How to Write a Good Protocol

Motivation Writing Good Protocols Examples Tips for LaTeX Summary
How to Write a Good Protocol
Mathias Magdowski
Chair for Electromagnetic Compatibility
Institute for Medical Engineering
Otto von Guericke University, Magdeburg
License: cba CC BY-SA 3.0 (Attribution + ShareAlike)
Writing Good Protocols 1

Structure
Motivation
How to Write a Good Protocol?
Content
Style
Good and Bad Examples
Tips for LaTeX
Diagrams with pgfplots
Wiring Schematics with circuitikz
Summary

Motivation
Protocols:
laboratory internships
research projects/degree theses
measurements/experiments in the working life

Motivation
Protocols:
laboratory internships
research projects/degree theses
measurements/experiments in the working life
Purpose and principal components:
experimental procedure
observations
evaluation & discussion of results

Content
Protocol structure:
1. cover page
2. theoretical fundamentals
3. preparation of the experiment
4. experimental procedure and evaluation
number and content of each experimental part
test circuit
measurement data in tabular form
evaluation and discussion of results
5. literature / references
6. declaration of authorship
7. appendix (scanned original measurement data)

Cover Page
Content:
university, institute, chair, course
topic, number and date of the experiment
group and adviser
colloquium, date of submit

Cover Page
Content:
university, institute, chair, course
topic, number and date of the experiment
group and adviser
colloquium, date of submit
Important:
stick to the template
ﬁll in completely

Theoretical Fundamentals
Good:
fundamentals and equations for the procedure and
evaluation
give sources
length: 1 to 3 pages

Theoretical Fundamentals
Good:
fundamentals and equations for the procedure and
evaluation
give sources
length: 1 to 3 pages
Bad:
too general and too broad
too detailed derivation of formulas
copy from the instructions

Preparation of the Experiment
Tips:
timely
don’t be too creative
check the script or exercise notes
If things get complicated, you are usually on the wrong
way!

Experimental Procedure and Evaluation
Important:
follow the given subcategorization
introductory and transitioning sentences
give units correctly
number equations, ﬁgures and tables
remain accurate

Experimental Procedure and Evaluation
Important:
follow the given subcategorization
introductory and transitioning sentences
give units correctly
number equations, ﬁgures and tables
remain accurate
Discussion:
anomalies, difﬁculties or peculiarities
accuracy, error sources, improvement opportunities

Literature / References
Example:
[1] Martha Davis, Kaaron J. Davis and Marion M. Dunagan.
Scientiﬁc papers and presentations.
Academic Press, London, Great Britain, 2012.
http://dx.doi.org/10.1016/B978-0-12-384727-0.00001-X.
[2] Lutz Hering and Heike Hering.
How to Write Technical Reports: Understandable Structure,
Good Design, Convincing Presentation.
Springer-Verlag, Berlin, Heidelberg, 2010.
http://dx.doi.org/10.1007/978-3-540-69929-3.

Example:
http://dx.doi.org/10.1016/B978-0-12-384727-0.00001-X.
http://dx.doi.org/10.1007/978-3-540-69929-3.
see https://www.ieee.org/documents/ieeecitationref.pdf

Example:
http://dx.doi.org/10.1016/B978-0-12-384727-0.00001-X.
http://dx.doi.org/10.1007/978-3-540-69929-3.
see https://www.ieee.org/documents/ieeecitationref.pdf
see http://www.emv.ovgu.de/

Appendix
Content:
scanned original measurement data
other handwritten notes

Appendix
Content:
scanned original measurement data
other handwritten notes
Important:
resolution, contrast, brightness of the scan
visible signature of the adviser
no “scrap sheets”

Style
protocol ˆ= small degree thesis

Style
protocol ˆ= small degree thesis
see Guidance on the Preparation of Degree
Theses

Diagrams
0 2 4 6 8 10 12 14 16 18 20
−200
0
200
Time, t (in ms)
Voltage,u(t)(inV)
sine wave-form
cosine wave-form
Figure 1: Harmonic time course of a voltage with a frequency of 50 Hz
and an effective value of 230 V

Tables
Table 1: Measurement data for a charging process
Time, t in s 0 1 2 3
Voltage, U in V 0.00 1.26 1.73 1.90

