where to mount VHF antenna

[Sea-Dog]

Howdy,

I am trying to decide where is the best spot to mount my 2.4M VHF antenna on folding base.

I have 3 spots in mind.

I think that wherever I mount it - it's going to get in the way sometimes.

The boat has a raised casting deck in the bow. If I mount the antenna at the rear of the casting deck on the starboard side - it may get in the way of throwing the cast net.

The same if I mount it just off to the side of the bow.

If I mount it on the port side at the stern, it would likely get in the way of rods when fishing off the back of the boat. I suppose it would be easy enough to pass the rod around the antenna wherever it is.

Another option I am considering is to buy a short VHF whip antenna, (about 600mm long) and mounting that up near the bow.

At least the whip antenna would be easier to fish around - just lift the rod over the top of the antenna. I'd just have to remove the antenna when cast netting.

Can you use a spring base with VHF whip antennas like I used on the CB antenna on the roof of the car when I was a lad? - that could make things a bit easier.

In the pic below are my 3 choices of location. The starboard side mounting would be mounted on the inside of the gunwale to protect the antenna from being smashed by my kids getting into the boat when the antenna is not raised.


Opinions please............

[FNQCairns]

Sometimes nowhere on the boat is good as you say, I would vote for up the front with the shorty but include the longer one in the boat for any time needed, the chance that it will never ever get fitted for a real reason is a strong possibility.

I run the shorter one myself on top of my CC and it does a fine job 40km offshore, still physics says the longer one must be better again, for around MB and poking a little further a field the shorty will be fine IMO.
cheers fnq

[ozbee]

right next to the driver seat it will lay down on the gunnell for protection ,its to far back for casting problemns and also when fishing out the back there no law saying it has to be upright as i assume i wouldn't find you 100ks out to sea.

[Spaniard_King]

Pacific make a removable antenna (the base remains and you simply screw the top on) possibly a better option than simply a fold down one

My choice is for the bow option as if required you can fold it down allong the side following the curve of the boat (it will bend nicely along the curve) holding it in position with a flexible cord or uncrew and remove to a side pocket as I sugested above.

[finga]

My vote is for the bow as well.
With my tiny tiny tinny I made a mounting bracket up so when the aerial is folded down it's below the level of the gunnel. It's very well protected there.
When your fishing or chucking the cast net just fold it down.
It's one of those Pacifics like Gary has mentioned and when I'm fishing the creeks I just take it out and leave it in the shed.
I mainly have the radio for when I'm down the Pin or in the Bay.

I wouldn't do the whippy, stumpy thing.
The radio may not have the legs to transmit when you really need it.

[TOPAZ]

Hi all,

Don't forget that radio waves travel in straight lines, and therefore the HIGHER you can mount the antenna, and the LONGER the antenna, the better your radio transmission/reception will be. (It's due to the curvature of the earth)
So a short antenna on the bow is not a good option.


Richard.

[Ally Jack]

Sea Dog,
I've been thru the same drama's with my last boat. I mounted mine on the starboard gunnel (see attached pic)mainly cause the bow mount covered the other. It was a bit of a pain being there early on but I got used to it and worked around it.
I caught the bow mount with the cast net more times than I ever caught the aeriel mount.

Ally Jack

[White Pointer]

G'day,

The best shot is to position the radio close to the antenna. This reduces cable runs which are a source of problems with radios.

Keep the antenna base in a position as much protected from salt as possible. Salt wrecks antennea and their base mounts. Thorough cleaning can prevent premature corrosion.

Have as tall an antenna as possible especially if you are going outside.

Talk to your local VMR about this. They are a wealth of information on what works and what doesn't.

White Pointer

[Sea-Dog]

Thanks for all the replies.

I might try the short whip antenna in the bow to see how the reception is.

I don't plan to be going outside the confines of the bay, so long range is not going to be a problem.

In fact the shorter antenna may improve things. I remember reading somwhere that the longer your antenna - the flatter the radiation pattern will be.

Conversely, a short antenna will have a much rounder radiation pattern.

I have had the same antenna on another boat and couldn't be heard by the local VMR until I was well away from the tower. My signal was slipping beneath their "ears"

So the short antenna will send more RF upwards as well as outwards.

That way, I can log in from the ramp, not the middle of the bay.

I will keep the longer antenna until I've seen how the shortie whip goes for reception and transmission strength. If the shortie is no good, then the long antenna will be the one that gets mounted and I'll just lower it when casting.

Cheers, Ross

[oldboot]

I would not be speculating that a shorter antenna radiates better.....at VHF it is most unlikley.

As for shortening cable runs......most of the ground independent aerials are fitted with a specific length of coax that should not be shortened...... so unles you boat is long and you have the radio at one end and the antenna at the other it wont be an issue.

remember it is quite reasonable to lower the antenna if you need to.

Personlay I'd be going for the 2.4m antenna( that was the advice I took from an ex GME Tec' friend of mine) and tucking it under or along the gunwal when stowed.

remember if you are going out week day you want to be able to crack seaway tower or bribie.

cheers

[walruss]

Garry,

Re the removable antennae from Pacific. Do you more details what the model is etc.
Having removable antennae sounds good, as I have had one with 27MHZ but didn't know one was available for VHF, as I hadn't found one.

Thanks

Russ

Ps probably should have added for a fibreglass boat

[Sea-Dog]

Garry,

Re the removable antennae from Pacific. Do you more details what the model is etc.
Having removable antennae sounds good, as I have had one with 27MHZ but didn't know one was available for VHF, as I hadn't found one.

Thanks

Russ

Ps probably should have added for a fibreglass boat

I think both Bias and BCF have the Pacific antennas, possibly Whitworths too.
They say on the packaging what band they are for. IE 27Mhz or VHF

************************************************** **

By the way, I went looking for one of the short whip antennas today and they only come with about 3M of coax cable. Too short a run for where I intended it.
So I have just mounted the 2.4M on the inside of the gunwale on starboard side, just about level with the back end of the casting deck.

I also bought a little nylon clip that is screwed to the inside of the gunwale about a foot from the end of the antenna. The antenna clips into it to stop it from flopping around when the antenna is folded down.

Something else I bought for the boat was a source of shade until I can justify buying a bimini. I bought an aluminium framed market umbrella from Bunnings.

I know I can't travel with it up, but it will keep the kids out of the sun quite effectively. 3M in diameter provides quite a lot of shade for the boat.

My tinnie is 4.85M long with a flat floor and pedestal seats that fit into sockets in the floor. I can put the umbrella into whichever of the seat sockets as appropriate, then just crank the handle to wind her open.

I can even use it at home for the outdoor table.

It was display stock at Bunnings and they didn't have any in cartons, so I bagged it for $30 as it was quite dusty - big deal.

Just love a bargain

[Spaniard_King]

Any One who stocks BLA Products will Have them

have a look here http://www.bla.com.au/index.php?dId=...1fa7f631ae8b46