There's definitely a H/W mod option for the VX-8r for MARS type use.

http://www.kb2ljj.com/data/yaesu/VX-8R.htm

This claims to document a soft mod that's accessible via magic key combinations but I don't know that it necessarily involves memory that's exported in a clone

On Fri, Apr 8, 2011 at 6:51 AM, Dan Smith <dsmith@danplanet.com> wrote:
> Also as I noted in my original msg to Dan, the software mod
> that worked through the backdoor on the VX-8R apparently has
> been removed from the VX-8DR.

I had one of the original VX-8 radios and it didn't have the magic
middle block that the 5,6,7 radios do, just for what it's worth.
However, it's entirely possible that the switches are buried elsewhere.

--
Dan Smith
www.danplanet.com
KK7DS

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