Diagrams and Tables
Table captions (above) and ﬁgure captions (below):
self-contained and understandable
better too long than too short

Diagrams and Tables
Reference in the text:
“see Table 1” or “. . . is shown in Figure 1”
not “the following ﬁgure”

Diagrams and Tables
Reference in the text:
“see Table 1” or “. . . is shown in Figure 1”
not “the following ﬁgure”
Really bad:
JPEG compressed raster graphics for diagrams

Further Hints
introduce abbreviations and variables when used the ﬁrst
time

Further Hints
time
insert cross references (e. g. “as shown in Section 3, . . . ”
or “on Page 4”)

Further Hints
time
or “on Page 4”)
non-breaking spaces after Figure, Table, Page, Section,
Equation, . . . and between numbers and units

Further Hints
time
or “on Page 4”)
hyphen vs. dash

Further Hints
time
or “on Page 4”)
hyphen vs. dash
no references as footnotes

Further Hints
time
or “on Page 4”)
hyphen vs. dash
no references as footnotes
see https:
//en.wikipedia.org/wiki/Electronic_symbol

Units
see the SI brochure of the BIPM
Formatting:
units upright (also abbreviations, function and operators in
formulas), e. g.:
Umax = 1 V instead of Umax = 1 V
sin(x) instead of sin(x)
ex
instead of ex
df
dx instead of df
dx
(thin) space between number and unit
consistent format (e. g. km h−1 vs. km
h )
U[V] is wrong, instead U/V
2.998 × 108 instead of 2,998 E+008

LiveQuiz at www.lehrevaluation.ovgu.de
Which word processing software are you currently using
for writing laboratory protocols?
1. Microsoft Word
2. OpenOffice or
LibreOffice
3. LATEX (also on
ShareLaTeX or
Overleaf)
4. Scientific WorkPlace
5. LyX
6. something different
Code: lvlkp

Software
WYSIWYG:
Microsoft Word
Apache OpenOfﬁce

Software
WYSIWYG:
Microsoft Word
Apache OpenOfﬁce
LaTeX:
MikTeX
TeXLive

Software
WYSIWYG:
Microsoft Word
Apache OpenOfﬁce
LaTeX:
MikTeX
TeXLive
WYSIWYM:
LyX
Scientiﬁc WorkPlace
BaKoMa TeX

Software
from https://xkcd.com/1301/

Software for Figures
Dia:
Download: https://wiki.gnome.org/Apps/Dia/
from Wikimedia Commons -
https://commons.wikimedia.org/wiki/File:Dia-gtk.png#/media/File:Dia-gtk.png

Ipe:
Download: http://ipe.otfried.org/
from Wikimedia Commons -
https://commons.wikimedia.org/wiki/File:Ipe6pre30.png#/media/File:Ipe6pre30.png

Inkscape:
Download: https://inkscape.org/
from Wikimedia Commons - https://commons.wikimedia.org/wiki/File:
Inkscape_0.48.1.png#/media/File:Inkscape_0.48.1.png

XnView:
Download: http://www.xnview.com/de/xnview/

Hints for LATEX Users
Useful packages:
hyperref: activation of PDF commands
amsmath: typesetting of mathematical equations
siunitx: formatting of units
pgfplots: creation of diagrams
circuitikz: creation of wiring schematics
tikz: “TikZ ist kein Zeichenprogramm”
csquotes: consistent quotation marks
cite: better citations in the running text

Hints for LATEX Users
Useful editors:
Texmaker
TeXstudio
TeXworks
TeXShop (for Mac)
TeXnicCenter (for Windows) with SumatraPDF

