77. AllStar FOB. ZS6RVC for Clubhouse Project . August 2022.

An Allstar FOB (or USB FOB) is a modified USB sound card used in Allstar Link systems, which are part of the amateur radio VoIP network. These FOBs, often based on the CM108 sound card, are modified to interface with a radio transceiver, allowing it to function as a node in the Allstar network.

The modifications typically involve:

• Removing certain components like audio jacks and resistors.

• Soldering wires to specific pins on the CM108 chip.

• Adding connections for PTT (Push-To-Talk) and COS (Carrier Operated Switch) signals.

This setup enables the FOB to control radio transmissions and receive audio, effectively linking radios over the internet. It’s a popular DIY approach for building low-cost Allstar nodes.

Given your interest in radio communication systems, this could be an exciting project to explore! Have you looked into setting up an Allstar node yourself?