The IC-275 have capability to cover 138 - 174 MHz and the IC-475 has capability to cover 430 - 450 MHz. Because of hardware restrictions they might not be fully up to specifications in all of the band, but an extended range can be interesting for e.g. use with a transverter. It seems that the IC-275 has a parallel wide band preamp, that can be switch via the WBT pin on RF-YGR PCB.
In the European versions the transceivers are wired for 1750 Hz repeater call, and they have no CTCSS capability. The transceivers have a built-in CTCSS encoder, so these functions can be restored.
Both of these version dependent functions can be set by the diode matrix: D20 - D24 in the logic unit. I do not know the exact mapping, but a lot can be derived from studying the different frequency ranges and the diode matrix coding table found on the schematic diagram.
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