Example 1:
M04 Brückenschaltungen
1. Grundlage des Versuchs
Brückenschaltung:
Eine Brückenschaltung ist eine elektrische Schaltung, die aus der Paralleschaltung zweier
Spannungsteiler zu einer gemeinsamen Spannungsquelle oder Stromsquelle. Die
Brückenspannung ( Ausgangsspannung ) ergibt sich aus der Differenz der Beiden Teilspannungen
der Spannungsteiler.
Abgleichbrücken:
Die Abgleichbrücke dient der Bestimmung der Bauelementegrößen. Unter Verwendung der
Abgleichbedingungen werden die gesuchte Parameter berchnet. Durch Verändern eines oder
mehrerer der vier Widerstände bzw. Impandanzen in Spannungsteilern wird ein Nullabgleich der
Brpckenspannung erreicht. Das bedeutet, dass die Brückenspannung bzw. der Brückenstrom Null
wird. Bei dem Wechselstrom muss auch die Phase ebenfalls Null sein.
Ausschlagbrücke:
Wenn eine Brückenschaltung außerhalb des Nullabgleichs betrieben wird und die
Brückenspannung bzw. der zugehörige Brückenstrom als interessierende Größe gemessen,
spricht man von einer Ausschlagbrücke.
Phasendrehbrücke:
Die Brückenspannung besitzt im diesen Fall im Vergleich zur Eingangspannung eine
Phasenverschiebung. Es ist abhängig von Variation eines oder mehrer Brückenelemente.
2. Versuchsvorbereitung

Example 1:
M04 Brückenschaltungen
1 Grundlagen des Versuchs
Brückenschaltung: Eine Brückenschaltung ist eine elektrische Schaltung, die aus der Parallel-
schaltung zweier Spannungsteiler zu einer gemeinsamen Spannungsquelle oder Stromquelle. Die
Brückenspannung (Ausgangsspannung) ergibt sich aus der Diﬀerenz der Beiden Teilspannungen
der Spannungsteiler.
Abgleichbrücken: Die Abgleichbrücke dient der Bestimmung der Bauelementegrößen. Unter Ver-
wendung der Abgleichbedingungen werden die gesuchte Parameter berechnet. Durch Verändern ei-
nes oder mehrerer der vier Widerstände bzw. Impedanzen in Spannungsteilern wird ein Nullabgleich
der Brückenspannung erreicht. Das bedeutet, dass die Brückenspannung bzw. der Brückenstrom
Null wird. Bei dem Wechselstrom muss auch die Phase ebenfalls Null sein.
Ausschlagbrücke: Wenn eine Brückenschaltung außerhalb des Nullabgleichs betrieben wird und
die Brückenspannung bzw. der zugehörige Brückenstrom als interessierende Größe gemessen, spricht
man von einer Ausschlagbrücke.
Phasendrehbrücke: Die Brückenspannung besitzt im diesen Fall im Vergleich zur Eingangspan-
nung eine Phasenverschiebung. Es ist abhängig von Variation eines oder mehrere Brückenelemente.
2 Versuchsvorbereitung

Example 2:
Inhaltsverzeichnis
1.Theoretische Grundlagen zum Versuch
1.1 Versuchsziel S.4
1.2 Digitalspeicheroszilloskop S.4
2.Vorbereitungsleistung zum Versuch
2.1 Begriffserklärungen S.5
2.2 Zusammenhang zwischen der Augenblicksleistung und
Wirkleistung S.6
3.Versuchsdurchführung
3.1 Durchführen einfacher Messungen
3.1.1 Versuch 3.1.1 S.8
3.1.2 Versuch 3.1.2 S.9
3.1.3 Versuch 3.1.3 S.11
3.1.4 Versuch 3.1.4 S.13Writing Good Protocols 31

Example 2:
Inhaltsverzeichnis
1 Theoretische Grundlagen zum Versuch 1
1.1 Versuchsziel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2 Digitalspeicheroszilloskop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
2 Vorbereitungsleistung zum Versuch 2
2.1 Begriﬀserklärungen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.2 Zusammenhang zwischen Augenblicksleistung und Wirkleistung . . . . . . . . . 3
3 Versuchsdurchführung 4
3.1 Durchführen einfacher Messungen . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3.1.1 Versuch: Wirkung verschiedener Bedienelemente . . . . . . . . . . . . . 4
3.1.2 Versuch: Messung der Periodendauer mittels des Cursors . . . . . . . . 5
3.1.3 Versuch: Oszillographieren eines Halbsinussignals und Wirkung der Ka-
nalkopplung . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Example 3:
520 1950.30700167834 980 3036.18957673975
540 2370.79699684715 1000 3074.07165349513
Table 1: Quality factor for different frequencies from the measurement of E-field strength.
The resulting graph is shown below:
Q
f (MHz)
Figure 1: Quality factor with response to frequency.
We observe that the Quality factor increases until a frequency (around 850 MHz) and the decreases as is isWriting Good Protocols 33

