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I just want to know if .001uF is the same thing as 1 nF. Thanks

Does anyone know what type of a component I can use for an inductance sensor (kind used in like automotive timing lights) I would like to generate a logic pulse per voltage pulse for use in a Basic stamp Tachometer for use on small engines. Will se up to absol. max 10,000 rpm's. Any body have any ideas. Otherwise does anyone have a good expanation of how a hall effect sensor works and if i could use it to send a pulse out as the magnet of the flywheel spins past the sensor. THanks all

Hi, I have a circuit that tries to run a solenoid by using a reed relay to connect the power. The circuit+relay works fine if I try and connect a motor, and the solenoid works fine if I just connect it direct to the power source. it seems like maybe my relay is switching on and off really fast instead of just staying on, does this seem possible and could it be the problem? any advice appreciated, Mark

hi everybody i just wanted to know what wattage soldering iron should be used for normal electronic works (P C B ). at present i have a jumbo size soldering iron which i use for electrical purposes which has a big tip. also is there any tip sizes (if at all there are) for soldering iron to be used for P C B because the one i have is a bit too big for P C B (thats what i think). aditya n

hi everybody i just wanted to know what wattage soldering iron should be used for normal electronic works (P C B ). at present i have a jumbo size soldering iron which i use for electrical purposes which has a big tip. also is there any tip sizes (if at all there are) for soldering iron to be used for P C B because the one i have is a bit too big for P C B (thats what i think). aditya n

adityan007@... wrote: Hi Aditya, ????????????????????? There is no easy answer to this question, it depends entirly on what you intend to solder. How ever for the average hobiest, I would sugest something in around the 60 to 100 Watt range as far as power is conserned. Dependant upon which type of iron you buy there will be a huge range of soldering iron tips. Which one you select will be nearly entirely personal preferance. Three coman tip shapes are: Chisel, Pointy, and flat. I personally prefer Chisel, around 2 to 5 mm at the tip. But this is becuase I do alot of surface mount rework as a job.??? Cost is also an important factor. No use dreaming about that $1000 dollar soldering iron with all the great themo controls and fancy tips if you dont have the money. Personally, I started off with a 200 watt Berko Iron with a 15mm tip 2mm diameter solder, and bakers flux. And yes I soldered PCBs with it. Now however I use a Weller TC-202 60W iron, with a variaty of tips. This is more than adequate for my curent use. As an obsevration. I've been soldering for around thirty years now, and in my experiance, practice is what counts rather than the tool. I have seen some super educated people make a total mess with some really great tools, and my wife is capable of doing some of the best most consistant work I have ever seen with some real shit equipment (not mine) and no formal training. ????????????????????? I feel the best advice I can give you however is test a few diferant types of irons before you settle or buy one for yourself. If you have friends with soldering irons, use thiers for a few hours if possible. Does it suit your hand?? Can you make a good joint on a variaty of pads?? Desolder using some desolder briad, How easy is it????? Does it do a good job with ease?? How easy are the tips to change?? If possible experiment with differant tips, and solder. If it's a thermostat type, (Adjustable) how easy is it to adjust?? Do you like the controls?? You will hear all sorts of advice from all sorts of people as to what the "Perfect iron"??? might be. However, largly I think is is personal choice. Dont be afraid to try a few things out. ??? -- )O(??? )O(??? )O(??? )O(??? )O(??? )O(??? )O(??? )O(??? )O(??? )O(??? )O(??? )O(??? )O(??? )O( ???????????? The Sinister Dragon ??? Hey, Just because I'm EVIL, ???????????? Doesn't make me a bad person......????????? >:-) Visit My sites at Geocities: ??? Blood Moon - http://www.geocities.com/evil_trinity666/index.html ??? Little Herbal - http://www.geocities.com/tanacetum_vulgare/index.html ??? Zenit Photographic - http://www.geocities.com/zenit_em/index.htm Join my Egroup: ??? Inverted Pentagram - http://Groups.yahoo.com/group/Inverted_Pentagram ??? Zenit-EM - http://groups.yahoo.com/group/Zenit-EM ???

