I have a question about radar interference with Starlink. This is where I have my Starlink mounted. As soon as I have my radar transmit, my Starlink goes offline. My buddy has as similar boat with similar mount and has the same result. Question is if I lowere the mount to be below the radar will I no longer have the interference or does it need to go above?
Good question. There are several issues here.
Dishy & your radar don’t actually use the same frequencies, but they’re not that far apart. Dishy’s listening to some fairly faint signals, & your radar is shouting really loudly, so it’s getting past the input filters on Dishy.
Your Garmin radar puts out a pretty narrow beam horizontally, but it’s designed to also work with (heeling) sailboats, so it has to put out a pretty wide beam vertically (you should be able to look this up on Garmin’s website, under specifications).
You can try to get Dishy out of your radar’s beam, but if you want them both to work together, they need to be far apart (& no, I’m afraid I don’t have a definitive number for you).
Putting Dishy directly above your radar might work, as there shouldn’t be much radar signal there, but again, further away is better. I know that’s difficult, & again, I don’t have a good number for you.
Finally, one option is to get one of the newer Simrad/B&G/[Navico? – someone else, anyway] “Broadband” radars. They’re all actually the same radar, & they’re not really broadband, but they do work very differently from older radars like yours, & they emit much less power.
Older pulse-type radars send out a short (but very powerful) pulse & then time how long it takes for that pulse to come back. These new radars are transmitting continuously in a “sawtooth” pattern, sweeping up in frequency & then starting over again, continuously sweeping (chirping) their frequency.
There’s actually a 2nd antenna in the dome (which is why these radar domes are higher) that’s continuously receiving. When a signal comes back, it simply beats (mixes) it with the current out-going signal. This produces a sum-frequency (which is very high, & filtered out) & a difference frequency. That difference frequency is exactly proportional to the distance away that the target is.
Somehow, they’re able to make this work with very low power. Apparently, power levels are about that of a cellphone. So they take much less power to run, they can use solid-state transmitters (no expensive klystron tube to burn out), & they’re not dangerous to stand in front of. Yet ours gives us a reflection off rain 10nm away.
Anyway, the lower power output MAY mean less interference with Dishy. I haven’t heard of anyone trying this out (but I’d love to!) This is all just theoretical (I’m an EE, & was a microwave technician in a previous life).
An interesting side-wrinkle to this is that the free OpenCPN navigation program now has a plugin for these radars. You can simply plug the RJ45 cable from the radar into your computer’s network port, & OpenCPN can act as a full radar display, even including MARPA functionality (which shows up as AIS). This can save you thousands for a display. And, of course, OpenCPN allows you to use much better charts than any chart-plotter. And no, I have no financial involvement here at all. I’m just a normal retired cruiser.
Sorry I can’t help more. Good luck!
Radar transmits in a beam that is roughly 12.5 degrees above and below the plane of the radar. Any other rf equipment, such as Starlink, should be mounted outside of this beam. Your photo shows your Starlink almost inline with your radar. No surprise it doesn’t work there. Try raising it up on a temporary extended mount and check again.