Difference between revisions of "Undergraduate Radio Lab"

Latest revision as of 13:53, 23 March 2023

This course consists of four laboratory experiments that concentrate on radio instrumentation and laboratory techniques. We will build receiving, observing, and data analysis systems for two telescopes: a single-dish 21-cm line system, and a 10.7-GHz interferometer. We will use these telescopes for astronomical observing projects including structure of the Milky Way galaxy, precise position measurement of several radio sources, and measurement of the radio brightness distributions of the sun and moon with high angular resolution. There is a heavy emphasis on digital data acquisition, software development in the Python language, and high-quality written reports.

Class Programmatics[edit]

Class Code Repository: http://github.com/AaronParsons/ugradio
Source code for SNAP spectrometer/correlator: https://github.com/darbymccauley/snap_spec
Syllabus
Zoom Room: 358 760 9756
Bcourses: 1523462
Discord: https://discord.gg/ge4EVK2n
Sign-up for group telescope/observation time: https://calendar.app.google/vp6w1HRSxeAUKgEk7
Check out an RPi: https://forms.gle/4S4x3vxpJ36yXc1d6
Class Hours:
- Tuesday/Thursday 1:30-3:30pm
Office Hours:
- Aaron Parsons (aparsons at berkeley): or by appointment, in standard Zoom Room: 358 760 9756
  - Thursday 3:30pm - 5:00pm
  - Friday 11:00am - 1:00pm
- Darby McCauley (darbymccauley at berkeley):
  - Monday 10:30am - 1:30pm
  - Tuesday 11:00am - 12:30pm
  - Wednesday 11:00am - 12:30pm
  - Friday 2:00pm - 5:00pm
  - Appointment, in person or Zoom (email me)
- Dirk Wright (dirkw at berkeley):
Lab Groups:
- Group 1
- Group 2
- Group 3
- Group 4
- Group 5

Experiments[edit]

Getting Set Up[edit]

Getting Started in the Undergraduate Radio Lab
- Setting Up Your Raspberry Pi
- Connecting to the Lab Computers Remotely

General Skills Used Through-Out Course[edit]

Navigating Linux/Unix-like Operating Systems
- Unix Primer
- Unix Text Editors
Programming in Python
- Python Installation and Basic Programming
- Introduction to Python and Plotting
Software Engineering
Report Writing
- LaTeX

Topics by Date[edit]

Lab 1 (Exploring Digital Sampling, Fourier Transforms, and both DSB and SSB Mixers), Due Feb 6, 11:59p[edit]

Lab 1, Week 1 (Jan 17): Sampling and Power Spectra[edit]

Resources and Handouts
- Nyquist Sampling
- Fourier Transform
- Technical Skills

Demos and Tutorials
- Introduction to Python and Plotting
- Aliasing Demo (on datahub.berkeley.edu)
In class:
- Astrobaki, Syllabus, Office Hours
- Getting accounts (premade by Bill Boyd, change password with passwd command)
- Lab access (see Getting Started in the Undergraduate Radio Lab)
- Class philosophy and workflow
- Nyquist Sampling and aliasing
- Fourier Transform
- ADC Quantization
- Lab Hardware
  - PicoScope 2206a
  - Raspberry Pi + NESDR Smart
- Data Challenge
  - Secret Message
- Lecture 1 Zoom recording (2021 is here)
- Lecture 2 Zoom recording (2021 is here)

Lab 1, Week 2 (Jan 24): DSB and SSB Mixers[edit]

Theory and Background:
Demos and Tutorials
- Convolutions and Correlations
- In the Mind: Introduction to the Fourier Transform
- Mommy Fortuna's Midnight Carnival of Python Oddities
- Data Representations, with handout on Data Types and Organizational Structures
- Data Challenge
  - Secret Message 2
In class:
- Lecture 3 Zoom recording (2021 is here)
- Lecture 4: Show and Tell
- Lecture: Introduction to DSB and SSB Mixers
- Show and Tell (10m per group)

Lab 1, Week 3 (Feb 1): More Mixers, and Lab Reports[edit]

