[hertzian]

I'm going to assume you have a mobile antenna - and the built-in attenuators are just not enough.

RS used to have a variable 20db attenuator, but other options might be to purposely use a less-efficient antenna, coil up a long run of lossy coax such as RG-58 or perhaps a long run of RG-174 coiled up in the trunk.

I'd probably keep the good antenna, and choose a less efficient long run of feedline for the 800mhz stuff, which will still keep losses reasonable at UHF and below.

So the trick here is to find a working combination of built-in attenuator and length of lossy feedline to accomplish the goal. If you get the mix right, you might be able to selectively program the attenuator in for the 800mhz stuff - and along with the lossy coax get enough attenuation to make that band usable again, without adversely affecting the lower bands which won't need any attenuation programmed in, and the line loss not be too much of an issue.

I'm looking at mounting my GRE-made Pro-164 in the mobile too, and am pondering doing this as well in order to help tame the front-end at 800mhz.