You can, but the problem is that the radio chip is not designed for the 27Mhz, then you will generate an huge amount of spurious that will pollute other bands a

You can, but the problem is that the radio chip is not designed for the 27Mhz, then you will generate an huge amount of spurious that will pollute other bands and wasting lot of power. I advise don't do that, just to avoid to interfere with some critical services.