NMRAF 8 booster Block detector
 NMRAF8.jpg (26691 bytes) Blockdetektor.jpg (31235 bytes)
NMRAF 8 booster with data logic's connected to the    computer serial port and the power circuitry to supply the   tracks and stationary decoders. Four block detectors built on a "VERO-board". The mating to the tracks via relays and optocouplers.
Block sensor - simplified

Littfinski LDT-RS-16

This blocksensor board is project based of stripped design of commonly used solutions. 
Just a bridge rectifier and an optocoupler will do the jobb.

Littfinski feedbackmodule attached to sensors will give the oppurtunity to indicate various events on the layout. This fedbackmodule is connected to the central unit via the RS-bus (LENZ)