"TRAIN DETECTION VOLTAGE DROP?"

[nambo]

Hi, do the following train detectors (if used for a DC run HO scale layout) create any voltage drop-

-OptoCoupled
-Twin-T transistor
-Twin-T I.C.
-Transformer train detector.

If any of the above train detectors do create any voltage drop, would anyone know if the voltage drop would slow down the trains running over the detector track?

And would a Transformer train detector work for detecting HO scale trains run on a normal block control DC layout?-"any plans for this detector to??"

[cwclark]

all of them in the "Twin - T " family do...they use diodes and diodes cause voltage drops which will slow the train down thru a block...the only one i've found that doesn't cause a voltage drop is the DALLEE Train detection circuit....Dallee uses a current detector that doesn't actually connect to the circuit itself to detect trains in a block because the wire makes a loop thru the detector that sets off the detector thru a separate power source when it senses a voltage drop thru an insulated wire...that's why i use them..they are really easy to wire and....no voltage drops...here's a pick of a set-up using dallee TDC's..the detectors are in the upper right corner of the board...do you see the reddish orange things on the circuit boards..the wire just goes from the block toggle switch to the detector by making two passes with loops in the wire around the current detector and then to one rail in the track...click to enlarge ...chuck