Theory and Background
- LaTeX
- Introduction to Python and Plotting, second pass
- LaTex Template Template you may use for your lab report
  - Overleaf version of the lab template
In Class:
- Lecture: One more pass on Convolution Theorem, Heterodyne Mixers, and DFTs
- Lecture 5
- Lecture 6
- Show and Tell
- Writing Lab Reports
Lab 1 Due Feb 6, 11:59p

Lab 2 (Astronomy with the 21cm Line; Some Microwave Electronics), due Feb 27, 11:59p[edit]

Lab 2, Week 1 (Feb 7): 21cm Line and Waveguides[edit]

Theory and Background:
Demos and Tutorials
- Python Tutorial Part 3: Functions, Modules, and Objects
- Matrix Math with Numpy
- Doppler Corrections, ugradio.doppler
In class:
- Introduction to Horn and Receiver
- Time
- Coordinates
- Lecture 7
- Lecture 8

Lab 2, Week 2 (Feb 14): Collect and Analyze Data[edit]

Theory and Background
Demos and Tutorials
- Central Limit Theorem and Averaging
In Class:
- Show and Tell
- Waveguides, Transmission Lines, and Rope
- Fitting Gaussians and Polynomials, ugradio.gauss
- Lecture 9
- Lecture 10

Lab 2, Week 3 (Feb 21): Write Lab Report[edit]

Theory and Background
- Least-Squares and Chi-Square for the Budding Aficionado: Art and Practice
In Class:
- Chi-Square Jupyter Notebook
- Show and Tell
- Least Squares Part 2
- Lecture 11
Lab 2 Due Feb 27, 11:59p

Lab 3 (Radio Interferometry at X Band), due Apr 3, 11:59pm[edit]

Lab 3 Week 1 (Mar 1): Interferometer[edit]

Theory and Background
- Coordinates
- Basic Interferometry
In Class:
- Tour of Rooftop Interferometer
- Exercise Ball Coordinates
- Interferometry with Strings
- Lecture 12
- Lecture 13

Lab 3 Week 2 (Mar 8): Collect and Analyze Data[edit]

Theory and Background
- Measurement Equation
- Telescope Field of View/Resolution
In Class:
- Show and Tell
- Controlling the Telescope
- Tracking the Sun
- Scheduling Observations
Lecture Links
- Lecture 14
- Lecture 15

Lab 3 Week 3 (Mar 15): Collect and Analyze Data[edit]

Theory and Background
- Basic Interferometry II
- Least Squares
In Class:
- Show and Tell
- Linear Least-Squares in Python
- Minimizing Chi-Square]
- Noise in Observations
Lecture Links
- Lecture 16
- Lecture 17

No class (Mar 23, 26)[edit]

Lab 3 Week 4 (Mar 29): Write Lab Report[edit]

Theory and Background
- - Correlators
  - Units of radiation
In Class:
- Show and Tell
- Photon bucket demo
Lecture Links
- Lecture 18
- Lecture 19
Lab 3 Due Apr 6, 1:30p

Lab 4 (Mapping the HI Line: the Galaxy and Supershells), due May 3, 1:30p[edit]

Useful Links[edit]

Link to Observing Calendar

Leuschner WebCam

Lab 4 Week 1 (Apr 4): Leuschner Dish[edit]

Theory and Background
In Class:
- Trip to Leuschner: Class will go later than usual
- drive mechanism (how the dish moves)
- feed (notice probes) and cables
- IF setup (one channel for OH, one for HI)
- interacting with a CASPER spectrometer
- pointing control
- spatial sampling with dish
Lecture Links
- Lecture 20
- Lab 4 Lecture 2 (Thursday 4/9/20)

Lab 4 Week 2 (Apr 11): Collect and Analyze Data[edit]

Theory and Background
In Class:
- Show and Tell
- spatial sampling with a dish
- interpolation
- projection
Lecture Links
- Lab 4 Lecture 3 (Tuesday 4/14; access v7*1$5k7)
- Lab 4 Lecture 4 (Thursday 4/16; access G7*##+1O)

