True John,
I didn't understand you to say that it DOES pickup small birds. My experience is with my R20X Raytheon (JRC) 4kw unit, jumpered to 32 mile range and a few similar size units. I know power makes a lot of difference. I've told the story here about not being able to pickup an ISLAND in the Caribbean with a Sitex 24 mile radar that was 17 miles away. I was looking at the island but never received a return signal. Also vital is Horizontal Beam Width. The smaller the number the better. A small HBW lets the unit do things like differentiate between a tug and its' tow. And all of this doesn't even take into account antenna size. Larger is better. Especially in smaller recreational-sized units. It's something to do with the laws of phyisics. As far as one target looking to be the same size as another, that is an offshoot of science and raster scan technology. Returns tend to look similar sized on the screen. Not until a target is physically larger than the space taken up on the screen does its image begin to show a larger return. (computers) That's why your Alaska cruise ship story is a red flag. I'm certain that you have your set adjusted properly. That just goes with the abilities of the owner.(you) But the list of non-good returns you have is scary. I have yet to have even one of those examples with my R20X. You know,,,,my buddie just bought a JRC. Same model as my R20X only with all the newer controls,,,for $1800.00. Hmmm. He bought it here; http://www.vitmarine.com/index.html
HmmmmP.S. We have a Davis reflector. (somewhere, might have given it away) I couldn't see the sense in it if we can see the other guy.
I didn't understand you to say that it DOES pickup small birds. My experience is with my R20X Raytheon (JRC) 4kw unit, jumpered to 32 mile range and a few similar size units. I know power makes a lot of difference. I've told the story here about not being able to pickup an ISLAND in the Caribbean with a Sitex 24 mile radar that was 17 miles away. I was looking at the island but never received a return signal. Also vital is Horizontal Beam Width. The smaller the number the better. A small HBW lets the unit do things like differentiate between a tug and its' tow. And all of this doesn't even take into account antenna size. Larger is better. Especially in smaller recreational-sized units. It's something to do with the laws of phyisics. As far as one target looking to be the same size as another, that is an offshoot of science and raster scan technology. Returns tend to look similar sized on the screen. Not until a target is physically larger than the space taken up on the screen does its image begin to show a larger return. (computers) That's why your Alaska cruise ship story is a red flag. I'm certain that you have your set adjusted properly. That just goes with the abilities of the owner.(you) But the list of non-good returns you have is scary. I have yet to have even one of those examples with my R20X. You know,,,,my buddie just bought a JRC. Same model as my R20X only with all the newer controls,,,for $1800.00. Hmmm. He bought it here; http://www.vitmarine.com/index.html