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| mike <ham789@netzero.net>: Oct 26 07:38PM -0700 On 10/26/2016 5:41 PM, whit3rd wrote: > On Wednesday, October 26, 2016 at 3:19:48 PM UTC-7, Ivan Vegvary wrote: >> I thought if I could see all the ignition activity at the same time (or at least 4 at a time) I could look for anomalies and identify a poorly firing spark plug or semi-faulty wire. > A transformer clip-on probe can trigger your 'scope from cylinder > 1, which simplifies the analysis if your auto has a single coil for all the > cylinders. You have to be careful NOT to assume normal conditions when detecting faults, which by definition, are NOT normal conditions. Stuff happens. It's best if that stuff doesn't happen when you're probing around with an expensive digital scope. 300V might be a fine number under normal circumstances, but, if a wire is bad and the plug fires at a much higher coil secondary voltage, the primary may also show a much bigger spike. And there's always the temptation to crank up the sensitivity to see some smaller wiggle on the trace. That may be a bad idea in this case. A plug either fires or it doesn't. If it fires, the thing you are interested in is the current. After it arcs, the voltage will be determined by the plug and wire/coil resistance/inductance. High current >> fat spark >> good. Of course, that assumes that the current is all going thru the plug and not arcing to ground thru a crack in wire insulation. If you have a clip-on current probe of known transient response, you can clip it on the coil output and look at the relative currents for all the cylinders. Properly insulated current probe designed for ignition service should be safe to use on your scope. If you try to move the probe to different plug wires, you'll probably see more variation in the coupling than in the actual signal. It's a vintage car. If it runs, drive it proudly. If it runs like it has ignition problems, change the plugs. If that doesn't fix it, work your way back toward the battery. Run it in the dark and poke around the wires with a grounded probe to look for insulation faults. You can learn some interesting things by pulsing the coil with the engine off and listening to the coil. But, you can smoke the coil if you're not careful. Rule number one... If it ain't broke, don't try to fix it using your expensive scope. Rule number two... If it IS broke, don't try to fix it using your expensive scope, except as a last resort. |
| "tom" <tmiller11147@verizon.net>: Oct 28 07:47PM -0400 "Ivan Vegvary" <ivanvegvary@gmail.com> wrote in message news:da0ebbe5-3ac9-4984-a366-4b350e9a7bb9@googlegroups.com... > Of course the only electronics in a 1948 auto is the ignition system. > Would love to look at 4 cylinders (8 total) at a time with the Rigol. > I do have inductive pickups that I can salvage from timing lights. For working around car ignition systems, I would look for one of the older tube type Tektronix models. Try 535, 545 for the large ones or a 453 with the nuvistor tubes in the vertical front end. These would survive better than a usual fet input amp. Just my 2 cents. |
| Ralph Mowery <rmowery28146@earthlink.net>: Oct 27 10:58AM -0400 In article <nuskhl$4m5$1@remote5bge0.ripco.com>, bje@ripco.com says... > a good set of ears and eyes will. > -bruce > bje@ripco.com I agree that unless there is some odd problem, just replace everything for a few dollars insted of maybe messing up a scope that is a thousand or so dollars. If there is an odd problem, maybe you could find someone that has one of the old Sun scopes. For the old cars just see if you can find a timming light and dwell meter. |