Lab 4 Week 3 (Apr 18): Collect and Analyze Data[edit]

Theory and Background
In Class:
- Show and Tell
- close-out plan
- computing doppler width for a line of sight (assuming circular motion)
- calibrating spectra
- converting spectra to hydrogen
Lecture Links
- Lab 4 Lecture 5 (Tuesday 4/21; access 7f!o&=J9)
- Lab 4 Lecture 6 (Thursday 4/23): share day; no recording

Lab 4 Week 4 (Apr 25): Write Lab Report[edit]

Theory and Background
- Calibrating the Intensity and Shape of Spectral Lines (Carl Heiles)
In Class:
- Show and Tell
- displaying information in image form
- Lab 4 Due May 3, 1:30p
Lecture Links
- Lab 4 Lecture 7 (Tuesday 4/28; access 3h=j11*@ )
- Lab 4 Lecture 8 (Thursday 4/30; access 5V$.3i8$ )

@@ Line 3: / Line 3: @@
 === Class Programmatics ===
 * Class Code Repository: [http://github.com/AaronParsons/ugradio http://github.com/AaronParsons/ugradio]
-* [https://github.com/AaronParsons/ugradio/raw/master/schedule/syllabus_2022_spring.docx Syllabus]
+* Source code for SNAP spectrometer/correlator: [https://github.com/darbymccauley/snap_spec https://github.com/darbymccauley/snap_spec]
+* [https://github.com/AaronParsons/ugradio/raw/main/schedule/syllabus_2023_spring.docx Syllabus]
 * [https://berkeley.zoom.us/j/3587609756 Zoom Room: 358 760 9756]
-* Bcourses: [https://bcourses.berkeley.edu/courses/1512067 1512067]
+* Bcourses: [https://bcourses.berkeley.edu/courses/1523462 1523462]
-* Discord: https://discord.gg/vdmcyZcAbS
+* Discord: https://discord.gg/ge4EVK2n
+* Sign-up for group telescope/observation time: https://calendar.app.google/vp6w1HRSxeAUKgEk7
+* Check out an RPi: https://forms.gle/4S4x3vxpJ36yXc1d6
 * Class Hours:
 ** Tuesday/Thursday 1:30-3:30pm
 * Office Hours:
-** Aaron Parsons (aparsons at berkeley): TBD, or by appointment, in standard [https://berkeley.zoom.us/j/3587609756 Zoom Room: 358 760 9756]
+** Aaron Parsons (aparsons at berkeley): or by appointment, in standard [https://berkeley.zoom.us/j/3587609756 Zoom Room: 358 760 9756]
-** Christian Bye (chbye at berkeley): TBD or by appointment (Through Discord Office Hours Channel)
+*** Thursday 3:30pm - 5:00pm
-** Mine Gokcen (minegokcen at berkeley):
+*** Friday 11:00am - 1:00pm
-** Frank Latora (fjlatora at berkeley):
+** Darby McCauley (darbymccauley at berkeley):
+*** Monday 10:30am - 1:30pm
+*** Tuesday 11:00am - 12:30pm
+*** Wednesday 11:00am - 12:30pm
+*** Friday 2:00pm - 5:00pm
+*** Appointment, in person or Zoom (email me)
+** Dirk Wright (dirkw at berkeley):
 * Lab Groups:
 ** Group 1
@@ Line 22: / Line 31: @@
 === Experiments ===
-* Lab 1: [https://github.com/AaronParsons/ugradio/blob/master/lab_mixers/allmixers.pdf Exploring Digital Sampling, Fourier Transforms, and both DSB and SSB Mixers]
+* Lab 1: [https://github.com/AaronParsons/ugradio/blob/main/lab_mixers/allmixers.pdf Exploring Digital Sampling, Fourier Transforms, and both DSB and SSB Mixers]
-* Lab 2: [https://github.com/AaronParsons/ugradio/blob/master/lab_bighorn/bighorn.pdf Astronomy with the 21cm Line; Some Microwave Electronics]
