WoW! I am so impressed with everyone's enthusiasm with this project. And with any project there are always a ton of questions in the discovery process. I have tried to compile the most asked questions so far. Please feel free to ask you own questions.
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Q :What does a condenser do?
A : In electronic circuits, a former name for a capacitor.
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Q : The use of that specific relay in the circuit is accidental or is there a reason for that specific one?
Could we use any mini or non-mini relay for that matter? Is there a reason to even use a relay and could we just replace this with solid state?
A : The relay is the one that Peter Lindemann used and is widely available. The one I originally used was from the 70's. and is no longer available and the one from the 70's drew the least amount of current. but the one from radioshack was the mostly closed match. You can use any relay you want as long as the contacts can handle it, and the coil current draw doesnt matter you. Remember you are trying to impedance match the primary and the coil on the relay, the better the impedance match the lower the current draw, but you can use whatever one you want, your batteries might not last as long, and you can also use larger batteries. There is energy recovery on it. The first one i did i ran 72 hours straight and it did not run down the batteries but because the extremely high voltage the light output on the very first 9 watt cfl had diminished light output prematurely. So matching the bulb is also important. Its all a journey and a experiment. the bulbs are cheap, the relays are cheap and the coils arent that expensive either. Through experimentation im sure you will find the perfect match and possibly be able to light the 4 foot regular magnetic ballast fluorescent bulbs if you get the proper match.
You do not have to use a relay I used it for simplicity. You can use a 3055 transistor in self oscillation mode but you would have to use a heat sink and the current draw would be much higher, 555 timer and a FET, you can use a SCR. you can use a small dc motor with a magnet on the armature and a reed relay, anything to pulse the primary. Doesnt even matter what frequency. But remember you will have to experimented to get the best match for the longest lasting ability of the bulb, lowest current draw and brightest light output. Feel free to experiment. and report any good findings to help other people. I experimented on this circuit for 2 months. As well as a month with Peter. Trying to get the lowest current draw, easiest design, best light output, and longest battery life.
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