diff --git a/docs/about.md b/docs/about.md
index 436f23f..a4d90e9 100644
--- a/docs/about.md
+++ b/docs/about.md
@@ -2,8 +2,8 @@
 O-ESD is open-hardware project for (pre-compliance) [ESD immunity testing](https://en.wikipedia.org/wiki/IEC_61000-4-2) in accordance with [IEC/EN 61000-4-2](https://webstore.iec.ch/en/publication/68954) standard. It is a stand-alone battery-powered portable device that can produce low-energy voltage pulses in the range from –15kV to 15kV. All electronic devices must be immune to a certain level of ESD, as ESD happens everyday between humans and electronic devices.
 ![Prototype](img_O-ESD_prototype_top_view.png)<br>
 <br>O-ESD is released under [CERN Open Hardware License Version 2 – Strongly Reciprocal](https://o-esd.etf.bg.ac.rs/IMG/cern_ohl_s_v2.txt).<br>
-<br>The current release is [version 1.0](https://o-esd.etf.bg.ac.rs/forgejo/dragan.olcan/O-ESD/src/branch/main/v1.0).<br>
-<br>Electrostatic discharge can irreparably damage electronic devices. Use O-ESD with caution!<br>
+The current release is [version 1.0](https://o-esd.etf.bg.ac.rs/forgejo/dragan.olcan/O-ESD/src/branch/main/v1.0).<br>
+Electrostatic discharge can irreparably damage electronic devices. Use O-ESD with caution!<br>
 
 ## Features
 * Contact discharge mode and air discharge mode. 
@@ -25,7 +25,7 @@ The O-ESD is powered up (or down) using the toggle switch located on the grip. T
 Once the O-ESD is powered-up the splash screen should appear for 1 s at the LCD. Afterwards, the main screen of the O-ESD shows up. LCD has four 20-character lines. Each line stands for one item. Items (i.e., lines) are selected by moving the selector “ > ” using up/down buttons.<br>
 If an item has a numeric value selectable by the user, the numeric value can be changed by rotating the knob. Some items have multiple choices (selections) or submenus (sub-items) available and those are accessible by pressing the knob.<br>
 ![UI](img_UI.png)<br><br>
-There are two modes of operation: 
+There are two modes of operation 
 * contact discharge and 
 * air discharge. 
 The default mode is the contact discharge. The sharp conductive tip (electrode) is used for contact discharge and should be placed in the red socket at O-ESD output. For air discharge the rounded conductive tip (electrode) is used and it should be placed in the black socket. O-ESD is intended for use with only one conductive tip (electrode) inserted at a time and with the appropriate mode of operation selected.<br>
@@ -84,8 +84,8 @@ Motherboard is a separate PCB connected to the grip (with 4-wire cable), to the
 ![Motherboard_assembly](img_motherboard_assembly.png)<br>
 All components of the motherboard except step-up transformer are available on the market. The step-up transformer must be assembled per specifications.<br>
 ![Trafo_assembly](img_trafo_assembly.png)<br>
-The transformer has the following roles:
-* to accumulate energy while the switching transistor is in the on state and release that energy to the high-voltage cascade when the switching transistor goes to the off state;
+The transformer has the following roles
+* to accumulate energy while the switching transistor is in the on state and release that energy to the high-voltage cascade when the switching transistor goes to the off state
 * to provide step-up voltage transformation from the low-voltage input to the high-voltage cascade and
 * to provide galvanic insulation between the low-voltage input and the high-voltage cascade.
 <br>Windings:<br>
diff --git a/docs/img_trafo_core_clips.png b/docs/img_trafo_core_clips.png
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