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crabber
20-11-2019, 10:18 PM
I have a dark motor that has died. It is only about 18 months old with hardly any use so definitely not worn up. The symptoms are no LEDs, no noise, no movement, although it does still pass the signal.
It is dry inside with everything looking OK apart from a couple of electrolytic capacitors which are possibly leaking. Does anyone know if the little PCB is obtainable or whether it is worth changing the caps. I have replaced it with a TM so no panic but it seems a shame to chuck it in the bin if it could be repaired.

Detlef
21-11-2019, 02:19 PM
I'm not familiar with the dark motor but, in general, leaking caps are a bad sign.

The problem can be just duff caps but it can also be that they are getting (or have got before they died) an overvoltage or an AC voltage due to a duff rectifier circuit. If possible try reading the working voltage on the caps labels and check to see if that sort of voltage apprears upstream.

IF IT IS A SWITCHED MODE POWER SUPPLY BE VERY, VERY CAREFUL AS THERE WILL BE SOME HIGH VOLTAGES ON THE PRIMARY SIDE.

chris-k
21-11-2019, 03:52 PM
I have the same motor for many years no problem...did have to reset it one time in the beginning,

HARDWARE RESET BY DiSEqC MOTOR
1. Cut off the power by disconnecting the coaxial cable.2. Press and hold both EAST / WEST buttons for 5 seconds.3. Reconnect the coaxial cable.4. LED1 and LED2 blink for 5 seconds.5. Then, its memory erased, the receiver rewrites the satellite table to initial one and corrects the “0”

crabber
21-11-2019, 04:57 PM
Thanks for the replies, sorry to say I don't know what a switched mode power supply is, the motor is just fed via the coax from a Vu+ Duo2 which I thought put out around 12 volts?
Thanks also for hint about a reset, I did try this when still connected to the dish, holding the buttons for a good 5 seconds but still dead after reconnection.

Detlef
21-11-2019, 06:35 PM
Ah! Forget about the warning I posted (that would have applied to a mains fed system).

If the motor only connects to the LNB cable it gets it supply from the receiver (the Vu duo) by taking a bit of whatever voltage the LNB requires. That will be 13Vdc if you are on a Vertical channel or 18Vdc for a Horizontal. A circuit near the motor will regulate that power to probably 12V and the DiSEqC signal will be decoded on the PCB to control the motor.

You may be lucky and the the fault is just that the leaking capacitors are shorting the power output of the regulator that feeds the DiSEqC decoder (the control circuit barely needs any current so would easily be compromised). As caps are cheap I would change the leaky ones and any whose tops are swollen.

Good luck.

__________________
Just for interest, switch mode power supplies rectify the mains producing a voltage over 300V DC and that gets pulsed through a very small transformer to eventually produce a regulated lower voltage. The older alternative was a monster transformer that just converted 230Vac into whatever but often 12Vac which was then rectified to produce a dc output (as in older car battery chargers).

chris-k
22-11-2019, 02:50 PM
Thanks for the replies, sorry to say I don't know what a switched mode power supply is, the motor is just fed via the coax from a Vu+ Duo2 which I thought put out around 12 volts?
Thanks also for hint about a reset, I did try this when still connected to the dish, holding the buttons for a good 5 seconds but still dead after reconnection.

why not disconnect as the hint given for exclude that issue ??
1. Cut off the power by disconnecting the coaxial cable........