Rum_Pirate
Well-Known Member
What range (line of sight and all that) should a 5 watt handheld VHR marine radio (eg a Standard Horizon HX370) have?
1 miles
3 miles
5 miles
or more?
1 miles
3 miles
5 miles
or more?
VHF range
- Thread starter Rum_Pirate
- Start date
William_H
Well-Known Member
I have seen a friend's hand held with 6inch antenna work OK over about 5 miles of water to a base station. It was no good on low power.
Much depends on getting the antenna as high as possible and vertical.
In ordinary use h/h to h/h a mile would be good.
olewill
Much depends on getting the antenna as high as possible and vertical.
In ordinary use h/h to h/h a mile would be good.
olewill
Rum_Pirate
Well-Known Member
I also have a Ray Marine - Ray 45 VHF MARINE RADIO which is a totally waterproof VHF radio.
All Channel Scanning 1 or 25 watt output power 16 plus key quickly gets to channel 16 or preset priority channel Tri-watch scans working channel, priority channel and weather channel. Waterproof to U.S. Coast Guard CFR-46 standards On-Mic controls for ease of use Large Backlit LCD display External Speaker Jack
I must remember to install it. /forums/images/graemlins/blush.gif
PS Would this be legal for use in the UK ?
All Channel Scanning 1 or 25 watt output power 16 plus key quickly gets to channel 16 or preset priority channel Tri-watch scans working channel, priority channel and weather channel. Waterproof to U.S. Coast Guard CFR-46 standards On-Mic controls for ease of use Large Backlit LCD display External Speaker Jack
I must remember to install it. /forums/images/graemlins/blush.gif
PS Would this be legal for use in the UK ?
ccscott49
Well-Known Member
Yep completely legal, probably a switch somewhere or a command to switch from US channels to European. Check the handbook.
Channel Ribs
Well-Known Member
[ QUOTE ]
What range (line of sight and all that) should a 5 watt handheld VHR marine radio (eg a Standard Horizon HX370) have?
[/ QUOTE ]
I use a Horizon 370 on a daily basis...
Good contact with other handhelds is up to a mile on high power, best ever was 3.5nm. To fixed station the range is very good, over 5 miles.
What range (line of sight and all that) should a 5 watt handheld VHR marine radio (eg a Standard Horizon HX370) have?
[/ QUOTE ]
I use a Horizon 370 on a daily basis...
Good contact with other handhelds is up to a mile on high power, best ever was 3.5nm. To fixed station the range is very good, over 5 miles.
Salty John
Well-Known Member
It's legal in the UK if it has a CE mark. Some do not - the manufacturers often have a European version and a US/rest of the world version.
Refueler
Well-Known Member
Range is dependent mainly on 4 factors :
1) Height of sender antena and clear path
2) Height of receiver and clear path
3) Weather at time
4) Night / Daytime atmospheric effects.
If sender and receiver were standing on hills with no interuption between, good clear day with low humidity, no other RF gear around - you'd likely be amazed at range achieved. But given that average HH is used in cockpit where antena is at times dropping below unobstructed line to receiver - then its range is significantly reduced.
TBH - it's not fair to state an actual range because of effects and other. I've had good contact from Hayling Island to others near Cowes in Solent ... that's a reasonable distance that usually you would expect a Fixed set to be used. Other times I've been outside a marina and called and had no reply .. changed to fixed set and immediate reply. On asking whether they heard first calls .. answer no.
I've managed conversations in Stockholm Archipelago with numerous islands between myself and other - using HH's ... guy on his boat has moved a short distance and signal lost .. changed to fixed.
Best way to consider it is line of sight and visual range. It also seems that a HH of 2W (like my cobra's) are not so disadvantaged as you'd think and usually achieve similar to my works ICOM's / others at 5W ...
If you want range - there is no substitute for antena at top of mast. If you want portability in a HH - then you have to accept that often you are not going to have contact till reasonably close.
1) Height of sender antena and clear path
2) Height of receiver and clear path
3) Weather at time
4) Night / Daytime atmospheric effects.
If sender and receiver were standing on hills with no interuption between, good clear day with low humidity, no other RF gear around - you'd likely be amazed at range achieved. But given that average HH is used in cockpit where antena is at times dropping below unobstructed line to receiver - then its range is significantly reduced.
TBH - it's not fair to state an actual range because of effects and other. I've had good contact from Hayling Island to others near Cowes in Solent ... that's a reasonable distance that usually you would expect a Fixed set to be used. Other times I've been outside a marina and called and had no reply .. changed to fixed set and immediate reply. On asking whether they heard first calls .. answer no.
I've managed conversations in Stockholm Archipelago with numerous islands between myself and other - using HH's ... guy on his boat has moved a short distance and signal lost .. changed to fixed.
Best way to consider it is line of sight and visual range. It also seems that a HH of 2W (like my cobra's) are not so disadvantaged as you'd think and usually achieve similar to my works ICOM's / others at 5W ...
