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아래는 Radiointel의 리뷰입니다
One of the most useful and fun toys in my antenna arsenal is the C.Crane Twin Coil Ferrite antenna. This $99.95 antenna can dramatically improve your AM reception with virtually any radio. I have used it with many radios from portables to large table tops and it has worked equally well with almost all of them. The "Twin Coil" can bring virtually any decent radio to life making it far more sensitive and selective then you ever imagined it could be. More good news…it doesn't matter whether the radio has external connectors or not. It can also make many radios far more convenient to use because of its immense adjustability and flexibility as you will see.
WHAT IS IT? SETUP & METHOD OF CONNECTION If your home or office blocks AM signals, such as mobile homes or brick and steel buildings you can place the receiving element on a windowsill for greatly enhanced reception. It can even be remotely mounted up to 75 feet away with the accessory extender cables, and can be mounted outdoors if needed. The only problem with remote mounting is that the antenna is highly directional. So unless all your desired signals will be coming from the same general direction you may want to find a way to rig a rotor to it…this will require some ingenuity as the antenna is not prepared with a standard mounting option. It can certainly be done and many owners are happily using their Twin Coil antennas with rotors to great advantage. And even without a rotor you will still get greatly improved reception and you may find one position that works perfectly for you. Experimentation is the key here. An external ground connector is available for outdoor installations.
WHEN TO USE THE FERRITE SENDER WHEN TO USE THE DIRECT CONNECTION First, know your radio. If your radio has an antenna jack, first determine if using that jack disconnects the radio's built in AM antenna. Some do, some don't. If the owner's manual isn't clear on this (as is often the case) the way to tell for sure is to put a plug into that jack and see if your AM reception disappears or stays the same. Obviously, if it disappears, you know the internal antenna has been disabled…that is desirable. If reception stays the same, you will be getting signal from both the internal antenna and the Twin Coil when you use that jack. While this is generally not the best arrangement because it reduces your ability to null interference with the Twin Coil antenna element, in practice it often doesn't matter very much. You may receive some interference from the built in antenna, but usually the signal from the Twin Coil is so much stronger that the signal from the internal antenna is overwhelmed by the stronger signal from the Twin Coil and therefore ceases to be much of a problem. Also, if you find that the direct connection yields lower signal strength than using the Ferrite Stick sender unit that means your radio has AM attenuation on the input jack and you should use the sender instead. If your radio has antenna screws or spring clips for bare wires, your internal antenna will still be active as well…those screws and clips merely connect to a few turns of wire wound around the internal rod antenna. Try the direct connection versus the sender to see which works best for your radio. Finally, many new users first try the antenna at night and report that it does nothing. That is because they don't understand that at nighttime signals tends to be much stronger. To compensate, the radio's built in AGC (Automatic Gain Control) works to reduce their strength to prevent overload. Adding the Twin Coil Antenna still increases the signal strength even more, but the radio's AGC just turns the gain down further to compensate, so you may not notice the effect. This also makes it much more difficult to find the sweet spot for the sender, which is why I recommended initially using a weak daytime signal. This doesn't mean that the Twin Coil does nothing at night. It can still improve reception dramatically by reducing fading and interference and by giving you more directional control. Some night signals are dramatically cleaned up using this antenna, even though initial observations may reveal less of a difference. USING THE TWIN COIL/HOW WELL DOES IT WORK? One of the big benefits of the Twin Coil antenna is that it can be positioned and rotated independently from the radio. This is a real necessity with big tabletop radios such as Trans-Oceanics and Grundig Satellit's. The radio can stay put while you rotate the antenna for best reception. Its ability to null out noise sources is sometimes phenomenal. Here's one example. One of my favorite tube-type receivers is a Zenith Trans-Oceanic A600L. Unfortunately it picks up lots of interference from my computer in my home office, rendering out of town AM signals unlistenable. With the Twin Coil I found a great spot for the Antenna Element which was only a few feet from the radio, but in that spot the interference virtually disappears, leaving only a strong signal. The difference is astounding and I can actually listen to stations that were completely unlistenable before. Most of my radios show substantial improvement not only in signal level but in quality of reception. The Twin Coil is MUCH more sensitive than my passive loop antennas and much more convenient because with those loops you have to rotate the radio along with the loop for best performance and sometimes that is not convenient. I do own two radios which don't improve noticeably with the Twin Coil, a GE SR II and a Panasonic RF-2200. (Note that it DOES improve my GE SR III). It would appear that these radios's extreme sensitivity is the reason, but I am only guessing. With every other AM radio I've tried from my Sony 2010 and Eton E-1 to big and small table radios and shortwave radios, both desktop and portable, the C.Crane Twin Coil Antenna will transform your listening experience. I own two of them and I can't recommend it highly enough. At under $100 it will usually do more for your AM reception than buying a new radio. Download product Info and owner's manuals at: http://ccrane.com/ Comments or questions? Email me at jay@radiointel.com | ||
첫댓글 참고가 됩니다만, 과연 설명대로 AM 주파수에서 안테나의 위력이 돋보일까요?저도 SONY AN12 안테나를 구입해 사용해 봤으나 웬 잡음이 그렇게도 많이 들어오는지 요즘은 사용을 않고 있습니다. 공간만 허락되면 롱와이어 안테나가 값싸고 이용하기에 무난하였습니다.
오랜만이네요 중파안테나는 신호를 아무리 증폭해도 잡음과 같이 증폭되기에 잡음을 제거시키는 능력이 더 중요한 요소로 작용합니다 루프안테나 형태가 아니면 가격대 성능비를 만족하기 어려울듯 것 같습니다 참고하세요