Breeser EXOS2 RA motor speed variation with voltage

[Fraunhoffer]

I noticed that many of my unguided pictures seem to have roughly the same amount of drift sub-sub.
This is probably a feature of my poor manual polar alignment and things flexing.
But it just occurred to me that the motors (which look the same as the MT-1 black box style on the Vixen LXD75?) came with a battery holder for 8 cells. Im running off a 12v 10a power supply ( I should check the precise voltage). 
Anyhow 8 alkaline batteries is not quite 12 v and a lead acid battery can give slightly more that 12v when fully charged

I don't know how the clock is generated inside the handcontroller to give the approx. 10 pulses per second and I wondered if there was the possibility that the pulse rate might vary slightly with the voltage.
It should have a regulator inside and I might be talking rubbish - anyhow I thought Id ask.
 

[michael8554]

With a very basic motor drive, speed would vary with voltage.

A better designed drive would only rely on the supply voltage to power a circuit that self regulates the speed irrespective of the supply voltage .

I don't know which you have.

Michael