| Ralph Mowery <rmowery28146@earthlink.net>: Oct 27 02:28PM -0400 In article <98054939-face-498f-8e94-20dcb3f3e9c3@googlegroups.com>, jurb6006@gmail.com says... While I greatly prefer 1960s and 1970s cars it is still a good thing to keep that old beast running. > I drove a 1950 Chevy once, it was almost like work. People don't know how good they got it now. They have no idea what it means to double clutch, and they have no idea how undeveloped the steering and suspension was back then. Driving those old cars is almost like driving a semi truck, but the new ones aren't even that hard. > Well OK, it isn't really all that difficult but I bet you don't take that thing to work every day... My dad had a 1950 Chevy when I had my learners permit. Not too bad to drive. Even my mother drove that car. It even had the modern push button on the dash to start it. You did not need the key if you left the switch in just the off position. |
| Ralph Mowery <rmowery28146@earthlink.net>: Oct 29 01:58PM -0400 In article <nv1ukv$mvn$1@remote5bge0.ripco.com>, bje@ripco.com says... > Point is, it would be money more well spent just replacing all that compared > to doing whatever he wanted to do with the scope, which probably isn't going > to tell him anything. I have not had a car with points in it in many years so may be way off on the following. Wasn't the usual thing to change out the points, condenser, plugs and a few other things about every 10,000 miles or so back then ? Seems to me that the 3 or 4 cars I owned with the old nonelectronics in them needed to be worked on all most all the time. I remember replacing a lot of plugs and some points, distributer caps and wires. None of those had over 100,000 miles on them. Now lots of cars go 100,000 without anything but oil changes and tires. |
| Peter Easthope <petereasthope@gmail.com>: Nov 02 03:11AM -0700 On Tuesday, November 1, 2016 at 3:02:15 PM UTC-7, Andy Burns wrote: > It's perfectly normal to have a 3 pin plug on a 2 core flex to a lamp > ... unless the lamp has any metalwork, in which case it must be a 3 core > flex to earth that. OK, thanks. A Luxo L-1 lamp in Britain would have a three conductor flex. All such lamps I've seen in North America have flat two conductor lamp cord. The width fits closely in the square Luxo tubes. A L-1 in Britain has a round flex; correct? Thanks again, ... Peter E. |
| "pfjw@aol.com" <pfjw@aol.com>: Nov 02 04:05AM -0700 On Tuesday, November 1, 2016 at 6:02:15 PM UTC-4, Andy Burns wrote: > It's perfectly normal to have a 3 pin plug on a 2 core flex to a lamp > ... unless the lamp has any metalwork, in which case it must be a 3 core > flex to earth that. Try that in the US, and you would never pass UL (or CA in Canada). Betcha you would not get past Euro CE either. Peter Wieck Melrose Park, PA |
| Andy Burns <usenet@andyburns.uk>: Nov 02 11:07AM Peter Easthope wrote: > A Luxo L-1 lamp in Britain would have a three conductor flex. All > such lamps I've seen in North America have flat two conductor lamp > cord. The width fits closely in the square Luxo tubes. Don't know, I've hankered after one, but don't own one. > A L-1 in Britain has a round flex; correct? I notice the manual shows the double-insulated symbol, so 2-core flex could be used which would normally be flat, though you /can/ get round 2-core flex. While most UK plugs and sockets are BS-1363 square 3-pin, the older BS-546 round 3-pin plugs and sockets are still acceptable and available brand new. The even older BS-372 round 2-pin are marginally smaller and belong in museums, the same smaller spacing is used in BS-4573 plugs which are typically only seen in moulded-on versions, and exclusively used on shavers. Other than that, there are proprietary round 2 and 3-pin inline connectors not intended for plugging into wall sockets, which conform to the general BS-5733 safety standard, I use them on all my power tools, annoyingly these are similar but not mateable between manufacturers, e.g. <https://www.mkelectric.com/en-ar/Products/WD/PortablePower/duraplug/Leadconnectors/Pages/LCP102.aspx> |
