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    Design new 0 to 30V power supply.

    I have a dual 36V, 4A PSU that can be used to simulate the transofrmer and PSU. However, we will be deviating from the idea of testing the whole prototype. Don't worry about testing, you have me willing to do it if noone else is keen, so I would tick that on your list. I would like to test the...
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    Design new 0 to 30V power supply.

    OK, 50mOhm is not tragic. I agree with standard components for this project. RC constant is the first thing that comes in mind here too. I dont think more than two settings will be needed, one slow and one very fast, so maybe a simple SPDT switch that connects a resistor in parallel will be...
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    Design new 0 to 30V power supply.

    What would you like to have tested Hero? I would like to see a setting for the attack time of the current limiter, a feature not found on cheap or DIY power supplies. 50 Ohm still sounds large to me, how about something in the 10's of milliohms range and a low input voltage offset differential...
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    The flashing Heart(i have some doughts)

    I think he means this one: http://www.electronics-lab.com/projects/games/001/ You build the project and give it your partner, batteries included! Hopefully they will appreciate your effort and think that you love them. You can then take it from there ;)
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    precision photoemission assessment.

    Your toilet fits the description :P On a different note, I don't think anyone here can readily help you with the theory behind your goo without pre-reading/research. If you can synth some goo, we can help you develop a conductivity meter.
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    precision photoemission assessment.

    I hate this about academic environments. Anyway, you could claim that a preliminary goo must be produced to verify the feasibility of a method to measure the conductivity of the goo.
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    analog ammeter

    Do you need a digital or analogue display paulhyi? What range of currents?
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    battery monitoring circuit

    Apart from agreeing with Hero's post have a look at these links: http://www.elecfree.com/Battery%20Monitor%20for%2012V.php http://www.electronics-lab.com/projects/automotive/009/index.html http://www.mhennessy3.f9.co.uk/battmon/index.htm You can also modify your circuit to use a duo-colour...
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    4W FM transmitter

    So similar... Thanks audioguru for pointing this out.
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    4W FM transmitter

    I used to build such kits since I was 10 back home in Greece. My first kit was this: http://www.smartkit.gr/details2.php?lang=1&wh=1&the1id=1&the2id=6&the3id=29&theid=29&open1=1&open2=6&open3=&thepid=122 A 555 based led flasher, which didn't work due to cold...
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    4W FM transmitter

    That circuit is part of this kit: http://www.smartkit.gr/details2.php?lang=2&wh=1&the1id=1&the2id=6&the3id=39&theid=39&open1=1&open2=6&open3=&thepid=206 and the text was originally in Greek. Anyway, you can have a look at the coils on that PCB, there is one...
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    Limiting Mains current.

    OK, here is a picture of the lot. Check your PMs for more info.
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    Anyone here na gumamit na ng RGB LED/White LED for color detection

    I have come across some integrated colour detectors, 3 photodiodes with a colour filter. I have never used them so I can't comment further. Here are some: http://au.farnell.com/jsp/search/browse.jsp?N=500001+1002850&Ntk=gensearch_001&Ntt=colour&Ntx=mode+matchallpartial They are...
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    Limiting Mains current.

    Your schematic looks OK. I think you can get away with increasing the value of R3 to a few kOhm unless your relay's coil draws something like 6W. What did you have in mind with D9? Is that there for protection? Finally, the zener diode at the gate of the IGBT. Maybe you dont need that if IC2...
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    precision photoemission assessment.

    You do not have current in your circuit as current flow would be a number of charged particles (electrons here) passing through a section of your material and having a common net direction. As I understand it, your electrons are bound in the material but not to a specific atom, much like a...
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    Please recommend a Good Electronics Book

    Hi Stuart and welcome to the forum. Thank you for your input. Your contact seems to be multidisciplinary so the book should be a good overview/introduction of/to electronics.
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    Brightest LEDs on the planet?

    And just to expand on Hero's post below, this is the topology of the ICs suggested earlier in this topic. You can google hysteretic LED driver for more info, Elektor Electronics (the magazine) published an article this year too. By adding a resistor in the LED's path you can sense it's current...
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    Please recommend a Good Electronics Book

    You dont need to know so much for a functional SSTC, but I like your mindset. In fact, if more people with your mindset entered higher eductation I believe the world would be a different place. This book: http://www.amazon.co.uk/gp/product/0471226939/ref=sib_rdr_dp is highly regarded in...
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    Brightest LEDs on the planet?

    No, no reason why you couldn't do that. But do you want to do that? Once the transistor is ON, your output will shoot to 12 V (assume car battery) and there is nothing you can do about it by changing the duty cycle. When the transistor is OFF your output volatge will fall depending on component...
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    Laser Sensor and Counter

    Yes, a 1MOhm resistor. Maybe you will have to tweak the value a bit. Ok, so no rule of thumb, read datasheet if available or test each LED experimentally.
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