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  1. C

    3W solar garden light help.

    I concur with Alec t, a Sealed Lead Acid battery. The advantage of the lithium family of batteries (and most others) is the smaller size and lighter weight of a given capacity, neither of which matter in a fixed location. One advantage of an SLA battery is that it's easy to charge--low voltage...
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    How much of a Short circuit is too much?

    Soma, I'm still waiting for your answer: Do you want to modify the schematic as you posted it in the OP, with one 12VDC source (presumably a battery) powering everything? ( A 3V two-AA battery will not power your receiver and relay.) Or are you planning to change the diagram and use a separate...
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    How much of a Short circuit is too much?

    Okay, I'm puzzled. :confused: Your schematic shows your circuit using ONE power source, presumably a battery, to power both the RF receiver-relay module and the heater/igniter nichrome element. But you mention planning to use 2 AA cells. If you're talking about alkaline batteries, 2 AA cells...
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    How much of a Short circuit is too much?

    You can't really do that with nichrome heating wire. Its cold (room temp) resistance will increase dramatically when it heats up. All metals develop higher resistance when heated, so its resistance in use is a function of how hot it is, which in turn is a function of how much current it's...
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    House circuit security?

    Glad I could help. I've had to operate in a few foreign languages myself and I know how difficult it can be to find a word that's not used in normal "socializing" language. A few years ago, I was in Costa Rica and needed to buy a soldering iron downtown (without access to Google Translate)--I've...
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    House circuit security?

    I'm with *steve* on one point: If you don't have a good understanding of mains power wiring, you shouldn't be working with it. But you might have a way to plug a module into your outlet, without messing with the mains wiring. Most homes in North America now have circuit breakers instead of...
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    Connecting 2 PIR security senser together

    Photos are nice, but details such as the make and model number of the control panel and PIR are even better. If you're using mainstream equipment, chances are good that we'll be able to Google up the installation manuals ourselves. (If you're using cheap Chinese off-brand junk from eBay...
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    Solar powered balloon?

    Cjdelphi, what size balloon were you envisioning? One of the reasons we aren't already doing this is the size scale involved in ballooning. By the time you get balloons large enough to lift motors, batteries, control circuitry and cameras, the balloon is large enough to catch and be carried off...
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    Unknown Part

    Some transformers have fuses on the secondary side. That would explain the zero-resistance.
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    how pir sensor works?

    Is this a PIR motion sensor? If it is, you can usually find a brand name and model number on it, which would make it a lot easier to answer your question. There are a lot of PIR motion sensor models out there, and significant differences between them. If you can't find a model number, do you...
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    Alarm Dual Beam Photoelectric Infrared Detector

    By "toggle switch", do you mean the alarm relay contacts? The relay contacts themselves do the same thing, but without a schematic, we don't know how the wire terminals are wired to the relay contacts and tamper switch. On some devices, the connection between relay contacts and tamper switch is...
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    Alarm Dual Beam Photoelectric Infrared Detector

    Before you finally give up on it...Some of those tamper circuits can be trickier than you'd think. Rather than just jump out the terminals (if that's what you did), try closing up the housing before testing and see if that makes a difference.
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    Series Tieing Lithium Ions PROBLEM HELP

    Well, this does seem kind of obvious, but somebody's gotta say it: When you connected the cells together in series, did you connect positive to positive or negative to negative; (instead of [+] to [-])? So that the two potentials oppose each other and cancel each other out? 'Cause I can't see...
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    Powering an old smoke detector

    Gee, your radioactive doorbell looks an awful lot like an ionization-type smoke alarm with a speck of americium at its core. But if you want to wire 120VAC into it, I don't see why you can't wire it as a doorbell. You only need one set of white & black to power it up--the other pair is to...
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    Light Bulb Technology?

    I thought I'd bring Osmium's post #9 back up because it appeared that everybody, so far, who posted after him/her either didn't bother to follow the link, or ignored it. This is recent new in the field of electrical lighting and to me it looks plausible that incandescent lights are still in the...
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    Infrared sensors help please

    That might be theoretically possible, but highly unlikely. Eyelids (or any human skin) aren't particularly IR-reflective. IR is heat, and skin tends to absorb heat rather than reflect it. Aside from that, eyes and lids already emit more than enough IR/heat to be detected in patterns and...
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    Infrared sensors help please

    Well, there are two choices in IR sensing: They're Passive InfraRed sensors, or Active InfraRed sensor assemblies. The sensor assemblies of Passives or Actives are different. Active IR assemblies don't detect "motion" per se, they detect loss of the active beam (such as something blocking the...
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    Infrared sensors help please

    I've been working with passive infrared (PIR) motion sensors for decades. The only thing you need to understand is that they're passive. They don't emit any form of radiation whatsoever. The PIR sensors detect the infrared (heat) being emitted by whatever they're watching. So no, there is...
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    Run a submersible pump on battery ?

    Oops, my bad. I navigated to eBay through the Shieldlab site to those first two links: Not the way to do that. Sorry. The 3rd and 4th links connect you okay. 1st link for AD12612 power supply on eBay : http://www.ebay.com/sch/i.html?_from=R40&_sacat=0&_nkw=AD12612&_sop=15 This listing contains...
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    Motion Detection

    Mike, this is one of those cases where it would be helpful if you could tell us the application of the motion sensor you're looking for. For example, is this for intrusion detection? Or to annunciate when someone walks into your shop? Or detect a car that has come into your driveway? Or detect...
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