Betso has made itself known for creating excellent, highly accurate timecode products for location use (you can see my review of the Betso SBOX-1N here), but it is my opinion that their latest product entry, the Betso SHARKIE LPDA active antenna, will establish Betso as a force to be reckoned with in the wireless arena as well.
The Betso SHARKIE is an active, log-periodic dipole array (LPDA for short, also commonly referred to as a shark fin) antenna, with an operating frequency range of 470 – 850 MHz, and a directional cardioid pattern (perpendicular to the radial elements) yielding about 8dBi of passive forward gain – meaning that it is almost three times as sensitive to RF energy radiating on axis to the front of the antenna than it is off axis to its rear, as well as in comparison to that of an omnidirectional isotropic source.
Beautiful Design, Built for Location
Betso did their homework. Not only did they make a beautiful product with the Betso SHARKIE, but this antenna was also built with the challenges and difficulties of location use in mind. The superior build quality of this product is instantly noticeable upon sight, and that notion is only further reinforced upon inspection. First, the compact, perforated, glass-reinforced epoxy laminate antenna structure makes for an extremely light design, boasting an impressive small weight of around 320 grams (or 0.7 lb.). While the antenna is light, durability never comes into question. The structure is rock solid, inspiring a lot of confidence. The perforated design also helps greatly with reducing wind resistance, which we all know is essential when working under less than ideal exterior locations or follow car set-ups. Second, the amplifier (which we will cover next) is made of a CNC milled aluminum alloy, again, further inspiring confidence that this product will withstand any rigorous situations. Additionally, the amplifier electronics are all sealed, creating an antenna that is extremely weather resistant. The Betso SHARKIE will meet any physical demands from location work.
Goldilocks Amplification, Easy Operation.
Active antennas are all about getting that Goldilocks range of RF energy into the receiver’s input. Too much cable and insertion loss will create a weak RF signal by the time it arrives to the receiver, effectively reducing your operating range. Too much RF energy can overload the receiver’s front end, also reducing your operating range. And while other active antennas only offer 3 or 4 broad gain settings, the Betso SHARKIE provides an ultra low-noise amplifier with -9 to +18dB of gain in 1dB steps. The amplifier IC chip produces less than 0.75dB of noise, ensuring little to no degradation in the signal-to-noise ratio (SNR) of your RF signal. These are not the only parameters that matter, though. A low voltage standing wave ratio (VSWR) value of less than 1.2:1 guarantees excellent transmission-line efficiency and less reflected energy. Finally, a very high third-order intercept point (IP3) value of more than 34dBm makes sure that there is greater linearity and selectivity against closely spaced RF signals.
Thanks to its impressive specs, using this antenna becomes a very simple endeavor, and yet provides amazing results. Simply plug in a coaxial connection from a receiver or multi-coupler that is able to provide a DC bias between 5 – 20VDC (or use a Lectrosonics Bias T for those devices that are unable to provide DC bias), and voilà, the antenna automatically powers on and is ready for operation. It even remembers its last gain setting.
The Betso SHARKIE has very low power consumption, around 35mA (depending on display mode settings). The display brightness can be adjusted automatically thanks to its built-in light sensor, or it can be adjusted manually or even turned off altogether (stand-by mode) to help reduce power consumption. If turned off, simply press any button to turn the display back on for 3 seconds to allow display of current gain or to make gain changes. Longer cable runs with higher cable attenuation and signal loss can be easily made up by dialing in a higher gain value. Shorter cable runs and/or strong RF signals (including undesirable signals from high powered TV transmitters) that could overload the receiver’s front end can be easily attenuated by dialing in a lower, zero, or even negative gain value. The wide gain range allows maximum flexibility for a variety of set-ups and cable runs, while the ability to adjust the gain value in 1dB steps allows maximum control to ensure that goldilocks effect.
The Amateur Radio Repeater Geezers United Society (ARRG) has a nifty cable loss calculator you can use to help figure out how much gain needs to be made up depending on the cable run length, the type of coax cable, among other factors. Remember to also account for any insertion loss caused from splitters or extra connections in your calculations!
