.... The advantage of a radar interfaced to a multi-function display is that you can overlay the radar signal on the chart. That is a VERY nice function.
.... Those "broadband" radars ... are far superior to magnetron based radars at short ranges, but not as good at longer ranges although they are much better now than even two years ago.
...Broadband radars are safer than magnetron radars since they transmit about 1,000 times less power.
At the risk of being argumentative, I would take issue with these assertions. Some of it is opinion/preference, and some of it is factual.
1) Radar overlay vs separate screen. This one is heavily slanted towards the opinion/preference category, but over time I have come to prefer separate chart and radar screen. Here's an
article explaining why for anyone who is interested.
2) Broadband is superior at close range. In my experience I have found this to not be true in any practical way. I owned a Simrad 4G for a while and it's good at close range. That's true. It is also inferior at distances, but that's another topic. But....I have found both the Furuno DRS4D and the Furuno 1835 radars (both 4kw domes) to be just as good, if not better than the 4G. Yes, it's true that the pulse radars have a 20m blind spot around the boat when on close range. But when did you need to use your radar to see something 20m away that you couldn't see with your eyes? Fog, day, or night. 20m is the distance between fingers on a dock. Is that really what you want to buy your radar for? It's a radar, not a backup camera. And beyong 20m I have found the 4kw pulse radars to be as good or better in all situations. In short, I found no situation - zero - where the 4G outperformed a 4kw furuno pulse radar.
3) The whole low power things with 3G and 4G radars is so blown out of proportion and context. In reality, the difference is so negligible that it really doesn't matter. Here are the facts:
- Yes, a 4kw radar pulses at 4kw. But on short range those pulses last for 80 nano seconds. That's 80 billionths of a second. And they repeat 2100 times per second. The resulting average power is 670 milliwatts. To put this in perspective, your cell phone is 500 milliwatts, and you hold it directly against your brain. A 4G radar transmits continuously at 165 milliwatts. Yes, that is less that a 4kw pulse radar, but it's 4x less, not 1000 times less.
- Let's look at it another way. The regulated safe distance power level that radar safety is specified to is 100mW/m2. That's 100 milliwatts per meter squared, so it's a density of power over an area. The safe distance for that power level for a 3G or 4G radar is 0m. That's good. But let's take a look at the same safe distance for a handful of Furuno pulse radars (BTW, I'm highlighting Furuno only because that's the other radar that I'm most familiar with, and for which I have ready access to the specs.)
DRS4A 4kw open array; safe distance 0m
DRS6A 6kw open array; safe distance 0m
DRS2D 2kw dome; safe distance 0m
DRS4D 4kw dome; safe distance 0.1m (4")
1835 4kw dome; safe distance 0.1m (4")
So as you can see, several of the pulse radars are equally safe if you are kissing it, and others are just as safe if you stand back a whopping 4".
If you still prefer a broadband radar, just pick it for real rather than imaginary reasons. Yes, they turn on right away. In some instances that might be good. In other is just doesn't matter. Furuno has done some really nice things with their NXT radar like automatically coloring hazardous targets red. That seems like a real and useful benefit.