Interferance

Hi all, i am in need of some help, i have a pair of mitex vhf radios that are performing very well but i have come across a problem, i am using the mini mag mount that mitex supply and am transmitting and receiving around 8 miles no problem. But when i am in my tractor as soon as i turn the ignition on i get terrible interference and it will cut out the incoming signal. Is there anything i could try to remedy this? As i said i dont even need to start the engine it is a soon as i turn ignition on and it powers up the dash and all electronics.

Many thanks in advance,

Interference can be caused by a lot of things, such as other electronic devices, poorly grounded or overloaded circuits or an alternator. What other devices besides the radio are also installed in your tractor?