Power fade out on Two Tracks

Hi I hope someone can help out on a problem that has be baffled.
My son has a Hornby layout consisting of a the three standard radii
The outer track is connected to the middle via R8074/5 Points The middle track is connected to the Inner via R8072/3 Points Each Track has it's own R965 Controller,R602 Clip and C912 Transformer. The layout is pinned to a MDF Board overlayed with a sheet of Granite Ballast The Locomotives are Hornby R2326 060 Class J94 Hornby R2261 Flying Scotsman Bachman Class 221 5 Car Voyager with tilting action.
The Problem is locomotives fade out after different running times on the Outer and Middle Tracks
J94 Outer-20mins approx - Fade out Middle-20mins approx - Fade out Inner-OK
Flying Scotsman Outer-20mins approx - Fade out Middle-20mins approx - Fade out Inner-OK The Scotsman also seems to be jerky on the outer straights on slow running.
Voyager Outer-3/4Circuit - Fade out Middle-1 Circuit - Fade out Inner-OK
Voltmeter shows a steady decline, this returns when the locomotive is removed, attempting to restart in this period gives a short burst before it fades out again.
We first noticed the fade which I suspect has always been there when we attached a set of R406 Light Signals to the outer transformer. This gave us an obvious visual indicator of the fade out, now removed as part of troubleshoot.
I am now baffled and on the verge of a complete rebuild, before doing so if anybody has got any ideas to try out it would be very much appreciated by a clueless Dad starting to dread Christams Day.
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On 16 Nov 2004 02:44:30 -0800, snipped-for-privacy@carterbench.co.uk (Andy N) wrote:
Andy,

Swap the controller of the inner circuit with one of the other controllers and see if the fault follows the controller - i.e. do locos now fade out on the inner track and run well on whichever outer track that the (original) inner controller is now connected to. If the fault does follow controllers, then the fault is in your controllers. Otherwise, the fault would have to be in the track and wiring since you have proved out the three locos on all tracks and they would appear to be OK.
I don't know how sophisticated Hornby controllers are these days, but if they have any electronic control circuitry within them , that would be my initial guess for the source of the fault, with a component(s) that is going faulty after a period of time. If it does look like faulty controllers then you might be best taking them to someone who knows how to repair them.
i think you should hold off tearing up your track until you have checked out the controllers :-)
Jim.
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I experienced similar fade out problems with controllers I had built from scratch. I traced the problem to the fact that the voltage regulator component did not have a sufficient heatsink. As the locos ran on the layout the voltage regulator got hot and the thermal overload protection on the component cut in switching off the power to prevent damage. Clipping on the correct heatsink to the regulator cured the problem.
What is providence of the controllers - bought new, second hand, ever been repaired?
Also are all the controllers powered from a single transformer? As it would appear strange that all three controllers exhibiting the same fault.
Rich
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Try to feed the tracks at some more points first of all.
On my layout I feed every fifth track with power from
two thick leader laying under the table.
Are you running Digital or Analogue?
If you are running analogue it's very easy for you to feed
for each block and if digital, then you feed everywhere it'd
possible to solder leaders both plus and minus. Then you
will see that you have the same power on all tracks.
If you have problems when you have two or more engines
on the layout, the you need to add some more power by
installing another power supply. You can make sections on
the layout and feed from different transformers. Just make
sure that there are some insulation between the different
sections. Plastic fishplates are available in hobby shops.
Pepe

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