VHF Antenna too long
 

Stupid question but here goes. I want an antenna, 6-7 ft long...8 is too much. Lets not go into why. Question is..can I cut an 8 ft off and not ruin the antenna?

Re: VHF Antenna too long
 

VHF? Get a cell phone! :D

No, you cannot cut a 8' antenna, it's factory calibrated neither you should ever cut the wire. Look at Westmarine, they have many antennas of different lengths...

Re: VHF Antenna too long
 

Has to do with the wavelength that you will be transmitting/receiving on. JS232's advice is your best bet.

Re: VHF Antenna too long
 

Have you thought about a rachet mount and just tilting the antenna back so the vertical hieght is 6 or 7 ft?

Re: VHF Antenna too long
 

I broke my 8' mask off and the wire inside did not go all the way to the end of the mask ..... it was suspended by a piece of line inside the mask ...

Re: VHF Antenna too long
 

True what has been posted about cutting the antenna. Only should be done by a qualified tech with the proper equipment. The 8' length is the best for overall transmit performance given the VHF frequency you operate on. Unless you need some really long distance transmit numbers, there is an alternative. Look up www.antenex.com and their part number TRAT1500. A tunable 150-168mhz antenna. It does need a ground plane (metal plate) of a minimum of 20" overall diameter to perform properly. Once installed, tune using an SWR meter to get the LEAST reflected power on your most desirable channel you wish to transmit on. Good luck.

Re: VHF Antenna too long
 

ditch it and get a handheld. I'm sure you got a cell phone.

Re: VHF Antenna too long
 

Handheld is not much better than a cell phone offshore very limited range. VHF radio with at least a half wave length antenna is prudent.

Re: VHF Antenna too long
 

I disagree. Works 30 mi offshore for me..cell phone...

Why do you need a VHF when further than 5 mi out? Antennas is just another item to break. Only time I use VHF is for weather and calling marinas. I can't hear myself talk when running.

Call CG on cell and carry EPIRB if you are sinking.

Re: VHF Antenna too long
 

rotax...i dd look that up...never seen or used anything like that...we have worked w/atenex on few applications too.

"The gain of the an antenna is primarily determined by how many stacked elements, or radiators, it has. This results in longer antennas for higher gain levels. The addition of an extension does not affect the construction or electrical properties of the antenna, and therefore has no impact on gain. However, an extension does get your antenna higher off the water, which results in greater range."

call craig at race com! tell him what you need an what you want to do...if they don't have it, they will custom make it for you at a resonable price. he's a good guy with a TON of knowlegde and he will not charge you for advice. call 'em:800 990 9941

Re: VHF Antenna too long
 

Lets see.. mostly ditto Downtown.

JS... I am pretty sure that you CAN cut the coax as the resistance of a 75 ohm cable is in the dielectric distance. If memory serves... you can cut it down to like 6 feet. No shorter. Bad for amp in transmitter I think. When I replaced my eight footer on my last boat the instructions had a blurb about length. I had to re-terminate the cable to pass it through the hull so I went ahead and took some off rather than have a coil. Coil. Whole other show.

Anyway.... If we all promise not to criticize or make fun.... would the author of this thread PLEASE tell us why you need a 7 footer? I won't even smirk. I swear.

In fact... I will post something like... "Ohhh no wonder." or "That makes sense."

Re: VHF Antenna too long
 

Err, Um, Downtown42, you MUST have a working marine radio. Get an 8 foot antenna. The Coast Guard will not be happy if you do not have a hard mounted and working marine radio. Portable marine radios are great to have as BACKUPs or in your man overboard bag.

Re: VHF Antenna too long
 

Are you serious? I have proof of boarding last summer. Had to buy a bell and put a sticker for discharge or something like that.

Coasties were happy with me and very courteous.

Re: VHF Antenna too long
 

heres good info from an online boating course, not arguing each has their place.

