What’s the vibrating doohickey above left pedal?

[Nealius]

There’s this orb thing that vibrates when electrical power is applied, and I can’t find it in any real pictures or diagrams. What is it and why does it vibrate?

[SKYPORK]

Vibrate the panel to keep the gauge needles from sticking? But engine vibration may be enough? Or not? Maybe I have no idea?

On the planes I work on, something that looks like that under the panel is usually a gear or stall warning horn.

[grafspee]

I would say that this is some kind of electric motor, it starts shakes when you turn on electric power. But why it shakes so much i don't know.

Maybe its motor for vacuum pump. 

Edited September 29, 2021 by grafspee

[saburo_cz]

Motor Generator for Artificial Horizon
 

[DB 605]

Yes, transformer for the artifical horizon.

Edited September 29, 2021 by DB 605
screenshot

[Nealius]

Wish we had that in the Allied warbirds. Their artificial horizons are uselss and the suction gauges are stuck below minimum pressure even at max power. 

[grafspee]

2 hours ago, saburo_cz said:

Motor Generator for Artificial Horizon
 

Something like inverter on older planes where generator was driven by electric motor to provide different voltage/ frequency current for equipment ?

Edited September 29, 2021 by grafspee

[LeCuvier]

Yes, an Umformer is an electrical motor/generator. It would produce electrical power different from the general power supply's parameters. For example it might suüüly 3-phase current.