Can someone explain radar to me please...

[Zing]

Technophobe alert!
On our previous boat, we had a clunky old monochrome radar by Furuno. It had a green and black LED screen and you could adjust gain and range and, well, that was about it. Certainly better than nothing but I gather that modern options include all sorts of fancy features, some of which I'm probably not even aware of. Even having the radar overlaid on the same screen as charting and AIS info would be an enormous improvement.

The new boat has no plotter or MFD, so there's a fairly big upgrade to be made there. I've had enough of using phones for navigation.

Of course budget comes in to this. I'm not about to spend £5k on a bunch of new gear. I can find secondhand radomes for as little as $100 (I'm currently in the US) and even these look light years ahead of my old Furuno. But I don't really know what I'm looking at and I'll need to make sure that whatever I find can work with my chosen MFD.

I'm leaning towards an Axiom as my MFD, although I have misgivings about a system that relies entirely on a touchscreen. I'm possibly open to the idea of a more DIY route involving a rugged tablet. But I'm not very techie and don't want to go down a rabbit hole on this.

Any help or suggestions gratefully received!

I think you will get to like radar once you fit it and will find all kinds of uses that you never knew you needed one for. In a busy anchorage I have it on at night and can check on other boats dragging and my swing and my dragging all from my wifi link in bed. Indispensable in fog or at night and for working out what the non-AIS boat is up to. Better for confirming accurate boat positions - AIS reporting is sometimes not frequent or accurate enough.

For a sailing boat I’d go solid state for the power saving. Consider Furuno. It has an advantage in allowing a radar connection to TimeZero software, the best PC plotter software IMHO. Or go Navico, you can do the same but with O-CPN, which is a cheaper, but not quite as good an alternative. Ray is fine too, but I think only a tablet link? I have no experience of Garmin.

You probably don’t need to worry about touch screens, at least they are fine even when wet in my experience with Furuno and B&G.

 

[PaulRainbow]

Update. It looks like a digital radome is out of my budget after all. I was under the impression that anything starting with the letters 'RD' was digital. In fact the needs to be a second D after the number. So RD218D would be a Raymarine radome, 2kw, 18", digital.

The ones I've been eyeing up for sub $300 are actually the older analogue model, which I don't believe is compatible with a brand new Axiom MFD.

This leaves me in a bit a quandary. I don't have the budget to just buy everything new. The Axiom on its own was pushing it. But given that it would also address the WiFi requirement, I thought it was worth paying for.

If I was to snap up one of these very tempting cheap radomes, I'd have to pair it with an already obsolete MFD. That doesn't sound that great an idea, and leaves me needing a separate WiFi module.

Argh. It was all looking quite achievable. I should have known it was too good to be true!

Buy the Axiom and wait until you find a radome in budget. I did post a list of compatible ones earlier.

 

[PaulRainbow]

I think you will get to like radar once you fit it and will find all kinds of uses that you never knew you needed one for. In a busy anchorage I have it on at night and can check on other boats dragging and my swing and my dragging all from my wifi link in bed. Indispensable in fog or at night and for working out what the non-AIS boat is up to. Better for confirming accurate boat positions - AIS reporting is sometimes not frequent or accurate enough.

For a sailing boat I’d go solid state for the power saving. Consider Furuno. It has an advantage in allowing a radar connection to TimeZero software, the best PC plotter software IMHO. Or go Navico, you can do the same but with O-CPN, which is a cheaper, but not quite as good an alternative. Ray is fine too, but I think only a tablet link? I have no experience of Garmin.

You probably don’t need to worry about touch screens, at least they are fine even when wet in my experience with Furuno and B&G.

Furuno is OK, expensive though

 

[Dockhead]

Update. It looks like a digital radome is out of my budget after all. I was under the impression that anything starting with the letters 'RD' was digital. In fact the needs to be a second D after the number. So RD218D would be a Raymarine radome, 2kw, 18", digital.

The ones I've been eyeing up for sub $300 are actually the older analogue model, which I don't believe is compatible with a brand new Axiom MFD.

This leaves me in a bit a quandary. I don't have the budget to just buy everything new. The Axiom on its own was pushing it. But given that it would also address the WiFi requirement, I thought it was worth paying for.

If I was to snap up one of these very tempting cheap radomes, I'd have to pair it with an already obsolete MFD. That doesn't sound that great an idea, and leaves me needing a separate WiFi module.

Argh. It was all looking quite achievable. I should have known it was too good to be true!

I personally would far rather have an obsolete radar, than no radar at all.

