We have published beta versions of RRC-Micro(1.10.0), 1274B(2) and RRC-1258(2.91) that add support for CW using external paddles connected to the 1274 USB Dongle's AUX connector. If you would like to give it a try then you need to upgrade 1274B's and radio RRC-1258's firmware in addition to upgrade the RRC-Micro software.
Read about how to upgrade the 1274B firmware here:
http://www.remoterig.com/wp/?page_id=3370.
The keyer/CW function must also be enabled in RRC-Micro. That is done on a new tab called 'Keyer':
The side tone is locally generated in the PC and can be tested that it works by clicking the "Toggle tone" button. When sending CW there might be a 'click' sound at the beginning and the end of the tone. It's caused by how the PC starts and stops playing the 'beep' and is not possible to eliminate.
LF delay is used to cancel echo from the CW transmission in the radio.
Download RRC-Micro from here:
http://www.remoterig.com/firmwares/RRCMicro_1.10.1.zipRRC-1258 version 2.91 from here:
www.remoterig.com/firmwares/RRC1258-CRC-v2.91_2016-05-12-BETA.zipand 1274B version 2 from here:
remoterig.com/firmwares/1274B-2016-05-03-v2.zipWe hope that it works and that you find it useful!