diff --git a/README.md b/README.md
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--- a/README.md
+++ b/README.md
@@ -80,22 +80,25 @@ The processing pipeline is:
 
 
 ### Sensor Hardware
+
 I use the TTL IR read-write reader as specified on [volkszaehler.org](https://wiki.volkszaehler.org/hardware/controllers/ir-schreib-lesekopf-ttl-ausgang).
 
 ![IR Reader](doc/ir-reader_1.jpg)  
 ![IR Reader](doc/ir-reader_2.jpg)  
 
+
 #### SML Reading Problems
+
 If anybody else has problems reading valid SML:
-I had some real problems working with my power meter and the IR TTL sensor reader. The normal, intended placement using the magnet and directly placing it on the IR window did not yield any valid SML data, but only garbage. However, a periodicity could be observed. After tedious experiments I found out that I need a very specific spacial and rotary alignment of the sensor, see the images above. I had to put a specific distance between the sensor and the meter's IR window; I used magnets for that. With this I get valid SML packages. But even little translatory or rotary deviation leeds to invalid SML messages.
+I had some real problems working with my power meter and the IR TTL sensor reader. The normal, intended placement using the magnet and directly placing it on the IR window did not yield any valid SML data, but only garbage. However, a periodicity could be observed. After tedious experiments I found out that I need a very specific spacial and rotary alignment of the sensor, see the images above. I had to put a specific distance between the sensor and the meter's IR window; I used magnets for that. With this I get valid SML packages. But even little translatory or rotary deviation leeds to invalid SML messages. 
 Further experiments showed that the IR TTL sensor was faulty.
 If you experience similar problems, you should change (or repair) your sensor.
 
 
 
 ### Input
-Own power smart meter model is Iskraemeco MT631.
-For details see [Wiki page of Volkszaehler.org](https://wiki.volkszaehler.org/hardware/channels/meters/power/edl-ehz/iskraemeco_mt631):
+
+My power smart meter model is Iskraemeco MT631. For details see [Wiki page of Volkszaehler.org](https://wiki.volkszaehler.org/hardware/channels/meters/power/edl-ehz/iskraemeco_mt631):
   * "The meter has a bidirectional IR interface in the upper right corner, which can be read by means of an IR read-write head at 9600bd, 8N1. The connection cable of the read head points down."
   * "The meter outputs the data in SML without request."
 
@@ -111,6 +114,11 @@ The [SML](https://de.wikipedia.org/wiki/Smart_Message_Language) data is like (al
 726302017101635567000000
 ```
 
+The IR interface sends the SML data with a frequency of 1 signal per second.
+
+![IR blinking](./doc/energy_meter_infrared.gif)
+
+
 
 ### Processing
 
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