Hi
 I'm using Kato unitrack "N" Guage and want to install a reverse loop, i have attached ( I hope) a white board sketch of a basic oval with a  a set of turnouts to create a reverse loop
Can someone tell me where the isolators should be for DCC  E.G 1,2,3 or 4 on the sketch.(Or somewhere else)  Also which part of the track is the reverse loop that the train must fit in, is the left hand "red" loop or the straignt "green" track between the turnouts ?
  I want to fit a reverse module so want to know which section ( ie red or green on sketch ) to connect the yellow wires on the reverse moduel to 

Thanks in advance alf

Without the diagonal section it would work just fine.
So all you need to take care of is that section. Whatever you find listed in regard to a reverse loop applies to that section and that section only.

Does that make sense to you?

 Thanks  As i understand it  3 + 4 will isolate the diagonal which is where the train must fit but what if i want to use the LH side of the loop instead where do i fit the isolators is it just 1+2

1 and 2 will break your normal circuit but not resolve the short circuit you create with only those applied.
Just think of what it look like if you remove the section between 1 and 2 all together.

Then you still have a reverse loop present.

So the section between the 2 switches is the section that is effectivily your reverse loop and must be dealt with as such.

On an automated track you must use 4 isolations on that track section to resolve it. With manual control you can use just 2 and make sure you switch polarity only if the train is in between the 2 isolators. You need to isolate both tracks on both ends for this to work.