General Questions

Do you sell direct to consumers?

No, we sell through our dealer channel, please use our dealer locator to find your local dealer.

What are the differences among the many styles of antennas?

The antennas differ in type and size of their elements, ferrule material, the way the antennas’ fiberglass is wrapped, and the coax cable that is used. These factors determine the basic cost of building the antennas. To this, add the relative cost of the finish that is applied.

What is antenna gain, and how is it measured?

Gain is an increase in effective radiated power (ERP) from an antenna, usually stated in dB (deciBels). As a rule of thumb, you can multiply the radio’s output power by 4 for 6dB antennas and by 8 for 9dB antennas. A 3dB antenna gain gives an ERP of 2 times the radio’s output power. A Unity Gain antenna provides no increase in ERP.

Can I use two radios with one antenna?

Yes, Shakespeare offers a product that makes this possible with our AS-2 switches, which allow for hook-ups of this nature. The AS-2 is an automatic switch for two radios connecting to one antenna. It electronically senses which transceiver is used and switches the antenna. Further instructions are on the packages.

Is it better to use a dedicated AM/FM antenna or a band separator?

Shakespeare recommends using a separate antenna for this purpose, if possible. Band separators were designed for boats that don’t have room for two antennas. Be sure the antennas are mounted at least three feet apart.

Can I paint the antenna, and with what?

Yes. Shakespeare’s antennas can be painted any color you wish. Be sure not to use any paint containing metallic chips or lead bases. To prepare the surface, wash the antenna with soap and water and allow it to dry completely. Paint the antenna with polyurethane or a lead free, non-metallic paint.

Can I repair the antenna if the fiberglass becomes frayed?

Yes. Wash the antenna with soap and water first and allow it to dry completely. Next, paint the antenna with polyurethane or a lead free, non-metallic paint. Then lightly sand the surface with 400-grit sandpaper. Additional coats of paint may be added but are usually not necessary.

What antenna should I use with what radio?

It depends on your needs and the amount of space that is available to mount the antenna/radio. Some considerations are: the height at which you can mount the antenna; whether you have to raise and lower it to fit under bridges, boathouses or other obstructions; and how far you need the transmitted signal to reach. The longer the antenna, the better coverage you can expect, generally speaking, if a larger antenna will fit on your boat. Always purchase the best antenna you can afford, since the antenna is the most important part of any VHF installation.

VHF Antennas

How can I check the VHF antenna to make sure it is working?

There are a few options, the easiest is to do a radio check on a commonly used channel for your area (note that the U.S. Coast Guard frowns on radio test calls made to them, Channel 16). Another option is to call a friend on a channel you agree upon from a range of known distances, then have the friend assess your transmission for quality. The final fail-safe option is to measure the efficiency of your antenna/radio system more scientifically. Shakespeare makes an antenna / radio tester – the ART-3 Tester. The ART-3 measures transceiver output power, antenna VSWR, and proper receiver sensitivity.

How do you install the PL-259 connector?

An instruction sheet for installing the PL-259 connector is included with the antenna. Follow the instructions and consult the diagrams. For true ease of installation without soldering, check out Shakespeare’s innovative Centerpin® solderless connectors. The PL-259-CP-G and PL-258-CP-G connectors are gold-plated brass construction. If all else fails, there are a few videos on YouTube that walk you through the process, just google “How do you install the PL-259 connector?” and there are many video options to choose from.

Can I cut the cable on my VHF antenna?

Yes, if you need to. However, you should leave at least three feet of coax cable, measured from where the cable exits the antenna. Note: This is NOT true for all antennas. CB antennas’ coax generally should NOT be cut. See separate question regarding CB antennas’ cable length. Reasonable lengths of excess cable can be rolled in a coil of at least 8 inch diameter and stowed in an out-of-the-way place.

What is the transmission line loss for coax?

This depends on the amount, as well as the type of coax used. On the average, 50 feet of RG-58 coax will have about 3dB loss, 50 feet of RG-8X coax will have about 2dB loss, and 50 feet of RG-213 (RG-8U) will have about 1dB loss.

Will metal or other objects that are close to the antenna affect it?

Yes. It is best to locate the antenna at least three feet from any metal objects or other antennas.

Will my antenna work on an aluminum boat?

Yes, that’s why our antennas are internally grounded.

Can I mount the antenna beside the radio?

No, it must be at least three feet away from the radio, so transmission will not interfere with the radio’s reception. When mounted too close to the radio usually there is a “squeal” that can be heard from the speaker.

How high must the antenna be?

There is no particular height requirement. However, the higher the antenna, the better the antenna’s range and performance.

What range can I expect from the antenna?

To determine the range of an antenna, multiply the square root of its height (In feet) above water by 1.42. This gives the range in miles. Remember to perform the calculation for BOTH vessels, then add the results to get the range between two vessels.

Do I need a ground plane for a VHF antenna?

Not necessarily. Shakespeare VHF and CB Marine Band antennas are designed with independent ground planes built in. SSB antennas, on the other hand, must be properly grounded.

What is the antenna’s wavelength?

It can range from 1/4 wave to 5/8 wave, depending on the length and style of antenna. Please see the antennas’ specifications section for information on your particular antenna.

Can I use my VHF antenna for AIS?