+* Lab 2: [https://github.com/AaronParsons/ugradio/blob/main/lab_bighorn/bighorn.pdf Astronomy with the 21cm Line; Some Microwave Electronics]
-* Lab 3: [https://github.com/AaronParsons/ugradio/blob/master/lab_interf/interf.pdf Radio Interferometry at X Band]
+* Lab 3: [https://github.com/AaronParsons/ugradio/blob/main/lab_interf/interf.pdf Radio Interferometry at X Band]
-* Lab 4: [https://github.com/AaronParsons/ugradio/blob/master/lab_dish/HI1.pdf Mapping the HI Line: the Galaxy and Supershells]
+* Lab 4: [https://github.com/AaronParsons/ugradio/blob/main/lab_dish/HI1.pdf Mapping the HI Line: the Galaxy and Supershells]
 ===Getting Set Up===
@@ Line 39: / Line 48: @@
 * Programming in Python
 ** [[Python Installation and Basic Programming]]
-** [https://github.com/AaronParsons/ugradio/blob/master/jupyter_tutorials/lab1/python_intro.ipynb Introduction to Python and Plotting]
+** [https://github.com/AaronParsons/ugradio/blob/main/jupyter_tutorials/lab1/python_intro.ipynb Introduction to Python and Plotting]
 * Software Engineering
 ** [[Revision Control]]
@@ Line 49: / Line 58: @@
 == Topics by Date ==
-=== Lab 1 ([https://github.com/AaronParsons/ugradio/blob/master/lab_mixers/allmixers.pdf Exploring Digital Sampling, Fourier Transforms, and both DSB and SSB Mixers]), Due Feb 8, 1:30p ===
+=== Lab 1 ([https://github.com/AaronParsons/ugradio/blob/main/lab_mixers/allmixers.pdf Exploring Digital Sampling, Fourier Transforms, and both DSB and SSB Mixers]), Due Feb 6, 11:59p ===
-==== Lab 1, Week 1 (Jan 18): Sampling and Power Spectra ====
+==== Lab 1, Week 1 (Jan 17): Sampling and Power Spectra ====
 * Resources and Handouts
 ** [[Nyquist Sampling]]
@@ Line 62: / Line 71: @@
 * Demos and Tutorials
-** [https://github.com/AaronParsons/ugradio/blob/master/jupyter_tutorials/lab1/python_intro.ipynb Introduction to Python and Plotting]
+** [https://github.com/AaronParsons/ugradio/blob/main/jupyter_tutorials/lab1/python_intro.ipynb Introduction to Python and Plotting]
-** [https://github.com/AaronParsons/ugradio/blob/master/jupyter_tutorials/lab1/Nyquist%20Sampling%20and%20Aliasing.ipynb Aliasing Demo]
+** [https://github.com/AaronParsons/ugradio/blob/main/jupyter_tutorials/lab1/Nyquist%20Sampling%20and%20Aliasing.ipynb Aliasing Demo] (on [http://datahub.berkeley.edu/user-redirect/interact?account=AaronParsons&repo=ugradio&branch=main&path=jupyter_tutorials/Nyquist%20Samplling%20and%20Aliasing.ipynb datahub.berkeley.edu])
 * In class:
 ** Astrobaki, Syllabus, Office Hours
-** Getting accounts (premade by Bill Boyd, change password)
+** Getting accounts (premade by Bill Boyd, change password with <tt>passwd</tt> command)
 ** Lab access (see [[Getting Started in the Undergraduate Radio Lab]])
 ** Class philosophy and workflow
 ** [[Nyquist Sampling]] and aliasing
 ** [[Fourier Transform]]
+** ADC Quantization
 ** Lab Hardware
 *** PicoScope 2206a
+*** Raspberry Pi + [[NESDR Smart]]
 ** Data Challenge
-*** [https://github.com/AaronParsons/ugradio/blob/master/lab_mixers/secret_message.npz Secret Message]