Example 3:
100 200 300 400 500 600 700 800 900 1000
0
2000
4000
6000
Frequency, f (in MHz)
Qualityfactor,Q
Figure 2: Measured quality factor as a function of the frequency

Example 4:
Abblidung 7: Vergleichdiagramm 3.3.2
Die beiden Kurven überlagern sich.
3.4 Stromgespeiste Ausschlagbrücke
Iq = 12mA RL = 430Ω
Abblidung 8: Messschaltung 3.4.1
∆R2 in Ω ∆R1 in Ω IRr in mA gegenläufig
0 1000 0,02
100 900 0,37Writing Good Protocols 35

Example 4:
Iq
R2 = 1000 Ω
R = 820 Ω
R1 = 1000 Ω
I1
R = 820 Ω
I2
RL = 430 Ω
IBr

Example 5:
List of Figures
2.1 Figure showing the experimental measurement results for f = 45.87 MHz . 4
2.4 Graphs showing the variation of quality factor with respect to frequencies
for diﬀerent cases. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Example 5:
List of Figures
2.1 Experimental results for the resonance curve at f = 45.87 MHz . . 4
2.4 Variation of the quality factor with respect to the frequency for
diﬀerent cases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Example 6:
Graﬁk 4:Oszillogramm zum Versuch 3.1.2 Messen der Periodendauer mit
dem Cursormodus
Durch das Messen der Periodendauer mit dem Cursor wurde eine Periodendauer
von T=1992 Hz ermittelt. Dies ist eine Abweichung von 8Hz im Vergleich zu
dem Ergebnis aus Versuch 3.1.1. Diese Abweichung resultiert aus der ungenauen
Figure 3: Oscillogram to measure the periodic time using markers

Example 6:
Improvement opportunities:
hide the menu
optimum setting of the horizontal and vertical resolution
hide unnecessary curves and parameters
never save as JPG, better as PNG
insert in reasonable size

Example 7:
Thoretical 𝑓𝑟
[MHz]
𝑓𝑟 [MHz] ∆𝑓 [kHz] Q
31.25 28.8 250 115
45.09 49.59 580 85.5
53.40 51.37 424 121.16
1.2. From the E-Field Strength in the Chamber
At higher frequencies the discrete resonance lines cannot be separated from
each other anymore. The quality factor must then be calculated from the energy
that is stored inside the chamber, and the energy per cycle period that is converted
due to losses. This gives a relation between the ﬁeld strength in the cavity, the
input or dissipated power and the quality factor. In this part of the experiment the
quality factor shall be determined in that manner.
 derivation of the relation between the quality factor, the ﬁeld strength and
the input power:
𝑄 =
𝜔[𝑠−1
] ∙ 𝑈[𝑉]
𝑃𝑑[𝑊]
With
𝜔 is the angular frequency, 𝜔 = 2 𝜋𝑓
U– the energy stored by RC ,
𝑃𝑑 – the average dissipated power in a period.
𝑈 = 𝑊 ∙ 𝑉, (2)
With
W- energy density,
V – volume of chamber.
𝑊 = |𝐸|2
∙ 𝜀, (3)
With

Example 7:
1.2 From the E-Field Strength in the Chamber
At higher frequencies, the discrete resonance lines cannot be separated from each
other anymore. The quality factor must then be calculated from the energy that
is stored inside the chamber, and the energy per cycle period that is converted
input or dissipated power and the quality factor. In this part of the experiment,
the quality factor shall be determined in that manner.
To derive a relation between the quality factor, the ﬁeld strength and the input
power, one can give the quality factor a
Q =
ω · U
Pd
, (1.1)
where ω = 2πf is the angular frequency, U is the energy stored in the reverberation
chamber and Pd is the average dissipated power in one period.
The stored energy in the reverberation chamber can by given by
U = W · V , (1.2)
where W is the energy density and V is the volume of the chamber.

