walk into a bar..... And both fell down.

nmassello@yahoo.com (Neill Massello): Aug 24 11:35AM -0600 > I learned on a clutch car.   If you've got a clutch pedal, left-foot braking is a non-starter -- er, stopper.

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