FAQ - Fiber antennas
Question: Is a Ground Plane required for our antennas?
No. As a result of our design and the "Tuning" that we perform at our factory, no ground plane is required.
Question: What makes your antenna different from your competitors?
Answer:- All of our antennas are hand assembled and tuned for maximum gain.
- All of our connections are soldered, whereas our competitors use mechanical joints (crimping), which is less reliable and often fails under salt water conditions.
- Digital Antenna uses its exclusive marine grade low loss UV stable RG-8X cable to reduce transmission line loss in all Digital Antenna marine antennas.
- All of our antenna bases are epoxy glued and filled with silicone base caulking to insure complete watertight seal. Our competitors use rubber gaskets and do not fill the ends. Often, the rubber gaskets fail with time.
- Bottom Line: Our antennas are better made, more reliable and outperform all other antennas on a category by category basis.
Question: What should be the main reason to buy your antenna?
Answer: The antenna is part of your life support system during an emergency. Reliability should be the main decision factor in purchasing our antenna. The radio and antenna act as one system that must perform in all weather conditions and at maximum range. Simply put, having a good radio with a poor antenna does not give you the best odds when you are in a distress situation. It is our belief that Digital Antenna has the best and most reliable product on the market -- one that beats the competition in both gain and distance, resulting in an increased safety margin.
Question: Is it true that the higher the antenna, the further the transmission and the better the reception?
Answer: Yes, in general, that can be one of the factors influencing performance. However, for most uses, mounting the antenna in the usual locations is acceptable.
Question: Does the gain of the antenna really matter?
Answer: Yes, it does. The gain of an antenna translates to greater distance for transmission and reception. A gain of 6db usually results in a performance increase of four times the radio's power output and eight times with a 9dB gain. However, other factors can be equally important, including the tuned frequency of the antenna and its SWR. Digital Antenna tunes all of its products in accordance with the median frequency of usage, (i.e., VHF will be tuned for 156.8 Mhz). Our SWR ratio approaches 1:1, reducing most of the losses associated with our competitors' antennas. All of these factors are important when it comes to choosing an antenna.
Question: I have a Shakespeare antenna and I am unhappy with its performance. Can I use your antenna as a replacement without having to buy a new mount?
Answer: Most of our antennas fit into the standard mounts of our competitors. For best results, prior to ordering, please go to our technical support page and email us with the make and model number that you want to replace. Then, we can be sure that the replacement will fit your mount.
Question: Why should I purchase your cellular antenna? Isn't the one I have on the phone good enough?
Answer: Our cellular antennas are tuned for maximum gain and distance. One customer reported that his cell phone reached Miami, Florida's towers from Bimini, Bahamas, more than 45 miles across the Gulf Stream. The little antenna on your cell phone simply does not have the gain or range.
Question: What is the minimum distance that I can mount the antenna from the radio?
Answer: In order for no squealing to occur from transmission interference, you must mount the antenna no less than three feet away. Of course, the greater the power of the radio, the greater the minimum distance.
Question: How do power losses occur in an antenna?
Answer: The gain of an antenna is closely related to its directivity. Because directivity is based solely on the shape of the radiation pattern lobes, it does not take into account power losses that may occur in the actual antenna system. Every Digital Antenna marine antenna is tuned for minimum standing wave ratio (SWR) which approaches 1:1, reducing the system loss significantly. Additionally, a ferrite choke bead is used to contain RF power in the antenna system. By using a choke bead, all RF power is directed into the radiating element and prevented from leaking back to the transmission cable. This technique increases usable RF power and minimizes cable interference with other electronic equipment. Also, Digital Antenna uses its exclusive marine grade low loss UV stable RG-8X cable to reduce transmission line loss in all Digital Antenna marine antennas.
Question: What is gain in an antenna?
Answer: Gain in an antenna is not the creation of power, but rather a simple refocusing of energy from all directions to a specific direction. Gain is measured in decibels (dB). Vertical antennas are in fact quite directional, except in the horizontal or azimuth plane. The figure to the left shows the radiation pattern of three different length radiating antenna elements. Note that the quarter wavelength antenna has the highest angle of radiation; however, it also has the lowest gain of the three cases. The 5/8 wavelength antenna has both the lowest angle of radiation and the highest gain, which gives superior performance at sea level.
Question: How does the ground system affect an antenna?
Answer: The vertical antenna works well only when placed over a good ground system. The success or failure of an antenna system depends on whether or not it has a good RF ground. Poor grounds cause antennas to operate at less than best efficiency. In fact, it is possible to lose between 50 and 90 percent of the RF power by heating the space under the radiation lobe, instead of transmitting into the air.
Question: What makes an antenna reach a greater distance?
Answer: The advanced ground system internal to all Digital Antenna marine antennas allows 4.5dB through 10dB gain antennas to have a greater range in any sea conditions. The figure below shows the effect that a ground system has on a vertical antenna. Note that by increasing the ground system efficiency, useful RF power is actually directed closer to the water surface where it is needed. Most well designed 5/8 wavelength 6dB antennas will transmit the same distance in the sky; however, the ground efficiency determines the actual communication range at sea level.
Question: Can I use your antenna for land based applications?
Answer:Yes. Our antennas are superior to the land-based antennas sold by our competitors. Just check your mounting needs.
Question: I am in a fringe area where reception by my cellular phone is erratic. Will your antenna help me?
Answer: Yes, it will. As long as you are getting some signal, the antenna will increase the reception and transmission of your cellular phone.
Question: I have a Nextel Phone. Can I use The Booster?
Answer: There is a special booster for the Nextel system. BST801
Question: Can I use The Booster in my automobile?