If you want range - there is no substitute for antena at top of mast. If you want portability in a HH - then you have to accept that often you are not going to have contact till reasonably close.
wotayottie
Well-Known Member
have a friend who is a bit nerdy and interested in ham radio vhf competitions. he regularly contacts people 500 km away using 10 watts on approximately the same frequencies as the marine VHF ones - its all down , as refueler says, to things like atmospherics, height of antenna, type of antenna etc. for example we sometimes hear French boats off their channel coast here in south wales.
one thing that is largely irrelevant, assuming they are working to spec, is the make of the radio. 5 watts from an icom is exactly the same as 5 watts from a cheepo.
one thing that is largely irrelevant, assuming they are working to spec, is the make of the radio. 5 watts from an icom is exactly the same as 5 watts from a cheepo.
MoodySabre
Well-Known Member
Article in this months issue of ST on this.
Height of transmitting and receiving aerials is crucial. Distance is 2.25 x sq root of aerial height (in metres). Add the figures for sender and receiver together. Article didn't say at what output though!
Increased distance to a fixed station is prob due to extra aerial height compared to a boat.
Height of transmitting and receiving aerials is crucial. Distance is 2.25 x sq root of aerial height (in metres). Add the figures for sender and receiver together. Article didn't say at what output though!
Increased distance to a fixed station is prob due to extra aerial height compared to a boat.
Bilgediver
Well-Known Member
It's legal in the UK if it has a CE mark.
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I think you will find this is not so!!
The CE mark only says it wont kill you if you chew the paint or chop your fingers off....
Transmitting equipment has to meet the UK approvals for such ( MPT 1252 ) and this is an additional requirement. Usually this is denoted by the Model number as well as a reference on the label.
CE is a general requirement for Europe regarding safety however there are different requiremens such as ATIS there for inland and no ATIS here.
******************************************
I think you will find this is not so!!
The CE mark only says it wont kill you if you chew the paint or chop your fingers off....
Transmitting equipment has to meet the UK approvals for such ( MPT 1252 ) and this is an additional requirement. Usually this is denoted by the Model number as well as a reference on the label.
CE is a general requirement for Europe regarding safety however there are different requiremens such as ATIS there for inland and no ATIS here.
Salty John
Well-Known Member
That's correct.
In this case I meant specifically if his Raymarine 45 had a CE mark it would have been intended for the European market and would, therefore, comply. A bit of a short cut!
In this case I meant specifically if his Raymarine 45 had a CE mark it would have been intended for the European market and would, therefore, comply. A bit of a short cut!
lw395
Well-Known Member
If you can achieve actual line of sight, the theoretical range is enormous, astronomical in fact. 10,000km roughly! Space vehicles sent to Mars etc do not have much power, neither will the comms work if there's anything in the way.
So the limitation is mainly curvature of the earth and other obstructions.
So the limitation is mainly curvature of the earth and other obstructions.
st599
Well-Known Member
Not true. Legal only if it is EU type approved and has a CE mark.
maxi77
Well-Known Member
CE marking is self applied, where as type approval means that the specs have been checked and samples tested to ensure the regulations are met, so type approval is expensive, and every one has CE on either the plastic moulding or plate.
If the model is type approved there will be a list somewhere in the EU with the model number on it.
If the model is type approved there will be a list somewhere in the EU with the model number on it.
maxi77
Well-Known Member
YOu also need to take account of both spreading and attenuation. Your 1 watt on a handheld does not go that fat as it is dissipated by both spherical spreading so that at one mile the power output is now spread over the surface of a hemisphere 2 miles in diameter. Also it has lost energy as it bumps it's way past the atoms ind molecules in the atmosphere.
Of course in space there is almost no attenuation over range so signals do go farther, and if you control the spherical spreading with a directional aerial then enormous ranges can be achieved with little power.
Just to confuse things you can also get surface ducting where the radio waves going upwards get bent back doen to the surface giving much longer ranges than line of sight. This can at times be clearly seen on radar which enjoys the same phenomenon.
Of course in space there is almost no attenuation over range so signals do go farther, and if you control the spherical spreading with a directional aerial then enormous ranges can be achieved with little power.
Just to confuse things you can also get surface ducting where the radio waves going upwards get bent back doen to the surface giving much longer ranges than line of sight. This can at times be clearly seen on radar which enjoys the same phenomenon.
lw395
Well-Known Member
The figure I gave is based on the 'one over R squared' reduction in signal strength due to range- spherical spreading as you term it.
Atmospheric loss is pretty negligible at 160odd MHz, unless there is very heavy rain.
We are usually using diffraction and surface effects beyond the direct line of sight.
GPS Satellites are 12000 miles up and only transmit a max of 50W.
Atmospheric loss is pretty negligible at 160odd MHz, unless there is very heavy rain.
We are usually using diffraction and surface effects beyond the direct line of sight.
GPS Satellites are 12000 miles up and only transmit a max of 50W.
Cantata
Well-Known Member
I have stood next to a CG standing on the clifftop near home, he was talking on his handheld to Thames CG presumably on their Shoeburyness aerial, it was perfectly loud and clear, 16 miles. All across water, clear line of sight.
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