| N_Cook <diverse@tcp.co.uk>: Nov 02 11:45AM On 01/11/2016 21:07, Peter Easthope wrote: > Does installation of a BS 1363 plug, with a ground pin, on a two conductor cord of a table lamp, violate wiring regulations? I don't imagine an unconnected ground pin posing a hazard. > Does a lamp in Britain ever have a cord with a ground conductor? > Thanks, ... Peter E. It depends on whether the handleable part of the lamp is metal or metal-finish, then must be grounded and whether there is a gooseneck or other movement containing the flex and therefore chaffing possibility . All quite sensible really |
| Andy Burns <usenet@andyburns.uk>: Nov 02 12:12PM > Try that in the US, and you would never pass UL (or CA in Canada). > Betcha you would not get past Euro CE either. I don't claim much knowledge of US power regulations, given you have separate NEMA 1-15P and NEMA 5-15P connectors, it probably makes sense to mandate that the former must use two conductor cables, and the latter must use three conductor cables. In the UK it's not as though the IET are lax on electrical standards, the fact is the only available 2-pin plugs nowadays are dedicated for shavers. For everything else there's no harm in having an unused earth pin, but (as Martin mentioned) a few devices use a plastic not-earth pin, which is necessary to open the shutters protecting live/neutral pins. |
| N_Cook <diverse@tcp.co.uk>: Oct 28 08:23AM +0100 On 27/10/2016 18:15, Jon Elson wrote: > Anyway, the pump bearings (water lubricated) are massively worn, and the > rotor eventually wore through the plastic housing. > Jon So like a smaller version of a central heating circulation pump, magneticc oupling through a membrane. At least washing m/c get used through the summer , so nver a chance to seize up |
| Jon Elson <elson@pico-systems.com>: Oct 29 03:16PM -0500 > Thanks for the motor update. I have been thinking about that motor and > why they would use it and it must be because shaded pole motors are so > inefficient. Right, it has to be fairly efficient as there is no fan. Since the rotor is in a sealed plastic housing, there is no external shaft to connect a fan to. That's probably why they cycle the pump on and off during drain/spin cycles. I guess the permanent magnet rotor is way more efficient than an induction rotor, too. The only tricky part is assuring the motor starts every time you apply power. Jon |
| Jon Elson <elson@pico-systems.com>: Oct 27 12:15PM -0500 There was a discussion a LONG time ago about a washing machine pump motor. I have a Kenmore Oasis washing machine that I've had to do some repairs on. The drain pump has gotten clogged a few times (coins, nylons) and I've been able to remove the clog and get it going again. I posted a partial description of the motor, because I couldn't quite understand it. Now that the pump has finally gone to complete failure, I was able to investigate further. So, it has a stator quite similar to a "phonograph motor" although there are no shaded poles, as I had expected. The rotor is a 2-pole ceramic magnet. The rotor runs in water, so there are really no seals required in the pump. When digging in deeper, I found there is a slip coupling between the motor rotor and the pump impeller, that allows the rotor to make almost one complete rotation before it grabs the impeller. I suspect this is to allow the rotor to vibrate wildly until it gets into sync with the mains frequency. AHH, and the pump is clearly designed to run in either direction! Now, it is all starting to make sense. The pump does make a rattling noise before it starts. Kind of ingenious design, probably had to make a BUNCH of prototypes before they got it to reliably start spinning. Anyway, the pump bearings (water lubricated) are massively worn, and the rotor eventually wore through the plastic housing. Jon |