The obsolete MFD's are not that bad (so long as you don't go all the way back to the pre-AIS era), and they are cheap as chips. If I were you, I would buy someone's older kit with matched MFD and radar, and save my pennies until I could buy a new set.

The previous generation of Raymarine digital radars seems pretty cheap. Here's one on FleaBay for 800 squids or best offer: Raymarine RD418D 4kw Digital Radar Radome - E92130 | eBay UK.

You could use a used E-series MFD with that.

That would seem to be a very good, cheap solution.

 

[dunedin]

……. In a busy anchorage I have it on at night and can check on other boats dragging and my swing and my dragging all from my wifi link in bed. ….

Wow, doesn’t that drain the batteries having radar transmitting plus MFD on all night?
Our instruments are all switched off to save battery as soon as anchor goes down.
Radar generally gets switched on 3 or 4 times a year (when sailing 100 or so days a year).

 

[Sea Change]

The previous generation of Raymarine digital radars seems pretty cheap. Here's one on FleaBay for 800 squids or best offer: Raymarine RD418D 4kw Digital Radar Radome - E92130 | eBay UK.

You could use a used E-series MFD with that.

I think I could use an Axiom with that too, no?

That specific listing isn't any use to me by the way since I'm currently in Rhode Island.

 

[Roberto]

the rare occurrences like interference patterns, fake returns due to ducting that you may see once per year etc.

I once had the 360deg black circles caused by excess return, nearing a few huge ships at anchor. It s also a useful reminder to zoom in on the chart plotter to check the actual ship size WRT its standard AIS icon size.

I personally would far rather have an obsolete radar, than no radar at all.

Absolutely, I have a stand alone very old monochrome Furuno (I have no MFD, just opencpn), don't know if it ''saved my life'' but on quite a numer of occasions it has been by far the most useful piece of electronics onboard, even more than GPS when there were no charts to plot a position

 

[PaulRainbow]

I think I could use an Axiom with that too, no?

Check the list in the link i posted.

 

[Sea Change]

Check the list in the link i posted.

If I'm reading that correctly then yes, RDXXXD will work with an Axiom.

Funnily enough eBay has turned up an RD418D right here in the town where I'm anchored, and being sold by an established marine electronics company. With the current exchange rate it's a bit over £600.
The only one I can find cheaper is the 24" which seems very large for the space I have in mind.

Talking of mounting the thing... why are the mast mounts so crazily expensive? I know it has to be robust but is there something I'm missing? The going rate is about $300 for a new one.

If I don't mount it on the mast, my other option is to get rid of my wind gen and put the radar on the pole. I'd imagine it wouldn't be too hard to fabricate a suitable mount for that.
Pros and cons?

 

[PaulRainbow]

If I'm reading that correctly then yes, RDXXXD will work with an Axiom.

Funnily enough eBay has turned up an RD418D right here in the town where I'm anchored, and being sold by an established marine electronics company. With the current exchange rate it's a bit over £600.
The only one I can find cheaper is the 24" which seems very large for the space I have in mind.

Talking of mounting the thing... why are the mast mounts so crazily expensive? I know it has to be robust but is there something I'm missing? The going rate is about $300 for a new one.

Typical boat price, inflated.

If I don't mount it on the mast, my other option is to get rid of my wind gen and put the radar on the pole. I'd imagine it wouldn't be too hard to fabricate a suitable mount for that.
Pros and cons?

You'd have to be careful with obstructing the forward "view" and it's heavier. You only need a flat plate welding to the pole to mount it.

 

[Sea Change]

Typical boat price, inflated.

You'd have to be careful with obstructing the forward "view" and it's heavier. You only need a flat plate welding to the pole to mount it.

I see plenty of yachts with the radar mounted on a pole at the stern. It seems an easier option, without any chance of getting snagged. I'll have to read up about how much of a compromise it is having the mast ahead of the radar.

Another location I've seen, generally on larger boats, is a bracket fitted on top of a spreader. But this is probably a whole discussion in itself.

 

[Zing]

Wow, doesn’t that drain the batteries having radar transmitting plus MFD on all night?
Our instruments are all switched off to save battery as soon as anchor goes down.
Radar generally gets switched on 3 or 4 times a year (when sailing 100 or so days a year).

Not much. It is on, but the MFD screen is put in sleep mode, so the main consumer is off and the radar is similarly in sleep, so almost off, but it will do a full sweep in only a few seconds on waking. I have quite a lot of battery anyway and capacity is negligibly impacted.

 

[Dockhead]

Wow, doesn’t that drain the batteries having radar transmitting plus MFD on all night?
Our instruments are all switched off to save battery as soon as anchor goes down.
Radar generally gets switched on 3 or 4 times a year (when sailing 100 or so days a year).