Yes and No, you can use a VHF antenna for AIS receive. To transmit AIS you will need a dedicated AIS antenna. If not possible to have a dedicated AIS antenna, and you only have one antenna on the boat, make sure it’s a VHF antenna because that’s the primary form of communication. Please note you will need a splitter to accomplish this (sold separately). If you have independent VHF and AIS antennas on a sailboat, the VHF antenna should be installed at the top of the mast, the AIS should be installed lower down on a radar arch. Due to the fact that range is not as important to AIS.

What is the receiving zone for my antenna?

On all Shakespeare VHF Marine antennas, the receiving zone is 360 degrees – or omni-directional.

How much power can I put into the antenna?

Maximum power input varies with the model and type of antenna. Please see the antenna specifications pages.

Phase III Series Antennas

What is the warranty on Phase III antennas?

8 years

Do all the antennas have silver-plated elements?


Why is silver plating the antenna element a benefit?

There are two main reasons to silver plate an antenna element. First, silver is a much better conductor than brass or copper alone. Second, over time, as the silver surface oxidizes it becomes silver oxide, which is a better conductor than the oxides that form on un-plated brass and copper.

How can I mount my new Phase III antenna?

All Phase III antennas have a standard 1in-14 thread bases that will work with standard marine mounts. The antennas have the added bonus of being mast mount ready with appropriate U-bolts or strapping.

What coax should I use with my new Phase III antenna?

Any 50-ohm coax may be used with the antenna (except AM/FM) as long as it is sized appropriately for the cable run needed.

How do I clean my new Phase III antenna?

A mild detergent or soap and water may be used to clean the antenna. The use of abrasives or cleaners that contain any solvents should be avoided.

Do I need to tune my antenna?

No, this is not necessary as these antennas are pre-tuned at our factory for maximum performance and efficiency.

TV Antennas

How long is the warranty for the TV antennas?

SeaWatch® Marine TV Antennas carry a Shakespeare Limited Warranty for 2 Year from the date of purchase.

How can I check the SeaWatch® Marine TV antenna to make sure it is working?

Check the voltage from the power supply for 110V AC operation and 12 vDC on DC operation with a voltmeter. If you are experiencing difficulties, try moving out of the slip to see if interference from other boats might be causing your reception problem. VHF TV transmission is line-of-sight, so at sea level you’re quite possibly out of “view” of the TV signal.

Why can I pick up some channels but not others?

Marine TV antennas have the same limitations as the ones that install on top of your home. Poor reception can be caused by location, height (for example, is your boat at sea level?), atmospheric conditions, and power. Make sure your antenna has an open and unobstructed view of the sky.

Can I mount the antenna upside down or sideways?

Yes. However, be sure to seal the coax connector located on the underside of the antenna. Please note this will also diminish the performance of the antenna.

Can I mount the antenna in an enclosed area?

No. TV signals bounce off flat, reflective surfaces, which would effectively shield the antenna from the station’s broadcast.

Can I run two or more TV’s off of the same antenna?

Yes, two TV’s will work with one antenna, as long as the total coax run is kept relatively short. Our Antennas are set up to run a max of 2 TVs.

Cellular Antennas

How can I check the cellular antenna to make sure it is good?

Unfortunately, there is no sure test. The best suggestion is: if the signal strength meter on the phone is low or shows no signal, there could be a problem.

Will other objects close to the antenna affect its performance?

Yes, they will. It is best to locate the antenna at least three feet away from any metal objects or other antennas.

How many feet of coax can I use with the cellular antenna?

The only limit is practicality. However, remember that at the frequencies of Cellular communication, great line loss will be encountered with long coax runs. For best performance, keep the coax short and be sure it is the best grade possible. LMR-400 low-loss coax cable is specifically designed for cellular antenna installations.

Where can I get technical assistance?

For technical assistance with the Shakespeare Stream or Super Halo products, please call or email SureCall at 888.365.6283 or support@surecall.com.

Satellite Antennas

Troubleshooting steps for Sirius Satellite Radio Antennas (SRA-50).

If you are not getting any signal, the first step is to contact Sirius and make sure they can see your antenna on the network. 855.796.9847 or marine.support@siriusxm.com

Can I mount upside down?


Can I cut the cable?


How high must the antenna be?

Satellite Radio antennas only need a clear view of the Southern sky – for them, height is not as important as the unobstructed view to the satellites.

CB Antennas

Can I cut the cable on my CB antenna?

Shakespeare CB antennas are specially built to allow trimming the coax: the Galaxy® Style 5223-XT Note that this answer applies to CB Marine Band antennas – VHF antenna coax is not part of a tuned system and can be trimmed. Reasonable lengths of excess cable can be rolled in a coil of at least 8-inch diameter and stowed in an out-of-the-way place.

Why does my antenna system have a high SWR?

There can be quite a number of reasons for this. The most usual reasons are coax having been cut or altered, coax running through conduit, antennas located near metal objects, or people standing too close to the antenna while SWR readings are being taken or improper installation of the PL-259 connector.

Do I need a ground plane for my CB Marine Band antenna?

No, all Shakespeare CB Marine Band antennas have independent ground planes built into them.

Mounts and Accessories

What threads are used on the Shakespeare mounts?

Most of our threads use a standard 1’-14 threaded mount.

What’s the difference between the 4187 and 4187-HD?

The 4187-HD is a similar style and design as the 4187 with extra strength and rigidity. Use wherever its extra heavy-duty construction is needed, for example with longer and or heavier antennas.