# FlexRadio 6400

## Shortcuts for SmartSDR (on Macintosh)

Global shortcuts

```

CMD-D    DX-Cluster

View
OPT-CMD-R  Radio Control
OPT-CMD-S  Slice details
OPT-CMD-P  PTT
OPT-CMD-P  Log new QSO


```

[![](https://storage.googleapis.com/2dz-data-dox/uploads/images/gallery/2026-01/scaled-1680-/r2Qf5qUNuB89R5xZ-image-1768640598091.png)](https://storage.googleapis.com/2dz-data-dox/uploads/images/gallery/2026-01/r2Qf5qUNuB89R5xZ-image-1768640598091.png)

Key mappings

[![](https://storage.googleapis.com/2dz-data-dox/uploads/images/gallery/2026-01/scaled-1680-/dgJAhfdwB7u8EkRA-image-1768640471254.png)](https://storage.googleapis.com/2dz-data-dox/uploads/images/gallery/2026-01/dgJAhfdwB7u8EkRA-image-1768640471254.png)

## Challenges

### Absence of sidetone on telegraph transmission

Solution:

Local: use phones/speaker attached to transceiver

Remote:

### Manually key the FlexRadio using SmartSDR

Solution:

Local: attach key/paddle to transceiver

Remote: via MIDI/Serial tool box, such as

<table border="1" id="bkmrk-software-solution-ch" style="border-collapse: collapse; width: 100%; height: 300px;"><colgroup><col style="width: 15.9708%;"></col><col style="width: 25.1535%;"></col><col style="width: 22.1629%;"></col><col style="width: 18.712%;"></col><col style="width: 18.1161%;"></col></colgroup><tbody><tr style="height: 29.8px;"><td style="height: 29.8px;">**Software**</td><td style="height: 29.8px;">**Solution Chain**</td><td style="height: 29.8px;">**Hardware**</td><td style="height: 29.8px;">**Pros**</td><td style="height: 29.8px;">**Cons**</td></tr><tr style="height: 46.6px;"><td style="height: 46.6px;">SmartSDR for Windows</td><td style="height: 46.6px;">HaliKey MIDI + NetKeyer for Windows, MacOS, and Linux</td><td style="height: 46.6px;">[HaliKey MIDI](https://electronics.halibut.com/product/halikey/)</td><td style="height: 46.6px;">  
</td><td style="height: 46.6px;">? no sidetone</td></tr><tr style="height: 46.6px;"><td style="height: 46.6px;">SmartSDR on Windows</td><td style="height: 46.6px;">HaliKey Serial: NetKeyer for Windows, MacOS, and Linux</td><td style="height: 46.6px;">[HaliKey Serial](https://electronics.halibut.com/product/halikey/)</td><td style="height: 46.6px;">  
</td><td style="height: 46.6px;">? no sidetone</td></tr><tr style="height: 29.8px;"><td style="height: 29.8px;">SmartSDR on Windows</td><td style="height: 29.8px;">CTR2 MIDI</td><td style="height: 29.8px;">[Lynovation - CTR2 Midi](https://ctr2.lynovation.com/ctr2-midi/)</td><td style="height: 29.8px;">Buzzer for sidetone on board</td><td style="height: 29.8px;">  
</td></tr><tr style="height: 57.8px;"><td style="height: 57.8px;">SmartSDR on Windows</td><td style="height: 57.8px;">CTR2 Micro </td><td style="height: 57.8px;">[Lynovation - CTR2 Micro](https://ctr2.lynovation.com/category/products/micro/)</td><td style="height: 57.8px;">Buzzer for sidetone on board</td><td style="height: 57.8px;">  
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