Something cute that I found... It may or may not be off topic. The Sex life of an Electron by Eddie Currents One night when his charge was pretty high, Micro-Farad decided to seek out a cute little coil to help him discharge. He picked up Milli-Amp and took her for a ride in his Megacycle. They rode across the Wheatstone Bridge and stopped by a Magnetic field with flowing currents and frolicked in the sine waves. Micro-Farad, attracted by Millie-Amp's characterisic curves soon had her fully charged and proceeded to excite her resistance to a minimum. He gently laid her at ground potential, raised her frequency and lowered her reluctance. With a quick arc, he pulled out his high voltage probe and inserted it in her socket, connecting them in parallel. He slowly began short circuiting her resistance shunt while quickly raising her thermal conductance level to mil-spec. Fully excited, Milli- Amp mumbled "MHO...MHO...MHO" With his tube operating well into class C, and her field vibrating with his current flow, a corona formed which instantly caused her shunt to overheat just at the point when Micro-Farad rapidly discharged and drained off every electron into her grid. They fluxed all night trying various connectors and sockets untill his magnet had a soft core and lost all of its field strength. Afterwards, Milli-Amp tried self-induction and damaged her solenoids and with his battery fully discharged, Micro-Farad was unable to excite his field. Not ready to be quiescent, they spent the rest of the evening reversing polarity and blowing each others fuses. BUT WAIT!!! Theres M O R E ! Micro was a real-time operator and dedicated multi-user. His broad-band protocol made it easy for him to interface with numerous input/output devices, even if it meant time-sharing. One evening he arrived home just as the Sun was crashing, and had parked his Motorola 68000 in the main drive (he had missed the S100 bus that morning), when he noticed an elegant piece of liveware admiring the daisy wheels in his garden. He thought to himself, "She looks user-friendly. I'll see if she'd like an update tonight." Mini was her name. She was delightfully engineered with eyes like COBOL and a Prime mainframe architecture that set Micro's peripherals networking all over the place. He browsed over to her casually, admiring the power of her twin, 32-bit floating point processors and enquired, "How are you, Honeywell?" "Yes, I am well," she responded, batting her optical fibers engagingly and smoothing her console over her curvilinear functions. Micro settled for a straight line approximation. "I'm stand-alone tonight," he said. "How about computing a vector to my base address? I'll output a byte to eat, and maybe we could get offset later on." Mini ran a priority process for 2.6 milliseconds then transmitted 8K. "I've been dumped myself recently, and a new page is just what I need to refresh my disks. I'll park my machine cycle in your background and meet you inside." She walked off, leaving Micro admiring her solenoids and thinking, "Wow, what a global variable. I wonder if she'd like my firmware?" They sat down at the process table to a top of form feed of fiche and chips and a bucket of Baudot. Mini was in conversational mode and expanded on ambiguous arguments while Micro gave occasional acknowledgments, although in reality he was anyalyzing the shortest and least critical path to her entry point. He finally settled on the old,'Would you like to see my benchmark routine?' but Mini was again one step ahead. Suddenly she was up and stripping off her parity bits to reveal the full functionality of her operating system software. "Let's get BASIC, you RAM," she said. Micro was loaded by this stage, but his hardware policing module had a processor of its own and was in danger of overflowing its output buffer, a hangup that Micro had consulted his analyst about. "Core," was all he could say, as she prepared to log him off. Micro soon recovered, however, when Mini went down on the DEC and opened her divide files to reveal her data set ready. He accessed his fully packed root device and was just about to start pushing into her CPU stack, when she attempted an escape sequence. "No, no!" she cried. "You're not shielded!" "Reset, baby," he replied, "I've been debugged." "But I haven't got my current loop enabled, and I can't support child processes," she protested. "Don't run away," he said, "I'll generate an interrupt." "No, that's too error prone, and I can't abort because of my design philosophy." Micro was locked in by this stage, though, and could not be turned off. But Mini soon stopped his thrashing by introducing a voltage spike into his main supply, whereupon he fell over with a head crash and went to sleep. "Computers!" she thought as she compiled herself. "All they ever think about is hex." _________________________________________________________ Do You Yahoo!? Get your free @yahoo.com address at http://mail.yahoo.com