Example 7:
1.2 From the E-Field Strength in the Chamber
At higher frequencies, the discrete resonance lines cannot be separated from each
other anymore. The quality factor must then be calculated from the energy that
is stored inside the chamber, and the energy per cycle period that is converted
input or dissipated power and the quality factor. In this part of the experiment,
the quality factor shall be determined in that manner.
To derive a relation between the quality factor, the ﬁeld strength and the input
power, one can give the quality factor a
Q =
ω · U
Pd
, (1.1)
where:
ω = 2πf is the angular frequency,
U is the energy stored in the reverberation chamber and
Pd is the average dissipated power in one period.

Example 7:
The stored energy in the reverberation chamber can by given by
U = W · V , (1.2)
where:
W is the energy density and
V is the volume of the chamber.

Why are you not using LATEX (or what was your biggest
anxiety before using it)?
1. not aware of it
2. too complicated/
like programming
3. too time-consuming/
shallow learning curve
4. only used in academics,
not used in the industry
5. no advantages over
Microsoft
Word/OpenOfﬁce Code: lvsqp

begin{tikzpicture}
begin{axis}
addplot+[
domain=0:20,
samples=101,
] {sin(deg(x*2*pi/20))*sqrt(2)*230};
end{axis}
end{tikzpicture}

0 5 10 15 20
−200
0
200

Axis Labels
begin{tikzpicture}
begin{axis}[
xlabel={Time, $t$ (in si{millisecond})},
ylabel={Voltage, $u(t)$ (in si{volt})},
]
addplot+[
domain=0:20,
samples=101,
] {sin(deg(x*2*pi/20))*sqrt(2)*230};
end{axis}
end{tikzpicture}

Axis Labels
0 5 10 15 20
−200
0
200
Time, t (in ms)
Voltage,u(t)(inV)

Axis Limits
begin{tikzpicture}
begin{axis}[
xmin=0,xmax=20,
ymin=-350,ymax=350,
]
addplot+[
domain=0:20,
samples=101,
] {sin(deg(x*2*pi/20))*sqrt(2)*230};
end{axis}
end{tikzpicture}

Axis Limits
0 5 10 15 20
−200
0
200
Time, t (in ms)
Voltage,u(t)(inV)

Scaling
begin{tikzpicture}
begin{axis}[
xmin=0,xmax=20,ymin=-350,ymax=350,
width=0.8textwidth,
height=0.5textwidth,
]
addplot+[
domain=0:20,
samples=101,
] {sin(deg(x*2*pi/20))*sqrt(2)*230};
end{axis}
end{tikzpicture}Writing Good Protocols 53

Scaling
0 2 4 6 8 10 12 14 16 18 20
−200
0
200
Time, t (in ms)
Voltage,u(t)(inV)

Second Curve and Legend
begin{tikzpicture}
begin{axis}[
xmin=0,xmax=20,ymin=-350,ymax=350,
width=0.8textwidth,height=0.5textwidth,]
addplot+[domain=0:20,samples=101]
{sin(deg(x*2*pi/20))*sqrt(2)*230};
addlegendentry{sine wave-form};
addplot+[domain=0:20,samples=101]
{cos(deg(x*2*pi/20))*sqrt(2)*230};
addlegendentry{cosine wave-form};
end{axis}
end{tikzpicture}Writing Good Protocols 55

Second Curve and Legend
0 2 4 6 8 10 12 14 16 18 20
−200
0
200
Time, t (in ms)
Voltage,u(t)(inV)
sine wave-form
cosine wave-form

Further Options of the pgfplots Package
Data from:
formulas
direct speciﬁcation of data points
text ﬁles

Further Options of the pgfplots Package
Data from:
formulas
direct speciﬁcation of data points
text ﬁles
Types of diagrams:
line plots (linear, smooth, constant)
bar plots (horizontal, vertical)
comb plots and quiver plots
polar coordinates, ternary axes, Smith chart
3D: line, mesh, surface, contour

begin{tikzpicture}
% outer loop
draw (0,0) to[I] (0,4)
to[short] (4,4)
to[vR] (4,2)
to[R] (4,0)
to[short] (0,0);
end{tikzpicture}

