These components react to light.
Reinforced by a receiver, included in all -I decoders, certain light pulses can be processed.
The vehicle shall be equipped with 1 or 2 IR FTR.
Thus, the signals can be picked up from the roadside.
Also, the XT-module needs a Phototransistors for receiving the feedback from the DC-Cars.
Only IR-FTR phototransistors of SMD - 0603 do matche the DC-Car System
. The notes refer only to these products.
In direct comparison with a LED the crystal looks bigger and black.
As the use of colored enamelled wires has been proved, the recommendation is:
'+ Phototransistor = violet (from 2013)' or copper-colored (confusion with indicator) or orange or red (confusion with +)
- Phototransistor = green (from 2013) or grey (from(2017)
'Measure of a phototransistor' With a sensitive ohmmeter in the setting 100 Kohm can get different ads, when light and no light is incident on the phototransistor.
This does not work with all gauges !!
'Check with a test circuit' ' An LED in series with a resistance of 1 kOhm is lit at 5 volts - 12 volts. The circiut is separated and the Fototransitor is clamped in between. With the corect polairity the LED glows, when light falls on the phototransistor. Without light, it goes out. If by mistake an IR-LED have been used instead of a Phototranistor, the LED is bright and constant.
Such tester is installed in the remote control with the Plus feature
. In the charging socket, a plug with 2 cable is plugged.
'Known problems with phototransistors'
Another stronger light source can "blinded" the phototransistors. Since they are already fully controlled by the moment, no signals can be processed.
DC Car will only respond to very short distance or not at all:
- The terminals + - of the phototransistors may be reversed.
- When gluing, no superglue must get on the front of the lens.
(UV glue is best suited for the installation of LED and in particular the phototransistors )
Also available in www.modellautobahnen.de/shop.