----- Original Message ----- From: budijanto setijoso To: mixmaster mixingTechnical Audio Sent: Sunday, July 15, 2001 9:42 AM Subject: your comment Hi Guys, After joining for several months, I decided to introduce myself to this enjoinable and pleasant GROUP. I do alot of repairing Professional Audio Gear, thatswhy i have a lot of audio gear, that could probably still in used, maybe some already a vintage gear. I build also my Home Page: www.geocities.com/absolute_sound to put all the audio gear. I like to hear any criticism and suggestion, but hoping to improve in future. Thanks n regards, Budijanto S

I just want to know how you go about building a homemade transformer. Thanks

Is there some way to filter this spam crap from the list?

Hi Everyone! I am going to be relaunching StuckButton magazine on September 1. Most of you know it, others won't - basically its a free magazine (now) centered around any aspect of radio, electronics, telecommunications and computing (well the technical (hardware) and software fix side of computers anyway). I'm looking for articles for the new bi-monthly magazine (now 60 pages, looks much more like a magazine should!). So if you want to write about any of the above topics I've mentioned above (or anything else related - just ask me), send a note to stuckbutton@... I want as many articles as possible to keep a good collection, which I will use as desired in certain issues (if not the first, maybe the second - it'll get there!!!!). I won't be able to pay you anything (it's a free magazine anyway!), but you will get all the credit you deserve! Photos, circuits, diagrams, cartoons, URLs, history, equipment reviews, news items and "info snippets" etc are great also! You can find it at: http://www.yahoogroups.com/group/stuckbutton Thanks, Dan Bartlett StuckButton Editor-In-Chief

I know that people may criticize me for asking for help on this but I am not an Electronics expert... yet. And furthermore I don't believe in free energy. :) I have a final project coming up for my electronics class and the proffesor says that we have to build something that requires sautering... it doesn't even have to be breadboard. This project is just for fun because my college requires a final project but my prof. likes to base it all on a final, So the finished project does not have to work. With those criteria in mind i though building some type perpetual motion machine might be fun. In researching on the net I found the easiest looking one (ie. cheapest) was http://www.icehouse.net/john1/foreward.html The plans are very sparse for this machine though. In your profesional opinions is this just a hoax becasue the plans are so nonspecific? thanks, awzse _________________________________________________________ Do You Yahoo!? Get your free @yahoo.com address at http://mail.yahoo.com

Has anyone noticed that wirewound chokes have all but disappeared from the electronic suppliers lists these days? The omission of these and certain other items with which I was once familiar, and the appearance of new components like IC voltage regulators, is very disconcerting to me, as I learned my electronics in the late 1940s and early 1950s (before transistors) when I studied for Physics A level and the Amateur Radio City and Guilds Institute Exam. I recently attempted to build a small power unit with a voltage regulated smoothed output of 12V for a model railway, but couldn't get the bl***y thing to work. However, once I had swapped the reg. for a small transformer wired with half the secondary winding as a choke, (Pi smoothing circuitry) I managed to obtain the results expected. I would certainly not mind a simple discussion of the _practical_ intricacies of transistor or IC circuitry, as probably the more times one has the chance to absorb ideas the better will become one's understanding. For Info, my present interest in electronics is mostly concerned with model railways: PSUs, Controllers for special purposes, LED projects - lighting, miniature signs, etc., Signalling (automatic), Turntable and Level Crossing electro-mechanical operation, Solenoids. I am having a problem with a turntable circuit at present. I need a double pole change over relay which will operate at circa 6V, _without chatter_, so that I can latch it with contacts 'on' until the latching (solenoid) circuit is broken elsewhere and thus reset. Can anyone suggest a likely type or source? What are the relative merits/demerits of including fuses in both the line and neutral mains feed to a PSU and also in the +ve and -ve O/P? I have fitted a Mains - 12VDC PSU in this way (with fuses in both) but am having second thoughts about the safety of this arrangement if the fuse in the neutral, or fuse in the -ve O/P should blow without corresponding breaks in the other fuses.? Keith Messent, Skipton, UK ----- Original Message ----- From: Ralph Krumdieck <ralphkru@...> To: <Electronics_101@...> Sent: Thursday, 19 July, 2001 04:03 PM Subject: Re: [Electronics_101] Your friendly Moderator.... > > > One question I have for you all is: What level of electronics > >are people on the list up to?? I would like to start posting some info > >now that we have some members, But need to know where to start. Can I > >assume that we all know the basics??

