Stay alive on Loksound 3.5

[Chameleon]

I have a Tillig 060 loco in HOe, factory fitted with, I think a Loksound 3.5 (I’ve had it quite a while) it is a truly horrible runner and I just can’t get it to run reliably. I’ve checked all the pickups etc to no avail so it just sits in a siding emitting occasional random sounds. 
is it possible to fit a stay alive to one of these chips? I’m thinking of a Zemo  KA or similar as it’s a small loco. 

[RedgateModels]

I tried and failed. There's something odd about the circuitry that prevents the usual solder a wire to the negative end of the bridge rectifier and use the blue wire for the positive.

 

[Nigelcliffe]

Dig deep back into the internet and there is a solution.   I think its "two stay alives", one for the processor, and one for the main power supply/HBridge output.    It's not simple.  

[Hamburger]

You need 2 capacitors:
one for the main power supply (16V or 25V depending on the track voltage) and a second for the internal electronics (6V and about 1/4 of the capacity of the main capacitor).
The connection pads are different depending on the board version. Instructions can be found on the Internet and in the ESU manual for the LokPilot V3. To be on the safe side, the voltage at these points should always be checked again.

LokPilot manual