Any electronic engineers around?

[DodgyTech]

Have a baby video monitor that has stopped working (powers up, then powers off after a few seconds, repeat until plug is pulled). We have aonly ever used it from the mains adaptor, but have also tried using batteries to rule out the power adaptor. I have opened the case to see if I could spot any suspects, but the circuitry doesn't give anything away and there are no big capacitors that I could have looked at for leaks.

If anyone doesn't mind helping remotely, or giving up some of their time to help, that would save us a few bob in getting a new one. Already outside of manufacturer warranty.

 

[chookey]

Sounds like possibly a protection circuit is kicking in. High res photos of the board may be helpful.

 

[DodgyTech]

High res pictures attached.

I have figured out how to replicate the issue. The base unit doesn't play up until I turn on the parent unit (i.e. the receiver). So what that tells me is that the wireless (or RF) module in the base unit is killing the power when it makes a connection to the parent unit.

 

[Spectre]

High res pictures attached.

I have figured out how to replicate the issue. The base unit doesn't play up until I turn on the parent unit (i.e. the receiver). So what that tells me is that the wireless (or RF) module in the base unit is killing the power when it makes a connection to the parent unit.

It could be that the microcontroller is resetting the board via a power management IC or something like that if it can't talk to the RF module.