one for Jon Brooks. /vhf

[eupa]

Two weeks ago, I had to use the VHF to talk to control at Nieuwport. What surprised me was that the comms was very poor., i,e needed a lot of squelch to get a decent understandable message... It made me wonder -- where are the digital radios?? would they be better??. - is the range better?- obviousely there would be many more channels that could be used??

jonathan

[Jon Brooks]

Ah the good old Digi chestnut.

The good thing about normal radio is you can adjust the squelch to pick up a week signal, you can't with digital.
The signal is either there or it is not.

The other major issue, IMHO, is that marine, like avionics, radio is a safety of life service.
You could not one country digital and another not.
It would need an over night switch over by all using marine radio all over the world.

There are pro's and con's for both types and until the digital pro's are far more than the con's of normal radio there wont be a change.

"if it ain't broke don't fix it!"

IMHO I don't see it changing to digital in my lifetime.

[codprawn]

Couldn't agree more - digital is all or nothing - give me a weak drifting signal over none at all anyday!!!

[Biggles]

Why not have radios that pump out mega power. IE 50 Watts plus.

Anyone know what the coastguard radios output ?

Personally I know that 5 watts is good for a building site type area but its starting to seem that 25 watts for the open sea is starting to leave a lot to be desired.

Is it time to go HF or SSB ?

[Jon Brooks]

Why oh why oh why is everyone convinced that more power is the answer?

Its not!

Any good radio ham or radio engineer will tell you tales of using low power and talking around the world.
I have even chatted to someone on the Cornish cost from here on 5w!!

VHF is line of sight.
The only real and best way to improve range is to raise the antenna height.
This is why a sailing yatch will always have better range than a RIB.

On a RIB you are stuck for choice really.
Most of us, me included, use the Rib Raider antenna, well its not the best in the world but suits the need.

The other point is the more power you need to push out the more battieries you need.
Either that or a very long mains lead!!

25w is fine with the right set up.

[eupa]

My concern in raising the issue in the first place - was when I really needed to communicate- it was nigh impossible in this particular instance. I was out alone, and to fiddle with the radio whilst trying to keep an even keel was
very daunting. Normally I have no problems with my VHF- and that is
the problem. If in emegency you have to relay on vocal wave transmissions with a very limited frequency range- then something must be better.
- this was not a DSC call and was not a may day.

As regards the World switch over to digital - as pointed out by Jon , would it not be better to run digital alongside vhf?

Jonathan

[Channel Ribs]

Originally Posted by eupa

Two weeks ago, I had to use the VHF to talk to control at Nieuwport. What surprised me was that the comms was very poor.

What distance out were you at the time? What antenna and vhf set do you have and when did you last check your wiring, both power and coax?

As mentioned by Jon - in the right conditions you can get fantastic range, the problem there is that you are more likely to need your set when the conditions are poor. Hence the need for a solid arrangement with good wiring.

[Jon Brooks]

There are lots of factors that can upset your VHF use.

Since the windfarm has gone up off of Herne Bay we now get very poor comms with the Thames Coastguard on CH0 in certain location.
Digital and or more power would not solve this.

[JABS]

Originally Posted by Jon Brooks

There are lots of factors that can upset your VHF use.

Jon,

Since you are in this business, I for one would appreciate your input on making the best of a Rib installation. Many of us install the radio ourselves and expect it to be available to save our lives, in the worst case.

Any pointers you can give would be really appreciated, by me at least.

Things like cable size, preventing corrosion, grounding, etc could be of interest??

Thanks in anticipation!


Tony

[Jon Brooks]

Tony,

The best suggestion is not to scrimp on things.

Worth spending a bit more to ensure life in the unit.
There is some great kit on the market there is also some not so great kit on the market!

Use the cable supplied with the unit and the antenna.
Always use good quality antenna connections.

Never cut and re-join co-ax.

Use Vaseline or a like product on connections.
This helps keep the weather out.

Never bodge it, if your not sure ask someone who is.

Cheers

[codprawn]

Originally Posted by eupa

My concern in raising the issue in the first place - was when I really needed to communicate- it was nigh impossible in this particular instance. I was out alone, and to fiddle with the radio whilst trying to keep an even keel was
very daunting. Normally I have no problems with my VHF- and that is
the problem. If in emegency you have to relay on vocal wave transmissions with a very limited frequency range- then something must be better.
- this was not a DSC call and was not a may day.

As regards the World switch over to digital - as pointed out by Jon , would it not be better to run digital alongside vhf?

Jonathan

AS has already been said digital is all or nothing - at least with a poor vhf signal you still have something.

If you want realiable comms everywhere the only way to go is satellite - you can get a cheap Thuraya for about £250 - the calls aint cheap though but in an emergency who cares.......

[mdt]

Originally Posted by codprawn

If you want realiable comms everywhere the only way to go is satellite - you can get a cheap Thuraya for about £250 - the calls aint cheap though but in an emergency who cares.......

ah but is it waterproof ?

[Biggles]

Whilst we are on the subject of waterproofness of radios, a common problem I have come across is that unless you are particular in keeping the knobs washed off the salt gets in and seizes them up.
I have broken some knobs trying to free them off.

Jon,

When it says waterproof does it mean you can put a hose on the face of the radio to wash it down. I tend to spray from a long way to stop water being forced in but this doesn't wash the salt out of all the little crevices !

Nick R.

[eupa]

What distance out were you at the time? What antenna and vhf set do you have and when did you last check your wiring, both power and coax?

As mentioned by Jon - in the right conditions you can get fantastic range, the problem there is that you are more likely to need your set when the conditions are poor. Hence the need for a solid arrangement with good wiring.


Set is state of the art UNIDEN
Radio is checked BEFORE I leave port.( 5/5 receive/send)
Radio mast is a 3 meter whip. on top of the cabin giving sealevel to top mast some 6 meters.

Jonathan.

[codprawn]

Originally Posted by mdt

ah but is it waterproof ?

Plastic bags work great - pretty cheap as well.......

[Jon Brooks]

Originally Posted by Biggles

Whilst we are on the subject of waterproofness of radios, a common problem I have come across is that unless you are particular in keeping the knobs washed off the salt gets in and seizes them up.
I have broken some knobs trying to free them off.

Jon,

When it says waterproof does it mean you can put a hose on the face of the radio to wash it down. I tend to spray from a long way to stop water being forced in but this doesn't wash the salt out of all the little crevices !

Nick R.

Well depends on the make.
I know you can with an Icom and I flush our kit off every evening so I know the Standard Horizon stuff can take it too.

Not sure about the rest.

If it says it is waterproof then it should take a flush off.

[Biggles]

Its Icom stuff.

It was another make I broke.