Hi. I am hoping somebody may be able to help me out with this. I have a custom-made camera which somebody made for me some year back. Unfortunately I am unable to trace the engineer I commissioned to make it for me so I can't go back to him. There seems to be a problem with the circuit. Please see attached photo and diagram. It seemed that the sliding on/off switch was faulty as when I turn it on it no longer stays on, but goes on and off, depending on how I wiggle the switch. So my idea was to replace this switch. But when I looked at it in detail, I noticed that when I remove the ethernet cable from the ethernet port (top right corner) the switch works fine. I can tell this as there is a buzzer to tell me when the power is on or off. The ethernet port is used for a connection to a motor (not shown) on the camera. An ethernet cable is simply inserted into this port and the power is then supplied to the motor which is in a separate unit. The only thing I can think of is that there is a reset button on the circuit (I think this is the 'wire link' on the left-hand circuit diagram) which is used when I insert a new film in the camera. This button does the same as turning the unit off and on. I recall the maker of this telling me that I can use this button to reset or simply turn the unit off and on again. I just wonder if this reset button could be the cause. I'm sorry I can't be too technical about this...I'm just hoping there may be a way to solve this. Any advice is much appreciated. Many thanks, Dominic

 

Does the camera work ok without the motor attached,if so could be the motor is jammed,or switch dirty,
Short out the switch terminals with a screwdriver.

 

sthe motor uses current thats going through the switch. there is probably a low resistance fault in the switch.

 

I should clarify, this is a camera control unit rather than a camera in itself. This unit is used to control a motor which rolls film through a camera at varying speeds.
So, if it is a low resistance fault, this would simply be case of replacing the sliding switch? Would be great if it's that simple!
Maybe I should try this first.

 

Switch it on and short out the two pins adjacent to the black switch slider with a crocodile clip or screw driver.

Does it work properly?

 

There are three pins adjacent to the switch slider - so do I ignore the middle one? Thanks.

 

Short the outer two together,see if it will work better.

 

YES! When I short it out with the two outer prongs connected, it works fine! So, what is the cause, the switch?
Many thanks...

 

Yes its the switch...

 

thank you all so much for your help. This seems to be the solution to my problem