+*** [https://github.com/AaronParsons/ugradio/blob/main/lab_mixers/secret_message.npz Secret Message]
-** [https://youtu.be/Yb4K8t6SG4k Lecture 1 Zoom Recording]
+** [https://youtu.be/uH-dQnq7ZD4 Lecture 1 Zoom recording] (2021 is [https://youtu.be/Yb4K8t6SG4k here])
-** [https://youtu.be/oJplegmHeAI Lecture 2 Zoom Recording]
+** [https://youtu.be/LtEzUnp_E9E Lecture 2 Zoom recording] (2021 is [https://youtu.be/oJplegmHeAI here])
-==== Lab 1, Week 2 (Jan 26): DSB and SSB Mixers ====
+==== Lab 1, Week 2 (Jan 24): DSB and SSB Mixers ====
 * Theory and Background:
 ** [[Heterodyne Mixers]]
 ** [[Convolution Theorem]]
 ** [[Fast Fourier Transform]]
-** [https://github.com/AaronParsons/ugradio/blob/master/dft_intro/fourierc.pdf Spectral Analysis with Discrete Fourier Transforms]
+** [https://github.com/AaronParsons/ugradio/blob/main/dft_intro/fourierc.pdf Spectral Analysis with Discrete Fourier Transforms]
 * Demos and Tutorials
-** [https://github.com/AaronParsons/ugradio/blob/master/jupyter_tutorials/lab1/Convolutions%20and%20Correlations.ipynb Convolutions and Correlations ]
+** [https://github.com/AaronParsons/ugradio/blob/main/jupyter_tutorials/lab1/Convolutions%20and%20Correlations.ipynb Convolutions and Correlations ]
-** [https://github.com/AaronParsons/ugradio/blob/master/jupyter_tutorials/lab1/Sec%204.%20In%20the%20mind.ipynb In the Mind: Introduction to the Fourier Transform ]
+** [https://github.com/AaronParsons/ugradio/blob/main/jupyter_tutorials/lab1/Sec%204.%20In%20the%20mind.ipynb In the Mind: Introduction to the Fourier Transform ]
-** [https://github.com/AaronParsons/ugradio/blob/master/jupyter_tutorials/lab1/datatype_demo.ipynb Mommy Fortuna's Midnight Carnival of Python Oddities]
+** [https://github.com/AaronParsons/ugradio/blob/main/jupyter_tutorials/lab1/datatype_demo.ipynb Mommy Fortuna's Midnight Carnival of Python Oddities]
-** [[Data Representations]], with handout on [https://github.com/AaronParsons/ugradio/blob/master/pythonprimer/datatypes.pdf Data Types and Organizational Structures]
+** [[Data Representations]], with handout on [https://github.com/AaronParsons/ugradio/blob/main/pythonprimer/datatypes.pdf Data Types and Organizational Structures]
 ** Data Challenge
-*** [https://github.com/AaronParsons/ugradio/blob/master/lab_mixers/mixed_message.npz Secret Message 2]
+*** [https://github.com/AaronParsons/ugradio/blob/main/lab_mixers/mixed_message.npz Secret Message 2]
 * In class:
-** [https://youtu.be/Ut_jTUoqcd8 Lecture 3: Discrete Fourier Transforms and the Convolution Theorem]
+** [https://youtu.be/dsCZ_F2HEVY Lecture 3 Zoom recording] (2021 is [https://youtu.be/Ut_jTUoqcd8 here])
 ** [https://youtu.be/ZxAWNiisn3Y Lecture 4: Show and Tell]
 ** Lecture: Introduction to DSB and SSB Mixers
@@ Line 100: / Line 111: @@
 * Theory and Background
 ** [[LaTeX]]
-** [https://github.com/AaronParsons/ugradio/blob/master/jupyter_tutorials/lab1/python_intro.ipynb Introduction to Python and Plotting], second pass