hi thats very good....as a response i will say that there should be more of practical things like simple interesting circuits which can be made easily(i mean that the components should be available easily) and also problems and other things(like reading a data sheet,understanding the component numbering like 1N1007,741 etc) which arise in practical circuits which are not given in textbooks. text books no matter how good they are cant replace practical experince....u see. of course theory should be also be there but personally i am feed up with it (doing a 4 year degree course in electronics and telecom). aditya n

hi i just got a idea yesterday and here it is. normally we charge batteries in series i.e if we want to charge 2 batteries of 1.5 v then we connect them is series and apply 3 v and so on..changing the voltages...as the no. of batteries increase. but cant we charge them in parallel i.e connect all the batteries in parallel and then apply 1.5 volts. is configuration will require only 1.5 volts no matter how many battries are charged at a time. can this idea work. please reply . thanks. aditya n

A quick rant from your freindly moderator, ????????? Just a question asked on another list that I am on, and a quick reply. I'm posting this for the "Beginers" on the list so those of us that know everything can of course instantly delete this post and go on with our perfect lives. ??? ???>> What is the sponge used for, I have seen people wipe the tip before ???>> and after they use it on a wet sponge? ??? ????????? The sponge is used to clean the tip between soldering. When the Iron has been standing for any period of time wilst on, a layer of oxides will form on the tip. Also, any flux remaining on the tip will deteriate. It is important to remove these before the next use as it will contaminate the joint. Just to put this into percpective. This will perhaps have little affect on a "Tandy" flashing light kit, that you can resolder if the joint goes bad, but might break things if the aircraft's computer dies. In any case I tend to have the habit of wiping my tip clean before use whenever I'm soldering, as it is not a bad one, and though the telecomunications equipment I work on isn't going to kill anyone if a "bad" joint has problems, it does affect the reliabillty. ????????? Just a few words about using sponges to clean: ????????????????????? Firstly, it is a VERY comman error for people to have WAY to much water in the sponge. If you can wring water out of the sponge you are using then there is WAY to much in it. When you hear of people talking about damp sponges they mean DAMP. If you have to much water in the sponge, when the tip touchs the sponge, it imediatly cools to below the melting point of the solder, thus effectivly making it imposible to remove the oxidized solder, and potentially making the next joint soldered cold. This especially happens when the tip is long and narrow. Sure, you have to re wet the sponge after a couple of hours, but this is really isn't going to hurt you now is it?? ????????????????????? Second, I have seen some REALLY discustingly filthy sponges in my time. Your sponge should be cleaned, thoughly rinsed under fresh water before each use. (Be carefull not??? to let scrap solder go down the drain, it contains lead don't forget) Otherwise when you wipe the tip. you end up puting more dirt on it than you are removing. It takes about a whole minute to do this not a lot of time in the grand scale of things, and no time at all compared to the time it can take to find a dodgy joint in that prized project you've been working on for weeks that now doesn't work. ????????????????????? Likewise I have seen sponges used WAY past their sensible used by date. A sponge costs what, a dollar?? So why use some ratty, dog chewed peice of crap that you wouldn't normally think twice about throwing away?? If it starts wearing out replace it for the above reasons. ????????????????????? One final piece of advice, is only to use sponges designed for the purpous. I dont know how true or false the info is, but sponges for this use are suposed to have been designed to drag a hot iron across. They can stand the heat, and suposedly have no funny additives. I do know there are quite a few varities of synthetic sponge around. Alot of these have additives to help with cleaning kitchen surfaces, and they may have low melting points. These sponges will once again contaminate the tip. In any case once again the proper thing just ain't that expensive, so why take the risk. ????????? O.K. my rant is now over, I can't believe I wrote so much about tip cleaning sponges. Maybe I need a life or something. In any case, I hope the info was helpfull to our beginers....... )O(??? )O(??? )O(??? )O(??? )O(??? )O(??? )O(??? )O(??? )O(??? )O(??? )O(??? )O(??? )O(??? )O( ???????????? The Sinister Dragon ??? Hey, Just because I'm EVIL, ???????????? Doesn't make me a bad person......????????? >:-) ??? ???