I do as Zing does.

I never shut my instruments down in principle in case I have to make a quick exit for whatever reason. Likewise key is always in the ignition at anchor, even if I'm off the boat.

My current radar needs about 20 watts, or less than my old pre-LED anchor light. My previous 4G radar used 17 watts. This was not a challenge even with our old lead battery system, now with 13.4kWH of lithium it's not noticeable in the least.

I find the radar fantastically valuable in the anchorage. Your eyes are not a good judge of distance; the radar is, so it's really useful in picking a spot in a crowded anchorage.

I sometime use the zone alarms to wake me up if something gets too close in the night.

It's great, as Zing says, for seeing whether other boats are dragging or not.

 

[Dockhead]

If I'm reading that correctly then yes, RDXXXD will work with an Axiom.

Funnily enough eBay has turned up an RD418D right here in the town where I'm anchored, and being sold by an established marine electronics company. With the current exchange rate it's a bit over £600.
The only one I can find cheaper is the 24" which seems very large for the space I have in mind.

Talking of mounting the thing... why are the mast mounts so crazily expensive? I know it has to be robust but is there something I'm missing? The going rate is about $300 for a new one.

If I don't mount it on the mast, my other option is to get rid of my wind gen and put the radar on the pole. I'd imagine it wouldn't be too hard to fabricate a suitable mount for that.
Pros and cons?

I would put it on the mast, if I were you.

Pole mounts cause trouble if they are not perfectly rigid (which is hard, or rather, expensive to achieve), they are not as high, and don't have as good a view ahead. Wind generator poles are not usually rigid enough; you will want a braced one like the ScanStrut.

A third variant is a backstay gimbal mount.

I don't think any decent method of mounting it is going to cost less than $300.

Mast mount has another drawback, however -- if you are keel-stepped it can be hard to pull the radar cable without unstepping the mast.

 

[Sea Change]

I would put it on the mast, if I were you.

Pole mounts cause trouble if they are not perfectly rigid (which is hard, or rather, expensive to achieve), they are not as high, and don't have as good a view ahead. Wind generator poles are not usually rigid enough; you will want a braced one like the ScanStrut.

A third variant is a backstay gimbal mount.

I don't think any decent method of mounting it is going to cost less than $300.

Mast mount has another drawback, however -- if you are keel-stepped it can be hard to pull the radar cable without unstepping the mast.

The existing pole is 2" stainless with bracing. It's absolutely solid.
If it can withstand the existing Silentwind 400 turbine buzzing away on it, I'm pretty sure it will cope with a non moving 18" radome.
Height above the waterline is 3.5m

I will obviously need to make/find some way of adapting the pole to take the radome, but I don't think that will be as difficult/expensive as a mast mount.

If I go for a mast mount, should it go just above the staysail?

 

[Dockhead]

The existing pole is 2" stainless with bracing. It's absolutely solid.
If it can withstand the existing Silentwind 400 turbine buzzing away on it, I'm pretty sure it will cope with a non moving 18" radome.
Height above the waterline is 3.5m

I will obviously need to make/find some way of adapting the pole to take the radome, but I don't think that will be as difficult/expensive as a mast mount.

If I go for a mast mount, should it go just above the staysail?

You can put it wherever it won't get fouled by halyards or sails.

Mine is at the level of the first spreader, 10m above the waterline, and a couple metres below the the top of the inner forestay. My mast is 23 metres.

 

[Sea Change]

Just been offered an E97 for less than a third the price of a new Axiom.
Any thoughts? @PaulRainbow ?

 

[PaulRainbow]

Just been offered an E97 for less than a third the price of a new Axiom.
Any thoughts? @PaulRainbow ?

Could be 10 years old........

 

[Sea Change]

Could be 10 years old........

It's from 2017. Being replaced because it was linked to another plotter which got damaged, and they had to then replace both with new Axioms.

It's tempting because it's still compatible with a digital radome, and it comes as standard with both touchscreen and physical controls.

 

[dunedin]

Just been offered an E97 for less than a third the price of a new Axiom.
Any thoughts? @PaulRainbow ?

That will be an e97 (lower case) very different from previous E range (upper case). We have has both.
We currently have an e7 and an e127 linked to our radar (via wifi).
Decent units and plenty of functionality for everything you need.
Our e127 was bought second hand as needed same generation as other kit.

Check
- installed software version against Raymarine website - want to have the latest software (though that was 5+ years ago)
- the microSD card reader still works as some failed, and i believe parts are limited