| Sjouke Burry <burrynulnulfour@ppllaanneett.nnll>: Oct 27 11:57PM +0200 On 27.10.16 16:18, N_Cook wrote: > external emitter R,or is it just referring to doubling-up ? > datasheet > http://pdf1.alldatasheet.com/datasheet-pdf/view/38213/SANKEN/SAP15/+2732WUOYLI.OcU.utw+/datasheet.pdf "alldatasheet.com currently unavailable" GRRRRRR |
| N_Cook <diverse@tcp.co.uk>: Oct 27 03:18PM +0100 With the built in temp comp diodes, 1 silicon in the N type and 5 Schotky in the P and mirror-reversed pinning . Owner put a short across one speaker line, magic smoke but other channel is normal. Internal emitter resistor .22R of the p type is now not .22R. I intend removing both , of the failed channel , to check out of circuit, but anyone jumpered in an external .2R in these circumstances and no further problems from cracked die etc as this R is part of the die? The datasheet I think , in fractured English, says the thermal safe operating over-current zone, for the built in .22R is deliberately lower than the Darlington itself. Anyone ever disentangled the "English" referring to deliberately? destroying the internal R so as to use an external emitter R,or is it just referring to doubling-up ? datasheet http://pdf1.alldatasheet.com/datasheet-pdf/view/38213/SANKEN/SAP15/+2732WUOYLI.OcU.utw+/datasheet.pdf |
| "J.B. Wood" <arl_123234@hotmail.com>: Nov 02 06:22AM -0400 On 11/01/2016 06:01 PM, (PeteCresswell) wrote: >> Never had a Roomba but I'd'a hoped they had some way of like fencing rooms >> off with temporary guide slats. > If somebody came out with a "DeerBa" I'd pay at least a grand for it.... Hello, or maybe a mobile device that permanently dispatches other folks dogs that take a dump on your nice manicured lawn and the mess left by their onlooking owners. Sincerely, -- J. B. Wood e-mail: arl_123234@hotmail.com |
| "pfjw@aol.com" <pfjw@aol.com>: Nov 02 04:08AM -0700 On Tuesday, November 1, 2016 at 6:01:37 PM UTC-4, (PeteCresswell) wrote: > bumped on the shins by something hard would not be one of them. > -- > Pete Cresswell There is a device that does what you want, only it is movement operated. It sprays water (at as high a pressure as you can feed it) at anything that moves within 20 feet of it. https://jet.com/product/detail/86c7ca25b20a4721929026254c8d0fc2?jcmp=pla:ggl:gen_home_garden_a2:household_supplies_a2_other:na:PLA_348543420_24223148220_pla-161716964940:na:na:na:2&code=PLA15&ds_c=gen_home_garden_a2&ds_cid=&ds_ag=household_supplies_a2_other&product_id=86c7ca25b20a4721929026254c8d0fc2&product_partition_id=161716964940&gclid=CjwKEAjwnebABRCjpvr13dHL8DsSJABB-ILJCsvwhKGKbay20ZSeZwmLYc01dPB3w2cWJe0I8O9JRhoCcpTw_wcB&gclsrc=aw.ds One of many options. Peter Wieck Melrose Park, PA |
| Bill Moinihan <moi@example.com>: Nov 02 05:01AM Meanie wrote: > The lamps you have look like T12. That means, according to the LED info, > your LEDs will not reach the 50,000 hours because you are using T12 > ballasts. You are correct. All 16 of the 4-foot fluorescent bulbs said they were 40 watts, rapid start, average life 12,000 hours. https://s18.postimg.org/llp51oemh/01_all_bulbs_appear_to_be_40w_t12_bulbs.jpg Of the four ceiling mounted units, three worked fine either with four T12/40W fluorescent bulbs or with four T8 LED bulbs. https://s22.postimg.org/8hx6ech7l/03_4_t8_led_bulbs_work_just_fine.jpg The one ceiling unit that was humming badly had two ballasts inside when I removed the center covering steel plate: https://s13.postimg.org/kekhhvot3/04_two_T40_ballasts.jpg Both ballasts were of the same type, with a sticker on each saying Universal Therm-o-matic rapid start ballast For two F40W T12/RS lamps, high power factor Cat No 446-LR-TC-P, 120V, 60Hertz, 0.8Amp line Universal Mfg. Corp, Paterson NJ, Made in USA Class P Automatic resetting thermal protected https://s11.postimg.org/orqbysecj/02_the_ballast_is_40_W_T12.jpg Even though only one ballast is humming badly, I found the oddest situation when I put in either just one known-good fluorescent bulb or just 1 of the new LED bulbs. Only one lane worked with just one bulb, which