Can someone explain the basics of a hall effec sensor to me? I believe if I understand correctly that they sense changes in magnetic fields. Is that correct? If so are they sensitive enough to sense the magnetic field that is produced by a wire that has been energized. If not what sensor should I use for this type of application. I am wanting to sense when a spark plug wire on a small engine is firing and then send that back to a F-V for a read-out. Thanks

Hello everybody. I recently put together a small solar powered project. It draws about 300ma at a regulated 5v. It runs great here in LA, but now I want to bring it to London. Obviously I'm going to be getting a lot less power out of my panel. What I want to do now is attach a 12v lead acid battery that can power the project when the sun is behind the clouds (hopefully not all the time!). Is it complicated to power a circuit and charge the battery at the same time? Should I try and find an off the shelf solution to this problem, or is this something I can put together myself (with some help from the list)? Any advice greatly appreciated. Mark Allen

O.K., For those of you who are beginers, you may find some interesting info at: ????????????????????? http://www.rayvaughan.com/kit.htm There is some basic kit building info for those who are starting out. For those of you who are into something a bit more deeper, Ray seems to be into ameture radio, and has quite a bit on his site about this, plus a bit of other stuff you might find interesting. Check it out at: ????????????????????? http://www.rayvaughan.com/index.htm If anyone else has any non comercial Electronics sites they wish to tell us all about feel free to send the URL to the group. TAKE NOTE though, NON-Comercial. If you have any questions about wether a site qualifies as non-comercial, send me (the moderator) the URL off list, and I will asses it. ??? )O(??? )O(??? )O(??? )O(??? )O(??? )O(??? )O(??? )O(??? )O(??? )O(??? )O(??? )O(??? )O(??? )O( ???????????? The Sinister Dragon ??? Hey, Just because I'm EVIL, ???????????? Doesn't make me a bad person......????????? >:-) Visit My sites at Geocities: ??? Blood Moon - http://www.geocities.com/evil_trinity666/index.html ??? Little Herbal - http://www.geocities.com/tanacetum_vulgare/index.html ??? Zenit Photographic - http://www.geocities.com/zenit_em/index.htm Join my Egroup: ??? Inverted Pentagram - http://Groups.yahoo.com/group/Inverted_Pentagram ??? Zenit-EM - http://groups.yahoo.com/group/Zenit-EM ???