Adding Inner Branches
begin{tikzpicture}
% outer loop
draw (0,0) to[I] (0,4)
to[short] (4,4)
to[vR] (4,2)
to[R] (4,0)
to[short] (0,0);
% inner branches
(2,4) to[vR] (2,2)
to[R] (2,0)
(2,2) to[R] (4,2);
end{tikzpicture}

Adding Inner Branches

Labels
begin{tikzpicture}
% outer loop
draw (0,0) to[I] (0,4)
to[short] (4,4)
to[vR, l=${R_2=SI{1000}{ohm}}$] (4,2)
to[R, l=${R=SI{820}{ohm}}$] (4,0)
to[short] (0,0)
% inner branches
(2,4) to[vR, l_=${R_1=SI{1000}{ohm}}$] (2,2)
to[R, l_=${R=SI{820}{ohm}}$] (2,0)
(2,2) to[R, l=${R_{ind{L}}=SI{430}{ohm}}$] (4,2);
end{tikzpicture}

Labels
R2 = 1000 Ω
R = 820 Ω
R1 = 1000 Ω
R = 820 Ω
RL = 430 Ω

Scaling
begin{tikzpicture}[xscale=1.6,yscale=1.2]
% outer loop
draw (0,0) to[I] (0,4)
to[short] (4,4)
to[vR, l=${R_2=SI{1000}{ohm}}$] (4,2)
to[R, l=${R=SI{820}{ohm}}$] (4,0)
to[short] (0,0)
% inner branches
(2,4) to[vR, l_=${R_1=SI{1000}{ohm}}$] (2,2)
to[R, l_=${R=SI{820}{ohm}}$] (2,0)
(2,2) to[R, l=${R_{ind{L}}=SI{430}{ohm}}$] (4,2);
end{tikzpicture}

Scaling
R2 = 1000 Ω
R = 820 Ω
R1 = 1000 Ω
R = 820 Ω
RL = 430 Ω

Currents, Soldering Points
begin{tikzpicture}[xscale=1.6,yscale=1.2]
% outer loop
draw (0,0) to[I, i=$I_{ind{q}}$] (0,4)
to[short] (4,4)
to[vR, l=${R_2=SI{1000}{ohm}}$] (4,2)
to[R, l=${R=SI{820}{ohm}}$] (4,0)
to[short] (0,0)
% inner branches
(2,4) to[vR, l_=${R_1=SI{1000}{ohm}}$,
i>^=$I_1$, *-] (2,2)
to[R, l_=${R=SI{820}{ohm}}$, i=$I_2$, -*] (2,0)
(2,2) to[R, l=${R_{ind{L}}=SI{430}{ohm}}$,
i>_=$I_{ind{Br}}$, *-*] (4,2);
end{tikzpicture}

Currents, Soldering Points
Iq
R2 = 1000 Ω
R = 820 Ω
R1 = 1000 Ω
I1
R = 820 Ω
I2
RL = 430 Ω
IBr

Further Options of the circuitikz Package
Components:
Monopoles: ground, antennas, . . .
Bipoles: basic elements, sources, instruments, . . .
Tripoles: transistors, controlled sources, switches, . . .
Double bipoles: transformers, couplers, . . .

Further Options of the circuitikz Package
Components:
Monopoles: ground, antennas, . . .
Bipoles: basic elements, sources, instruments, . . .
Tripoles: transistors, controlled sources, switches, . . .
Double bipoles: transformers, couplers, . . .
Display and labels:
current and voltage arrows
node labels
European or American style
( vs. )

What LATEX-related topics would you like to see in future
workshops?
1. typesetting formulas
2. typesetting tables
3. citing sources and listing
references
4. drawing schematics (e.g. of
a measurement setup)
5. creating presentation slides
6. Don’t bother me with
LaTeX!
Code: lvwst

Summary
The adviser should see that you tried
hard and took care!

Summary
large protocol ˆ= degree thesis

Thanks for your attention!
Are there questions?

Examples
Diagram in pgfplots:
https://goo.gl/7SMpif
Circuit schematic in CircuiTikZ:
https://goo.gl/XJG6eG

How to Write a Good Protocol

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