was this lane, which I'll call lane 2 since it's the second one from the outside: https://s15.postimg.org/4gu6scm0r/a_lane2_is_working.jpg But when I put the single bulb in any other lane (leaving the rest of the lanes empty) the bulb didn't light up (whether it was fluorescent or LED). Is there any way to tell which two of the four lanes *each* ballast controls? Does the one good ballast control the two inside lanes? https://s17.postimg.org/tk1zfwckv/two_inside_lanes.jpg Or does one ballast control the two lanes next to each other? https://s16.postimg.org/uycmzw2wl/two_lanes_next_to_each_other.jpg Or does the one ballast control every other lane? https://s12.postimg.org/vqlyluwa5/every_other_lane.jpg |
| Meanie <meanie@gmail.com>: Nov 02 06:34AM -0400 On 11/2/2016 1:01 AM, Bill Moinihan wrote: > https://s16.postimg.org/uycmzw2wl/two_lanes_next_to_each_other.jpg > Or does the one ballast control every other lane? > https://s12.postimg.org/vqlyluwa5/every_other_lane.jpg A four lamp fixture with two ballasts will operate two lamps each. One will control the outer lamps and the other will control the inner lamps. To determine what ballast controls what lamps, you need to follow a wire to the tombstone (pin) connection of the lamp. For example, follow the yellow wire to one of the connectors. If it's the inner lamp, then that ballast controls those two lamps and the other will control the outer two. |
| John Doe <always.look@message.header>: Nov 02 01:59AM They only explode when they are poorly specked carelessly manufactured cheap shit made by slave labor in your communist country. -- "Mr. Man-wai Chang" <toylet.toylet gmail.com> wrote in news:nqchu2$l2t$1 dont-email.me: |
| Shadow <Sh@dow.br>: Nov 02 06:17AM -0200 On Tue, 1 Nov 2016 20:59:35 +0000 (UTC), >I can't believe how naive folks can be thinking that you can store >ANY energy and NOT have the possibility of an explosion. How right. And my wife's stink. Yesterday ... no I'll avoid talking about it. >Reagan Sorry to hear about that > BioStrategist Yeah, right. []'s -- Don't be evil - Google 2004 We have a new policy - Google 2012 |
| Poutnik <poutnik4nntp@gmail.com>: Nov 02 10:14AM +0100 On 11/02/2016 09:17 AM, Shadow wrote: >> ANY energy and NOT have the possibility of an explosion. > How right. And my wife's stink. Yesterday ... no I'll avoid talking > about it. Well, some people acumulating energy in form of beans really explode.. |
| Jeff Liebermann <jeffl@cruzio.com>: Nov 01 07:36PM -0700 On Tue, 1 Nov 2016 16:45:47 -0700, John Robertson <spam@flippers.com> wrote: >Indeed, easier to simply put a chain saw on a drone (really ducking!). >John :-#)# Done: <https://www.youtube.com/watch?v=6Viwwetf0gU> -- 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 |
| N_Cook <diverse@tcp.co.uk>: Nov 02 08:18AM On 01/11/2016 23:45, John Robertson wrote: >> I think the hassles getting aerospace clearance would make it uneconomic. > Indeed, easier to simply put a chain saw on a drone (really ducking!). > John :-#)# I would use a drone to loop a fishing line nylon, up around the tree at required height, and down . Use that to run a rope around the same path . Bang a good ground anchor in the ground and winch the top of the tree over. Then make some sort of running guide to fix a chain saw to a rope and pull that up the rope while it is running, while I'm standing well away of course. Require some extra ropery to get the angles and cutting progress though |
| Phil Allison <pallison49@gmail.com>: Nov 01 07:29PM -0700 Nucase Kook wrote: > thermometer was the 2 fuses, so something big presumably taking the > power. That with about .2 amp mains current draw, 5V ac over secondaries > and +/-1.8V on the DC rails ** Bet you have revered the positions of the PNP and NPN Darlingtons - causing the internal C-E diodes to conduct soon a power is applied. .... Phil |
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