![]() Portable setups though… an easy access rooftop is perfect.Īlso, if you watch the video you will see a tripod in the background. Permanently mounted transmitting antennas are not usually mounted in such places both to protect the antenna and to protect passers by. If this is a rooftop it’s a rooftop that is meant to be a regularly trafficked area. What I do see is there are bushes that appear to be on the same level and more telling. I can’t tell for sure if that is a rooftop or not. well lets just say I havent changed my setup(s) in about 7 years. Alot of room actually simple NiMH 9v(same size as alkaline) and a charging circuit, heck 2 ‘solar light’ cells work great at trickle charging a 9v, cause I use them to do my setups, since the 9v isnt used all the time, and very little ma are pulled to keep the circuit running and the trickle charging it more than the pull…. Or even here in AZ where the dust and dirt then freak rain storms like right now turns it all into mud, weather resistance at least to block some of all that to give it longer life so things dont short out… that would be helpful….usualy just a gasket(s) is all you need.īut if one lives in a good climate then even a gasket isnt needed.Īs for battery life, this i agree totally, and if one is so concerned with battery life from then from the looks of it, get a rechargeable 9v, put a/2 solar cells ontop of the box with a small charging circuit, cause the box has room for it that is for sure. I will tend to agree upto a point… depending on where you live weather proofing may be a concern, north west with the rains, and the weather or even snow problems etc. “weather-proofing and battery life is rarely a concern” If it was a permanent installation he would probably set it up differently – but bringing a two wire power line to power the tuner is still easier than long 4 wire setup driving the Ciger Also the stepper likely runs only few steps every once in a while and 99% of the time all the electronics is in low power mode, saving the battery. so weather-proofing and battery life is rarely a concern. Driving it using a phone/tablet saves him having to build a control box for it.Īlso these antennas are mostly meant as portable/temporary setups. All the switching and possible EMI mess is on short wires and in the null of the antenna, so will neither pick up RF nor cause you to “hear” it. The cheap BT module is actually a clever workaround for that. That’s really bad when you have to actually listen to the signal you are receiving while trying to tune this antenna (mag loops are commonly tuned “by ear”, to maximum noise/signal level of a weak signal – have one like that myself). I am not quite sure what you mean by “a lot of extra technology just because you can”?Ī long unshielded 4 conductor cable is a wonderful thing to get RF induced in and also the energetic switching pulses from driving the stepper would radiate from it like from an antenna, causing wideband EMI whenever tuning. ![]() Posted in Radio Hacks Tagged amateur radio, antenna, magnetic loop, magnetic loop antenna, radio Post navigation We’ve only brought you one magnetic loop antenna in the past, whose special feature was that it is portable. He’s posted a video of the unit in operation which we’ve posted below the break, if you’ve ever had to constantly retune a magnetic loop you will appreciate the convenience. We’d be interested to know what the effect of a high RF field is on these components, but he doesn’t report any problems so it must be working. The stepper is connected to the capacitor via a short flexible coupling, and tuning is performed with the help of a custom Android app. His solution is an elegant one, he’s made a remote retuning setup using a stepper motor, an Arduino, and a Bluetooth module (translated here). has a magnetic loop, and soon tired of the constant retuning. Magnetic loops have the advantage of extreme selectivity and good directionality, but the danger of a high voltage induced across that tuning capacitor and the annoyance of needing to retune every time there is a frequency change. It’s different from most conventional wire antennas, taking the form of a tuned circuit with a very large single-turn coil and a tuning capacitor. If you are a radio amateur, you may be familiar with the magnetic loop antenna.
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