Chapter IV - Legal RequirementsSection 3 - Recommended Equipment

Recommended Equipment

In addition to all the equipment that the U. S. Coast Guard requires, certain equipment and supplies just make common sense to have. The following are items that should be carried aboard:

VHF Radio
Anchor and ground tackle
Bilge Pump and or bailer
Boat hook
Charts and navigation publications
Compass
Detectors and alarms
Fenders
Lines
First aid kit
Flashlight and searchlight
Spare parts and tools
Windshield wipers
VHF Radio Communications


Although marine VHF radios are currently not a requirement for small recreational boats, this should be high on your list of equipment to carry. You should learn to properly use the radio and, during your passenger orientation, make sure at least one of your guests can also use the radio in case of emergency.

Distress Vs Non-Distress

Distress is defined as a situation where you or your boat are threatened by grave danger with lose of life or the vessel being imminent. Running out of fuel, a dead battery or other mechanical problems are not distress situations.

The Coast Guard serves as Search and Rescue (SAR) coordinator for all maritime emergencies and is the appropriate point of contact whenever you are concerned for your safety. If you are in distress the Coast Guard will take immediate steps to help you. Normally Coast Guard rescue boats and/or aircraft will be sent, but assistance from any available source will be arranged to expedite your rescue.

How To Signal For Help

First you need to be familiar with just a few of the many radio channels available to you. Channel 16 is the hailing and emergency channel. This means that this channel is used to hail (call) another boat, marina, the USCG, etc. You should not hold conversation on this channel. In non-emergencies use it only to contact another party and then switch to a "working channel" to carry on your conversation. There are many working channels to choose from. Just pick one, say Channel 68, and use it regularly. Another channel to remember is Channel 22A. This is the USCG's channel. Although you can contact them directly from Channel 16, you can also contact them on 22A.

If you are in distress use "MAYDAY, MAYDAY, MAYDAY" on the radio. If your situation is not a distress, simply call "Coast Guard." Channel 16 VHF/FM and 2182khz HF/SSB are dedicated distress and calling frequencies and are monitored at all times by the USCG.

Citizen's Band (CB) is not dependable and is not monitored at most Coast Guard stations. If you do not have a radio, attempt to signal a fellow boater who can assist or call the Coast Guard for you. In a distress situation, use flares or any other distress signaling device to catch the attention of another boater.

What To Tell The Coast Guard

While arranging help, the USCG will ask for the following:

Your location or position. (Make sure you know where you are at all times)
Exact nature of the problem (special problems).
Number of people on board.
Your boat name, registration and description.
Safety equipment on board.
When It's Not A Distress

The Coast Guard's primary search and rescue role is to assist boaters in distress. If you are not in distress and alternate sources of assistance are available, you should try to contact them directly. If you can not raise alternate assistance directly the USCG will normally coordinate the effort to assist you. If you have a friend, marina, or commercial firm such as a towing company that you want contacted, they will attempt to do so.

VHF Radio vs. Cellular Telephones

The Coast Guard does not advocate cellular phones as a substitute for the regular maritime radio distress and safety systems recognized by the Federal Communications Commission and the International Radio Regulations -- particularly VHF maritime radio. However, cellular phones can have a place on board as an added measure of safety.

There is no comparison between cellular phones and VHF marine radio. They provide different services. The cellular phone is best used for what it is, an onboard telephone -- a link with shore based telephones. A VHF marine radio is intended for communication with other ships or marine installations -- and a powerful ally in time of emergency. If you have a portable or handheld cellular telephone, by all means take it aboard. If you are boating off shore, a cellular phone is no substitute for a VHF radio. But, if you are within cellular range, it may provide an additional means of communication.

Re: VHF Antenna too long
 

Great Advice.

'cellular phone is best used for what it is, an onboard telephone -- a link with shore based telephones"

" A VHF marine radio is intended for communication with other ships or marine installations -- and a powerful ally in time of emergency."

Everybody has a cell phone.
Everybody should have a VHF.

I think Audacity's advice is on track.
Custom antenna must be tuned to the proper wave lenth.
The size is a divisible from the actual wave lenth.
They could custom make your lenth with a base load
at the bottom.


Gerry

Re: VHF Antenna too long
 

I had a 3 foot base-loaded metal whip on one of my previous boats. Transmitted and recieved well but raised hell with my depth finder every time I keyed it up.

Don't even know if those are still available but if they are, it's a pretty good alternative to an 8-footer.

BTW offthefront, it's a "mast" not a "mask". :p