Hero999

Lithium Polymer is just a variation on Lithium ion their chemistries and charging regimes are identical. To be picky, according to Wikipedia, your battery is not a lithium polymer but a lithium-ion polymer because a lithium polymer cells need only work when heated above 50

You need to learn how to use Google, I found the following in a few seconds. http://www.google.co.uk/search?hl=en&client=firefox-a&rls=org.mozilla:en-GB:official&hs=N1W&ei=KfUYS8OvH4604QbiwKn3Ag&sa=X&oi=spell&resnum=0&ct=result&cd=1&ved=0CAgQBSgA&q=PIC+tutorial&spell=1 http://www.winpicprog.co.uk/pic_tutorial.htm http://www.gooligum.com.au/tut_baseline.html

What are you trying to do? It's pretty easy to build an h-bridge with relays or a mechanical switch and virtually no electronics knowledge or soldering. If all you need to do is reverse a motor then it's the best solution. If you need to do something more complicated such as motor speed control, you can buy pre-assembled motor controller boards.

Care to mention what the budget limit is? It's possible that buying a power meter is the cheapest solution.

Is the negative rail of the DC power supplies connected to earth? I take it the neutral is earthed? Please provide more information: how do the control boards connect to the motor? Is there any isolation between the AC and DC supplies?

As a general rule of thumb, Li-ion batteries should be charged at no more than 0.5C. In this case, the instructions clearly state that it can be safely charged at 1C which is 800mA in this case to you can use the 600mA charger after all. This is no surprise; some of the smaller and more modern Li-ion batteries can be safely charged at higher currents than 0.5C which is what you should assume in the absence of any information.

You need a power meter. You can buy meters that give you the current drawn, the actual power, the VA and the power factor. Assuming the motor is inductive, these figures can be used to calculate the inductance and resistance of the motor whilst it is running.

Repeatedly bumping a thread is not going to increase the chances of you getting help: be patient, it often takes a couple of days before someone that knows the answer to drop by. The chances are no one has responded because you didn't provide enough information so if you must bump a thread then append more information and you might have get help. I have a couple of basic ideas but there's no point in me posting them because I don't know they're suitable, unless you provide more information.

Generally no. Look at the datasheet and note the luminous intensity figures. The viewing angle is also important, some LEDs are very bright but have a very narrow beam width and appear unlit unless you're looking directly at them. That depends on how powerful the battery is. That depends on whether the magets are strong enough to activate the reed switches or hall effect seonsors.

Small lithium batteries don't need a series resistor to power an LED because they already have a high internal resistance which limits the current. For a circuit that will power white, blue or violet LEDs from a 1.5V cell Google for Joule thief, although you might need to modify it slightly to power it from a 3V battery. There are other questions you need to ask yourself: Does it need to be waterproof? How long do you want the battery to last for? Do you want the battery to be easily replaceable or is this just a single use item?

I don't know, I've not had much real life experience with anti-shoplifting devices. I know how they work but wouldn't be able to tell you whether they're fast enough. Why don't you do some research and ask a manufacturer of an anti-shoplifting system?

Assume four step gain control refers to the gain select pins which can select gains of 20, 26, 32 or 36dB. A volume control can be added to this circuit using a potentiometer as with any other audio amplifier.

Ever tried DigiKey? I don't live in the US so I don't really know but many people on the Internet speak highly of DigiKey.

If you use logic level MOSFETs for the low side then you won't need to perform any level shifting because they will be able to conduct the full current with 5V at the gate.

It looks like you can just leave the negative outputs unconnected.

Care to post a schematic? It sounds like you're having difficulties interfacing the AC circuit with the DC control side. How are you ensuring there's adequate isolation between the AC and DC circuits?

No, you clearly don't understand how the circuit works. What voltage is driving the low site MOSFETs? I assume it's 5V so why do you need 10V zeners to protect it? Why do the zeners need to be bidirectional when the gate voltage can only be one polarity? The high side MOSFETs are connected backwards.

What are you trying to monitor?

Short of using a complex image recognition system the only way to distinguish the ball from the goal keeper is to tag the ball in a similar manner to how goods are often tagged to tackle shoplifting. The trouble is I'm not aware of any anti-shoplifting system fast and accurate enough to be used for this.

That's not always true. It depends on the MOSFET and the IGBT, as I said before, for devices with higher voltage ratings IGBTs are best but for low voltage devices MOSFETs are much better. If you're going to use zeners then you might as well replace R1 and R3 with zener diodes to limit the gate voltages to a safe level. It's still a good idea to put a resistor in parallel with the zeners, to alow the gate capacitance to discharge, but it's value is much less critical than for a potential divider.

Yes.

You could use a micro-controller with an ADC to display the reading on an LCD. It depends on how accurate you want it to be: a pot will have a typical linearity of 1% which is an error of 2.7

It should work.

Heat loss is power which is not converted to electrical energy. Calculate the thermal power in, calculate the electrical power out and work out the efficiency.

A 20W amplifier can be used to power 60W speakers providing they have an equal or higher impedance than the speakers the amplifier is designed to drive. For example a 4Ω 20W amplifier can drive 8Ω 60W speakers but it can't drive 2Ω speakers.