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@@ -8,6 +8,10 @@ MkDocs). But the few that do, are here.
 
 Projects below are sorted reverse chronologically (most recent first).
 
+## [Reflow Workshop: A Journal](reflow-workshop)
+
+I'm working on it!
+
 ## [bash workshop](bash-workshop)
 
 ![Photo of workshop](img/bash-workshop/workshop.jpg)
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+# Reflow Workshop: A Journal
+
+Status: updating
+
+## 2023-03-15, Wednesday
+
+Today I took a group interview for assistants of a new hackerspace. Five
+students were present, in a room with Mr. Xiao, the manager.
+
+My prior work experience bought me some credibility, and I shared with
+Xiao my frustration not being able to properly do electronic engineering
+for lack of resources.
+
+We then took a walk in the empty hackerspace. The proper name is actually
+Tang Junyuan Student Innovation and Entrepreneurship Center, but I prefer
+hackerspace. 
+
+![A two-story hackerspace. Empty save for workbenches, chairs and
+cabinets.](img/reflow-workshop/empty_tjy.jpg)
+
+▲ This is only half of the hackerspace.
+
+We had a heck of a time discussing what this space is potential of.
+Four-wheelers. LaTeX and vim workshop up the stairs. And of course
+— reflow soldering.
+
+Reflow soldering is on my [list of life goals](../random/life_goals/), but
+it's in my dream since 2019. At that time I was a nobody in high school.
+All I could solder was through-holes. Kliment, my IRC friend (though we've
+met IRL once) kindly mailed me one of his works: [an electronic
+kitten](https://github.com/kliment/catws). It is 5cm×5cm.
+
+![Picture of cat on black PCB. The eyes are glowing
+blue](img/reflow-workshop/electronic_cat.jpg)
+
+▲ It purrs when you stroke it right; otherwise, it hisses.
+
+## 2023-03-16, Thursday
+
+So I revealed my plans to Kliment, who was very supportive as usual. He
+forwarded me an email listing the things I need.
+
+One crucial thing is that I have to program the <abbr
+title="microcontroller unit">MCU</abbr> before soldering, so I need
+a <abbr title="Quad-Flat No-leads with 32 pads">QFN32</abbr> test socket.
+Kliment estimated it to cost 800 RMB, but in China it seems to only be
+~200. I bought one for 180.
+
+## 2023-03-17, Friday
+
+Just ordered the two parts from LCSC with specific numbers: Murata
+PKMCS0909E4000-R1 and Meihua MHS110FRGBCT. LCSC gave me a 20 RMB coupon.
+
+After that I went to look for the MCUs (ATtiny88-MU) and found them in
+a random Taobao store that sells them at 7 RMB apiece. I think I might
+need other chips later, so I also added some ATtiny48 and ATmega328PB to
+my shopping cart. I asked customer service if they got any in stock. They
+said I could just place my order, so I did.
+
+Then I went to hunt for the PCB and stencils. Kliment forewarned me that
+factories use only one stencil per assembly line, so my use case is
+extremely rare. I will have to consult the manufacturer for a quote.
+
+## 2023-03-19, Sunday
+
+Talked to the sales rep of JDBPCB, they were confused for a good minute,
+then realized what I was asking for. They told me to just place my order.
+They claim they had seen this kind of thing before. Kliment suggests it
+might have been [Honza Mrazek](https://honzamrazek.cz/).
+
+Sent <abbr title="basically a zip file of everything the factory needs to
+produce PCBs and stencils">Gerbers</abbr> to them, along with my requests
+in the notes. They PCBs are approved.
+
+## 2023-03-20, Monday
+
+I received the piezo speaker and RGB LEDs from LCSC today.
+
+To my surprise JDB approved my stencil request, and priced it at an
+unexpectedly low 80 RMB.
+
+Later the customer service approached me to confirm once again that
+I wanted 10 copies of the same stencil. Upon hearing yes, they revealed
+that the 80 RMB was actually the price for *one* stencil, but for me they
+could do 216 RMB for 10, tax included, with the implication that I do not
+do this kind of shit to them again. They fear me.
+
+Kliment helped shave off 46 RMB off my budget. I was looking for
+a hotplate which he said will not cost more than 80 RMB. When I told him
+best I could find is 135, he said I was looking for the wrong thing; what
+I need is not a hotplate advertised for solder work, but a consumer grade
+for heating food and beakers. I changed the keyword and found one at 89.
+
+## 2023-03-21, Tuesday
+
+Cell batteries, holders, and the QFN32 socket have arrived.
+
+![QFN32 socket with lid open](img/reflow-workshop/qfn32_socket.jpg)
+
+▲ \*Kneels on floor\* \*Unlids socket\* \*Presents brand new ATtiny88-MU\*
+Will you marry me?
+
+The socket is a delicate piece of hardware. You would place the MCU in
+a 5mm×5mm slot where two adjacent pins are 0.5 mm apart, and access them
+from a <abbr title="Dual In-line Package">DIP</abbr> interface where that
+distance (also known as the lead pitch) is 2.54 mm.
+
+The microcontrollers on the other hand haven't even begun shipping yet.
+I asked them what's wrong, and their answer was: "we don't have them."
+
+…Then don't sell them?
+
+I then asked when they will be back on stock. They read my messages but
+remained silent. Chances are they will never ship, says Kliment. This is
+just a scam on a chain of fake distributors. The evening they finally gave
+in, offering a refund.
+
+At the same time I'm looking for more trustworthy vendors. Kliment
+referred me to Winsource. Although a Shenzhen company, they don't seem to
+ship to China under that brand. So I reverse engineered a bit to find that
+its Chinese trademark is 聚源鑫. Small company, not super well-known, not
+even a store on Taobao. I'll talk to them in working hours tomorrow.
+
+I am currently inside an episode of self-doubt. What if I fail to learn
+reflow myself? Even if I can barely manage, what qualification do I have
+to teach other people? Perhaps I should have picked my battles and went
+for a simple SMD hand soldering workshop instead. That's much much easier,
+and I have done this three times.