All versions are interoperable (1).
| Picture | Version | Markings | Main feature changes |
 |
Version 7
Released: April-2012
|
Bottom label: RRC-1258MkIIs V 7 Web info page:
|
JMP-5 introduced to simplify connection to FT-857. No other differences from v6
|
|
Version 6
Released: March-2012
|
Bottom label: RRC-1258MkIIs V 6 Web info page: |
New speaker amplifier
2 W on both channels
|
|
Version 5
Released: Dec-2010
|
Bottom label: RRC-1258MkIIs Web info page: |
Dual RX Support
|
|
Version 3,4
Released:
|
Bottom label: RRC-1258MkII Web info page: |
First mass produced version
|
 |
Version 1
Released: |
See picture
Web info page: |
(1) Of course the functioality will be limited to the functionality of simplest unit. For example if one of the units do not support Dual-RX audio, the combined system will not support Dual-RX audio.
* only valid from firmware v 2.57