copied from the Internet:
From: levin@cosmic.physics.utah.edu (Chris Levin)
Subject: Alinco DR-600 Mods
Organization: Cosmic Ray Physics Group, University of Utah
 
I just got the info on how to modify the Alinco DR-600.  I have
activated these mods and they seem to work fine.  Here they are:
 
Mod 1 - Activate 108 - 142 MHz and 810 - 998 MHz Receive
--------------------------------------------------------
 
Remove head unit from radio and open it up.
 
Inside you will see a red and blue wire.
 
Cut the red wire.
 
Open the main unit and attach a wire to CN-205.  This will be
your antenna for 810-998 MHz.
 
Close everything up.
 
Reset the CPU by holding down the FUNC key while you turn the
radio on.
 
To use:
The VHF key toggles between 108-142 and 2m.  This toggle
only works in VFO mode.
 
The UHF key toggles between 810-998 and 70cm.  This toggle
only works in VFO mode.
 
 
Mod 2 - Extened tx/rx on 2m and 70cm
------------------------------------
 
Remove head unit from radio and open it. (2 screws on back)

Inside you will see a red and a blue wire.

Cut the blue wire.

Put everything back together.

Reset the CPU by holding down the FUNC key while you turn
the radio on.
 
You can now transmit and receive on the following freqs:
130-174MHz and 400-517MHz
 
Be carefull!!!!! You can now transmit outside of the HAM
bands.  Don't do this!  If you do you WILL get caught and
the FCC loves those $10,000 fines.
 
NOTE:  I take no responsibility for these modifications.  If
you blow up your radio it is not my fault.  
 
Chris Levin
levin@cosmic.physics.utah.edu
=========================================================================
Note: I haven't tried or verified this, proceed at your own risk.  WA2ISE
/EX