+** [https://github.com/AaronParsons/ugradio/blob/main/jupyter_tutorials/lab1/python_intro.ipynb Introduction to Python and Plotting], second pass
-** [https://github.com/AaronParsons/ugradio/tree/master/latex_template/lab1 LaTex Template] Template you may use for your lab report
+** [https://github.com/AaronParsons/ugradio/tree/main/latex_template/lab1 LaTex Template] Template you may use for your lab report
 *** [https://www.overleaf.com/read/hvrwkmfkvkhg Overleaf version of the lab template]
 * In Class:
-** Lecture: One more pass on [[Convolution Theorem]], [[Heterodyne Mixers]], and [https://github.com/AaronParsons/ugradio/blob/master/dft_intro/fourierc.pdf DFTs]
+** Lecture: One more pass on [[Convolution Theorem]], [[Heterodyne Mixers]], and [https://github.com/AaronParsons/ugradio/blob/main/dft_intro/fourierc.pdf DFTs]
 ** [https://youtu.be/igZPQQ-6ieo Lecture 5]
 ** [https://youtu.be/53CZj1CCEm0 Lecture 6]
 ** Show and Tell
 ** Writing Lab Reports
-* Lab 1 Due Feb 8, 1:30p
+* Lab 1 Due Feb 6, 11:59p
 ---------
-=== Lab 2 ([https://github.com/AaronParsons/ugradio/blob/master/lab_bighorn/bighorn.pdf Astronomy with the 21cm Line; Some Microwave Electronics]), due Mar 1, 1:30p ===
+=== Lab 2 ([https://github.com/AaronParsons/ugradio/blob/main/lab_bighorn/bighorn.pdf Astronomy with the 21cm Line; Some Microwave Electronics]), due Feb 27, 11:59p ===
-==== Lab 2, Week 1 (Feb 8): 21cm Line and Waveguides ====
+==== Lab 2, Week 1 (Feb 7): 21cm Line and Waveguides ====
 * Theory and Background:
-** [https://github.com/AaronParsons/ugradio/blob/master/lab_bighorn/cal_intensity.pdf Calibrating the Intensity and Shape of Spectral Lines]
+** [https://github.com/AaronParsons/ugradio/blob/main/lab_bighorn/cal_intensity.pdf Calibrating the Intensity and Shape of Spectral Lines]
 ** [[Specific Intensity]]
 ** [[21cm Transition]]
@@ Line 131: / Line 142: @@
 ** [https://youtu.be/htF9zWPzeLQ Lecture 8]
-==== Lab 2, Week 2 (Feb 15): Collect and Analyze Data ====
+==== Lab 2, Week 2 (Feb 14): Collect and Analyze Data ====
 * Theory and Background
 ** [[Impedance]]
@@ Line 137: / Line 148: @@
 ** [http://ugastro.berkeley.edu/radio/2017/handout_links/RWvD.pdf Fields and Waves in Communication Electronics (Ramo, Whinney, and Van Duzer)]
 ** [[Central Limit Theorem]] and [[Random Walks]]
-** [https://github.com/AaronParsons/ugradio/blob/master/least_squares/lsfit_lite.pdf Least Squares Lite for the Budding Aficionado: Art and Practice]
+** [https://github.com/AaronParsons/ugradio/blob/main/least_squares/lsfit_lite.pdf Least Squares Lite for the Budding Aficionado: Art and Practice]
 * Demos and Tutorials
-** [https://github.com/AaronParsons/ugradio/blob/master/jupyter_tutorials/lab2/Central%20Limit%20Theorem%20and%20Averaging.ipynb Central Limit Theorem and Averaging]
+** [https://github.com/AaronParsons/ugradio/blob/main/jupyter_tutorials/lab2/Central%20Limit%20Theorem%20and%20Averaging.ipynb Central Limit Theorem and Averaging]
 * In Class:
 ** Show and Tell
@@ Line 147: / Line 158: @@
 ** [https://youtu.be/xre1hQiZKCM Lecture 10]
-==== Lab 2, Week 3 (Feb 22): Write Lab Report ====
