Which frequency do you DF in your vehicle?

We are considering the development of a more turnkey antenna product. Before we can work on any details, we would like to understand the frequency that is of most interest during mobile/vehicle-mounted operations. Please provide the frequency, frequencies, or frequency range. Thanks!

For me its 27 to 470 MHz. In sweden we dont have Personal mobile bands above 470 MHz. weather resistance is important.

US amateur 2m and 70cm bands, both for repeater interference and DF contests.

I try to maintain my DF setup 24/7, so weather resistance is important.

I have been using TV channel frequencies to test with because I know where they are transmitted.

Generally 400-512mhz is my regular requirement for searching. :face_with_monocle:

I agree with the others on weather resistant… Definitely something more sealed so it could stay on the vehicle in rain :cloud_with_rain:.

Most of my past testing/operations have been in the 402~460 Mhz bands. I have recently started testing in the 140~170 Mhz bands. What I like about this system, is the ability to relocate the antennas to cover different bands/frequencies.

I’m not sure a “turnkey Antenna” will cover the same range as the SDR’s?

US amateur 2m and 70cm bands, both for repeater interference and DF contests every weekend.

121.5, 121.775, 243, 350, and between 406.0-406.1 are our primary frequencies we use for SAR, but 800 and 900MHz are used for some life-alert type devices for tracking/GPS which would be handy.

I know this was mentioned above by someone else, but I also say that the US amateur 2m (144-148mhz) and and 70cm bands (420-450mhz) would be a priority for me.

The GMRS part of the UHF spectrum is also useful (462-467 Mhz).

28, 52, 146 and 440 MHz

When you guys are doing these vehicle DF adventures, do you know where a transmitter might be and tune it to that frequency? Or are you all just driving around waiting for stuff to show up in the Android App?

For me, i just DF if there is for example a pirate station. And usually here. A pirate that disturbe HAM radio or commercial, are usually also active on CB radio. So i lissen, and document before i go out.

Where do you find the stations to listen and document before going out on a drive? I would love to be able to test the KrakenSDR with multiple emitters but I am having trouble finding resources to use for testing. I am in a semi-rural area and ended up testing a 553Mhz frequency because it was blasting television channel data.

Any advice?

My interest lie of course in the 2M and 70CM bands in the USA. However, my real interest for putting DF gear into practice is on the public safety bands. VHF, UHF, 700 and 800 MHz. As well as ELT frequencies as I have had to DF those a couple times.

While an antenna alignment tool would be handy, I would like to see the user interface simplified. There are too many settings to be honest.

For us it’s 400-500 MHz and 700-900MHz. We have used 700 MHz P25 trunking control channels to test. Another guy here locally has a pretty nice setup he designed.

The integration of an additional SDR that would receive the audio/data from the target frequency would be great.


P25 Public Safety 700-900MHz

For me, I know the freq of interest, and most of the time I know the general area of the xmitter. But there have been a few times where I was surprised by the location.

700-900mhz public safety range.