BFD follow focus motor intermittent connection issues and troubleshooting

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Ultra VestWhich vest should I choose for my body size, comfort and operator type?39

2009Follow Focus forum

17 years old. Gear and prices may have changed since.

Motor control knob may become unresponsive while the handset and start/stop functions remain operational, often caused by loose connector pins inside the cable housing that can be pushed inward.
Tapping on the motor or disconnecting and reconnecting the motor cable can temporarily restore function if connector pins are partially dislodged.
Underpowered power supplies rated below required amperage can cause motor twitching and erratic behavior, particularly noticeable when operating right-angle motor cables which have higher resistance than straight cables.
Using a battery power source eliminates motor twitching issues that occur with undersized AC power supplies.
The neckstrap mounting post on handsets can loosen and fall off during drops, but can be secured with breakaway threadlocker compound if a secondary handset will not be used with the butterfly bracket.
Crimp-style Lemo connector pins can be dislodged and pushed into the connector housing during rough handling or if the connecting cable has bent or misaligned pins.

The reported issue occurred on a BFD unit that had recently been serviced with an internal motor replacement.
Motor twitching from underpowered supply was only consistently reproducible with a right-angle motor cable, not with standard cables.
The exact mechanism for how connector pins became dislodged in the serviced motor remains unclear.
Manufacturers recommend against using permanent threadlocker on the neckstrap post because the connection must remain removable for using a butterfly bracket to attach two handsets together.