Just for our beginners, Here is some basic information on ohms law, and resistance calculations. I hope they are helpful. I'm starting here as I don't know what you all know in the way of electronics, and I hope to be able to advance to some more complicated information, such as amplifiers and digital stuff. However I want to establish a base line first. So if this is a bit basic for you, wait, I hope I'll eventually get to something that will interest you a bit more....... Above, is about the most fundamental electronic circuit you will ever encounter. When it comes down to it nearly all electronic circuits can be expressed in this form or similar. Basically, you have a power source, and a load. In this case the power source is a twelve volt battery, and the load is a 1200 ohm resister, or a 1.2 kilo ohm resistor expressed as 1k2. Though the above circuit taken in it's literal form is not very useful, other than to flatten the battery, is serves as a basic platform for discussion into Ohms law. Lets assume that the above battery for instance can deliver a 1 amp current for 1 hour before it flattens. So how long will it take the battery to flatten in the above circuit?? This can be very easily calculated using a bit of common sense and Ohms law. Basically, Ohms law states: Current flowing in a resistor (or Conductor) is proportional to the supplied voltage, and inversely proportional to the resistance. Just what the hell does this mean exactly?? It means, that what ever you do to the voltage, will happen to the current. so for the same resistance, if you double the voltage, the current will double. That covers the first part of the law, now the next bit. Assuming you have a fixed voltage and start playing with the resistance, what happens to the current?? What happens when you increase the resistance, is that the current is divided by the same amount as the resistance is increased. For example, if you double the resistance, you divide the current by two, or halve it. If you triple resistance, you divide the current by three, and so on. Very soon you will be able to demonstrate this with ohms law yourself, but for now just trust me. In any case, we come to how this law is applied in the real world. In the above circuit, we know the applied voltage is 12V. We know that the circuit resistance is 1200 ohms. Now using the formula below, we can calculate the current: Lets do the current calculation for our little problem....... So we now know how many amps are running through our little circuit, 0.01 Amps, or to express it another way ten thousands of an Amp, or more commonly 10 milliamps. Now, just a small side step from the ohms law issue, we know our battery can deliver 1 Amp for 1 hr. In theory that means it can deliver 0.1 Amps for ten hours. By extension I'm sure you can see that it will hopefully be able to, in theory at least be able to deliver 0.01A (10 milliamps) for 100 hr. Things in real life are actually just a bit more complicated than this. As the power in a battery is used, it generates internal resistance, which affects it's ability to supply a fixed voltage and current. A fair amount of sophisticated chemistry and internal mechanical design goes into preventing this happening by battery manufacturers. However it serves as a general rule of thumb for calculating how long a given battery will supply the necessary power to a circuit. With our calculated current now placed in the circuit, we now have the below information: Just a bit of further information: Just what is current?? Current as we all know is the flow of electrons through a circuit. To be precise, One Ampere is the rate of flow of electric charge (electric Current) when one coulomb of charge passes a set point in one second. One Coulomb equals the charge in 6.24X10^18 electrons. So for those of you not familiar with this notation, that is 6,240,000,000,000,000,000 Electrons flowing past a fixed point in one second equals one Ampere. When we calculate the amount of current flowing in a circuit, we talk about electrons as if they have are moving in a specific direction. Now just what direction do electrons travel around the circuit. Back in the days when Electronics was in it's beginnings, it was believed that electrons carried a POSITIVE charge, and for various then observable reasons it was decided that electron flow from the positive terminal, through the circuit, to the negative terminal. This is termed CONVENTIONAL current flow, and is used in nearly all electronic calculation, unless specifically stated otherwise. As is now known, however, Electrons are negative and travel from the negative terminal through the circuit and to the Positive terminal. This is called ELECTRON flow. UNLESS SPECIFICALLY STATED, we will ALWAYS be referring to Conventional flow when we do our calculations. For those of you who are still awake and haven't just deleted this little lesson, here are some simple examples for you to practice with. I'll post the solutions in the next couple of days: Remember that 2k5 = 2500 ohms, and 100R = 100 ohms. It a good idea to try and get familiar with this notation, as it is used fairly regularly through out modern electronics. I'll post the solution to these problems in the next week or so, and then we will have a look at what happens when we have more than one resistor in our little circuit. check out the two circuits below: How do we figure out the current flow?? We'll deal with it in the next week or so......... )O( )O( )O( )O( )O( )O( )O( )O( )O( )O( )O( )O( )O( )O( The Sinister Dragon Hey, Just because I'm EVIL, Doesn't make me a bad person...... >:-) Visit My sites at Geocities: Blood Moon - http://www.geocities.com/evil_trinity666/index.html Little Herbal - http://www.geocities.com/tanacetum_vulgare/index.html Zenit Photographic - http://www.geocities.com/zenit_em/index.htm Join my Egroup: Inverted Pentagram - http://Groups.yahoo.com/group/Inverted_Pentagram Zenit-EM - http://groups.yahoo.com/group/Zenit-EM