+==== Lab 2, Week 3 (Feb 21): Write Lab Report ====
 * Theory and Background
-** [https://github.com/AaronParsons/ugradio/blob/master/least_squares/lsfit_2008.pdf Least-Squares and Chi-Square for the Budding Aficionado: Art and Practice]
+** [https://github.com/AaronParsons/ugradio/blob/main/least_squares/lsfit_2008.pdf Least-Squares and Chi-Square for the Budding Aficionado: Art and Practice]
 * In Class:
-** [https://github.com/AaronParsons/ugradio/blob/master/jupyter_tutorials/lab2/chisq_intro.ipynb Chi-Square Jupyter Notebook]
+** [https://github.com/AaronParsons/ugradio/blob/main/jupyter_tutorials/lab2/chisq_intro.ipynb Chi-Square Jupyter Notebook]
 ** Show and Tell
 ** Least Squares Part 2
 ** [https://youtu.be/M92l0k45Gjw Lecture 11]
-* Lab 2 Due Mar 1, 1:30p
+* Lab 2 Due Feb 27, 11:59p
 ---------
-=== Lab 3 ([https://github.com/AaronParsons/ugradio/blob/master/lab_interf/interf.pdf Radio Interferometry at X Band]), due Apr 5, 1:00p ===
+=== Lab 3 ([https://github.com/AaronParsons/ugradio/blob/main/lab_interf/interf.pdf Radio Interferometry at X Band]), due Apr 3, 11:59pm ===
 ==== Lab 3 Week 1 (Mar 1): Interferometer ====
@@ Line 215: / Line 226: @@
 ---------
-=== Lab 4 ([https://github.com/AaronParsons/ugradio/blob/master/lab_dish/HI1.pdf Mapping the HI Line: the Galaxy and Supershells]), due May 3, 1:30p ===
+=== Lab 4 ([https://github.com/AaronParsons/ugradio/blob/main/lab_dish/HI1.pdf Mapping the HI Line: the Galaxy and Supershells]), due May 3, 1:30p ===
 ==== Useful Links ====
@@ Line 222: / Line 233: @@
 [http://leuschner.berkeley.edu:8080 Leuschner WebCam]
-==== Lab 4 Week 1 (Apr 5): Leuschner Dish ====
+==== Lab 4 Week 1 (Apr 4): Leuschner Dish ====
 * Theory and Background
 ** [[Specific Intensity]]
@@ Line 239: / Line 250: @@
 ** [https://berkeley.zoom.us/rec/share/yYtJDpzz52pOc5GR42PxBbA_QorFT6a81CAfr6IKyRre8X_2LRtd9NPzNNLXeBCw Lab 4 Lecture 2 (Thursday 4/9/20)]
-==== Lab 4 Week 2 (Apr 12): Collect and Analyze Data ====
+==== Lab 4 Week 2 (Apr 11): Collect and Analyze Data ====
 * Theory and Background
 ** [[21cm Transition]]
@@ Line 253: / Line 264: @@
 ** [https://berkeley.zoom.us/rec/share/wsAsELX3yThOTJXExEjjWaI4Mdq7eaa8hicf__AEzEkISCgjfujdIe8CV-yXP8VP Lab 4 Lecture 4 (Thursday 4/16; access G7*##+1O)]
-==== Lab 4 Week 3 (Apr 19): Collect and Analyze Data ====
+==== Lab 4 Week 3 (Apr 18): Collect and Analyze Data ====
 * Theory and Background
 ** [[Emission Line Observing]]
@@ Line 269: / Line 280: @@
 ** Lab 4 Lecture 6 (Thursday 4/23): share day; no recording
-==== Lab 4 Week 4 (Apr 26): Write Lab Report ====
+==== Lab 4 Week 4 (Apr 25): Write Lab Report ====
 * Theory and Background
-** [https://github.com/AaronParsons/ugradio/blob/master/lab_bighorn/cal_intensity.pdf Calibrating the Intensity and Shape of Spectral Lines (Carl Heiles)]
+** [https://github.com/AaronParsons/ugradio/blob/main/lab_bighorn/cal_intensity.pdf Calibrating the Intensity and Shape of Spectral Lines (Carl Heiles)]
 * In Class:
 ** Show and Tell