PHP Warning: Use of undefined constant VBA_SCRIPT - assumed 'VBA_SCRIPT' (this will throw an Error in a future version of PHP) in ..../includes/functions_navigation.php(802) : eval()'d code on line 1 Garmin HD radar antenna versus non HD???
Even though it's got nothing to do with your actual question....I used to have my 18hd hooked up to a 4010 and it was a pretty sweet little unit. Could see everything that was out there including small boats, birds and markers with a bit of tuning so no complaints here with the 18hd. I've now got it hooked up to a 7012 and with the bigger screen and better resolution it's got just that bit better and more 'trustworthy' in times of low visibility.
I have the non hd connected to a 4210 and it performs the same as muddy describes. I have a feeling but not 100% that the 4000 series do not support hd. It is a great feature that gives that you that extra confidence.