I did a topic on this on the old forum, the text only may be available via the link below, it is on my computer but I also have the original on the same machine.
http://www.gscalecentral.net/tm?m=2003&high=voltage < Link To http://www.gscalecentral....=2003&high=voltage
I suggest three alternatives.
One replace the LGB board with a chip with analogue capability and screw terminals such as a Massoth eMotion XL or an ESU Lokpilot XL for around £55. This will give you all the lighting and power outputs you need and also, of course, digital operation when you visit DCC layouts.
Two, build three voltage regulators, one for bi-directional lights etc. and one each for forward and reverse functions as per the diagram below. You could omit D1 C2 and C3 in all three circuits as they are a bit OTT for this application.
Three, replace the bulbs with higher voltage (around 18V to 24V) ones or leds with suitable resistors wired to the track via diodes for direction.
Option three may result in the lights being dim at normal operating speed but would allow automatic directional led lighting by using red/white diodes. If you wanted to do this using the voltage regulator you would need two separate leds for each light, I suggest a conventional clear white one with a red surface mount version fixed behind it.
Whatever you choose I strongly advise checking any remaining wiring for faults as this a fault in it may possibly have caused the original problem.