Built-in Filters Equals Less RF Garbage
The Betso SHARKIE also has a built-in high-pass filter with a roll-off frequency of 470MHz and a low-pass filter with a roll-off frequency of 850MHz, both with a relatively gentle slope. This results on the successful attenuation and elimination of unwanted RF signals that lie outside the operating bandwidth of the antenna. This includes walkie talkies, radio stations, remote controls, wireless focus systems, GSM, 3G, LTE, WiFi devices, bluetooth devices, mobile phones, etc.
Putting the Betso SHARKIE to the Test
The specs do not lie. This antenna is made to be easily deployed to any workflow. Using the Lectrosonics Bias T, I was able to integrate the Betso SHARKIEs to my bag cart set-up, and along with a mast and some decent RG58C/U 50 ohm coax cable I was able to remote the antennas up about 15 feet to achieve better line of sight to the body pack transmitter on my walking subject. I only required to make up 3dBs of gain on the antenna to achieve optimal operating range. Transmitter output power was set to 50mW. At Forest Park in Queens (in an relatively open field with very little to no reflective surfaces), I was able to easily achieve over twice as much range from the SHARKIEs connected directly to my receiver as I did from quarter-wave whips on my second receiver tuned to the same transmitter. I refrain from giving exact distance figures, as the operating range varies greatly from place to place, and there are so many unmeasurable factors that can come into play. So remember, your mileage may vary greatly.
As an added benefit, you can easily remote these antennas further if need be. Move the antenna and extend your cable run as needed to get to the ideal distance and line of sight to transmitters, and a simple press of the up arrow to increase the antenna gain will make up the additional loss. Please note, these antennas cannot be used without DC bias (no active antennas can). I mean, they do work without DC bias, but the signal is attenuated about 20dB, and a simple test demonstrated that the operating range was almost unusable (about two-thirds to that of whips).
What’s it Worth?
It’s not cheap. But I learned a long time ago that you get what you pay for. Each antenna costs EUR €479. After currency conversion, that comes to about USD $521 at the time of this writing. Most dealers on this side of the Atlantic ocean are currently advertising a USD $579 MSRP, however, I would check in with your favorite dealer to make sure that is the actual current pricing. You’ll need two for your diversity system. All in all, not that expensive when compared to other active LPDA antennas that don’t offer nearly as many great features and specs.
Protecting Your Investment
Don’t forget to get a Betso SHARKIE nylon pouch along with your SHARKIEs. This pouch will carry up to two SHARKIEs, each separated by an internal soft divider. It will protect your antenna investment from rain, dust or scratches while in storage or transportation. A must, and quite affordable at around USD $30 (actual retail price is EUR €25).
Product Review Summary
- Rock-solid build quality, yet light and compact!
- Perforated design; less wind resistance and lighter.
- Cardioid directional pattern; 8dB of forward gain.
- Ultra low-noise amplifier (< 0.75dB).
- Wide amplifier gain range from -9 to +18dB, in 1dB steps.
- Bright blue LED display with automatic / manual brightness and stand-by mode.
- Plug and play; automatically remembers last gain setting!
- Low power consumption; around 35mA!
The Not So Good
I’m not going to lie, I’m very impressed: I’m giving the Betso SHARKIE 4 and 1/2 stars. Honestly, the only thing that is keeping me from giving it a perfect 5 star rating is the cost. As I said before, you get what you pay for, and when it comes to wireless systems that really holds true. The cost of two SHARKIE antennas for a multi-channel diversity system pales in comparison to the cost of a multi-channel diversity system itself, but the cost of the antenna may indeed hold a few buyers back since there are other options that are less expensive that perform very well in comparison.
However, for the professional sound mixer, look no further! This is in my opinion the best shark fin antenna for location use. Top-notch build quality and components, light, compact, easy to use. Need I say more? No, I already did! See above!
You can find the Betso SHARKIE manual here.
Please feel free to leave any questions, reviews or opinions in the comments!