I'm looking to buy a 10 meter antenna for my car but they are all CB antennas, but they sat they can be used on 10-meter band. how do I set up the antenna
for 10 meters.
That's going to depend on the exact antenna you choose. I'd recommend a base loaded antenna with a metal whip. Those are easier to tune outside the CB band than the fiberglass whips.
You'll need to have an SWR meter that covers the 10 meter band, or something like a NanoVNA that will visually show you the antennas resonate point.
You'd usually start by cutting about a 1/4" at a time off the bottom of the whip until you get close to the frequency you want, then cut smaller increments until you have it where you want it.
I'm looking to buy a 10 meter antenna for my car but they are all CB antennas, but they sat they can be used on 10-meter band. how do I set up the antenna
for 10 meters.
I use the Hustler antenna system.. I have a 54" mast with a 10 meter resonator screwed on top. (You can run other bands with other resonators). Works well. The 10m resonator is very broad and covers pretty well all of the 10 meter band.
Besides the Hustler jwt873 mentioned, you can get RM-10 and 11 coils.
I have used a Wilson 1000M mag mount and had the standard 11 meter whip. I had a second, I cut down, tuned to 28.9 MHz.
That whip was about 5 inches shorter. (never measured it, just tuned it for 10 meters.)
I started 1 inch then 1/4 inch until the SWR began going up. that was it, then set the sweet spot with the adjustment.