What is the range of a handheld vs an integrated DSC VHF?

[TBillings]

I've been trying to figure this out, but to no luck. I understand that an integrated DSC VHF will have a longer range (and by integrated, I mean one that uses the VHF antenna in the mast), but what's the range on a handheld?

Long story short, I'm planning a trip around the Farallon Islands off of San Francisco Bay. But I want to make sure I have all the necessary safety equipment first (ePirb, Liferaft, and DSC). The nearest Coast Guard station is around the Gate, shielded by a mountain. Would the DSC signal still get through if we're out by the islands 23 miles offshore? Would a handheld VHF DSC still make it through?

And if I have the DSC, would I even need an ePirb or is that overkill?

[Sandero]

VHF is line of sight... and then consider the power output.

[Dockhead]

Originally Posted by Sandero

VHF is line of sight... and then consider the power output.

The antenna,vandalism cabling/connections to the antenna, is more important than power output.

I once got a "weak, but readable" radio check from Solent Coast Guard, from just outside Cherbourg Harbor, 60 miles away. Using 1 watt of power. But with a very high quality, well installed antenna, mounted 23 meters above the water.

Handhelds have plenty of power - 5 or 6 watts. But crappy, tiny antennae, low to the water. They are made for short range communication, and I would not recommend to the OP using a handheld for his purpose, unless it's really impossible to get his hands on a fixed mount radio. He might consider acquiring a PLB for use in case of a real emergency.

Sent from my D6633 using Cruisers Sailing Forum mobile app

[TBillings]

Well, no, I have to buy one or the other, so I can very easily get a fixed-mount DSC option. I think they're only like a hundred or so.

But the next question is... do I just plug my regular old coaxial VHF antenna into it, or does it use something super fancy?

[44'cruisingcat]

It's not real far. We couldn't be read from our backyard, which was about 6 miles away from a friend's boat, which we could quite easily see. We were about 20 metres above sea level too. We could hear him, he couldn't hear us.


Our boat VHF can usually be read from 30 miles or more, and we've received from coast guard stations 300 miles away!

[Dockhead]

Originally Posted by MatthewDurst

Well, no, I have to buy one or the other, so I can very easily get a fixed-mount DSC option. I think they're only like a hundred or so.

But the next question is... do I just plug my regular old coaxial VHF antenna into it, or does it use something super fancy?

OK, in that case, definitely go fixed mount. Handheld VHF is for different purposes and is not a substitute for your fixed mount VHF.

Your old antenna might work ok. You can install the new radio and then test it. It might work acceptably, but it is unlikely to work well, however, and the older it is, the more unlikely. It is advisable to install a new antenna with good cabling if you can afford it, and if it is feasible to pull the cable (sometimes can't be done with the mast up).

It's not all that expensive. Maybe $100 for a decent antenna. Use good low loss coax cabling with the connectors installed by someone who really understands it. If you can't pull new cable, you might be ok by installing new connectors, depending on the age and condition of the cable.

The antenna is more important than the radio, so if your budget is limited, better a cheap radio and good antenna, than vice versa. VHF DSC is going to be your primary way to get help in case of an emergency, in coastal areas, so if you can possibly afford BOTH a decent radio and a good antenna setup, then this is really advisable.

[S/V Alchemy]

The greatest range I've ever had on my handheld (SH HX850) is about eight miles, and more like six for reliable TX. The greatest on my VHF at 25 W was at night around 35-38 NM. AIS target, by contrast, can be seen beyond that with a mast-top antenna, so presumably could a DSC Mayday.

[estarzinger]

The OP should get a 25 watt fixed radio. But he should be aware that it can be difficult even with the best VHF set-up to communicate from the Farallon's back to the mainland. This was documented in the Low Speed Chase Incident. The USCG, with their good receive equipment, was able to hear VHF from the better radios in the fleet, but the race committee was not able to hear much of anything with their typical boat gear.

On the more general question, I have always been interested and somewhat puzzled by the 'vhf range' question. On the one hand people say it is all about radio line of sight and that you can hear a 1 watt signal back from the moon. But on the other hand, we all know that the low power setting on our radios does in fact seriously cut their range (even using the same masthead antenna) and handhelds typically have really limited range. So, it has always seemed to me that it is in fact not 'all about line of sight' and that power (including antenna gain) does in fact matter significantly to effective transmit range. But I have never seen a range calculator that captured this.

[Stu Jackson]

The CG at Fort Baker, tucked behind the hills north of the bridge, is for the 44 foot big guy rescue boats. The main antenna for CG and VTS is NOT there or else it would be useless for working out to sea. I don't know personally where it is, but I'm sure Kimball Livingston's book Sailing The Bay mentions it. I've "done" The Farralones twice. I have both a HH and a fixed mount. I run the HH all day long, scanning 16, 14 & 12 (you do know what they do, right?). Never had any reception issues out there. Never had a need to call, either. Your boat, your choice on DSC or eprib. Two different types of safety equipment. There are so many freighters and pilot boats and fishing boats out there, as well as other recreational vessels, I've never felt that I was out of touch. It's only 25 miles, but if you were concerned about always being able to raise the CG, get a fixed mount that is either accessible from the cockpit either from where it is mounted or on a swing arm, or get one with a ram mike. My gut reaction is you're overthinking this, although safety equipment for comms is always a personal decision.

Have a great trip. Don't go before April.

[a64pilot]

For me one of the hand helds is for putting in the dinghy to call the kids and tell them Supper is ready, that kind of thing, although they do work well for calling bridges as your quite close to the bridge. But that is about it.

[Cheechako]

I've found handhelds to be very limited. We used two for talking to each other while one was on the beach or ashore in town. Often not useable even just a mile or two away. Most anything will impede the signal.

[bobmcd625]

Its all about the height of the antenna. I just looked up in my VHF Hanbook (published by the British RYA) and found this: The distance to an antenna's VHF horizon (in miles) is about 3x the square root of its height in meters. The provide a little table
Antenna Height: 1 m (3 ft), VHF Horizon 3 miles
Antenna Height: 4 m (13 ft), VHF Horizon 6 miles
Antenna Height: 16 m (50 ft), VHF Horizon 12 miles
Since the Faralons are about 25 miles from shore you'd better get the fixed mount unit and get that antenna up as high as possible.
The good news is that there may be sailing boats or ships within range and the height of their antennas will save you bacon. That is that a sail boat of similar size would get your signal within 24 miles. A ship within 30 miles would pick it up.
Go to West Marine and talk to David. He'll help you out. Good luck. Should be a great trip.

[colemj]

If you are only concerned about the CG, their antennas are generally very high, powerful and sensitive - some directional. Most likely you would be able to communicate at that distance with them.

Mark

[bobmcd625]

Good point. I should have looked further down the table. They show that the sail boat (50 ft mast) would reach a CG station 42 miles away. They also show that the hand held only 3 ft above the water would reach a CG station 33 miles away.

[Dave22q]

I just finished researching some radios before replacing mine. Generally the hand helds claim ranges of 1 to 5 mi while the fixed mount antenna on the mast claim 25 or so. Now if you attached your hand held to a mast antenna you could probably get more range. The key variables are wattage and mast height and the majority of model appear to have the same power.