2023-07: one of the sides broke near center, rebuying.
2021-07: wire half broke near connector, only works in some positions. The funny thing is: only voices seem to be blocked out! Rebuying.
2021-06: a small bottom piece of the left earpiece broke. Wire seems find, that is like a little extension to protect wire. Let's see for how long.
2020-20: wires at one of ears broke, not sure how.
Look they looked exactly like: "Skullcandy Smokin' Buds 2 In-Ear Audio Earbud Headphones with In-Line Microphone - Black".
Re-buying that one 10 pounds:
Tech specs:
Connection Type: 3.5mm AUX CableImpedence: 32 ohmsDriver Diameter: 9mmSound Pressure Level: 95 dB (1mW/500Hz)Frequency Response: 20kHz - 20HzHeadphone Type: In-Ear
In degrees Celsius:
- 25+
- 18-25
- "dhb Aeron Short Sleeve Jersey"
- XGC Men's Cycling Shorts
- 2020-04 Giro Rumble VR Off Road Shoe
- 15-18:
- "dhb Aeron Short Sleeve Jersey"
- "dhb Lightweight Mesh Long Sleeve Base Layer"
- XGC Men's Cycling Shorts
- 2020-04 Giro Rumble VR Off Road Shoe
- 10-15:
- dhb Classic Thermal Bib Tights 10 and under. TODO this is a bit too warm for the upper range, need something more intermediate
- "dhb Lightweight Mesh Long Sleeve Base Layer"
- Castelli Perfetto RoS Long Sleeve - Cycling jersey. TODO this is a bit too warm for the upper range, need something more intermediate
- "Karrimor X Lite Run Black Headband"
- "Nike academy hyperwarm gloves"
- "Nevica Skuff". A bit too hot on upper range, but easy to take off.
- 0-10:
- dhb Merino Long Sleeve Base Layer
- Castelli Perfetto RoS Long Sleeve - Cycling jersey
- dhb Classic Thermal Bib Tights 10 and under
- dhb Dorica MTB Shoe (2020-12)
- "Karrimor X Lite Run Black Headband". Head a bit cold on lower range.
- "dhb Neoprene Nylon Overshoes". Feet a bit cold on lower range.
- "Extremities XDRY gloves". Hands a bit cold on lower range.
- "Nevica Skuff"
This is how electronic circuits are normally prototyped!
Once you validate them like this, the next step is usually to move on to printed circuit boards for more reliable production setups.
Breadboards are a thing of beauty and wonder.
Point-to-point constructions on woden boards
. Source. Predecessors to breadboards from where the name came. A thing of beauty, so vintage. You could actually write stuff on those with a pencil!Breadboards - Trash or Treasure? by Keysight (2020)
Source. 
How to build it: math.stackexchange.com/questions/3137319/how-in-general-does-one-construct-a-cycle-graph-for-a-group/3162746#3162746 good answer with ASCII art. You basically just pick each element, and repeatedly apply it, and remove any path that has a longer version.
Immediately gives the generating set of a group by looking at elements adjacent to the origin, and more generally the order of each element.
TODO uniqueness: can two different groups have the same cycle graph? It does not seem to tell us how every element interact with every other element, only with itself. This is in contrast with the Cayley graph, which more accurately describes group structure (but does not give the order of elements as directly), so feels like it won't be unique.
Stable isotope.
where:
- : matrix in the old basis
- : matrix in the new basis
- : change of basis matrix
Subtle is the Lord by Abraham Pais (1982) page 85:so it is quite cool to see that organic chemistry is one of the things that pushed atomic theory forward. Because when you start to observe that isomers has different characteristics, despite identical proportions of atoms, this is really hard to explain without talking about the relative positions of the atoms within molecules!
However, it became increasingly difficult in chemical circles to deny the reality of molecules after 1874, the year in which Jacobus Henricus van't Hoff and Joseph Achille Le Bel independently explained the isomerism of certain organic substances in terms of stereochemical properties of carbon compounds.
This notation is designed to be relatively easy to write. This is achieved by not drawing ultra complex ASCII art boxes of every component. It would be slightly more readable if we did that, but prioritizing the writer here.
Two wires are only joined if but the following are:
+ is given. E.g. the following two wires are not joined: |
--|--
| |
--+--
|Simple symmetric components:
-,+and|: wireAC: AC source. Parameters:e.g.:If only one side is given, the other is assumed to be at a groundAC_1Hz_2VG.C: capacitorG: ground. Often used together withDC, e.g.:means applying a voltage of 10 V across a 10 Ohm resistor, which would lead to a current of 1 ADC_10---R_10---GL: inductorMICROPHONE. As a multi-letter symmetric component, you can connect the two wires anywhere, e.g.or:---MICROPHONE---| MICROPHONE |SPEAKERR: resistorSQUID: SQUID deviceX: Josephson junction
Asymmetric components have multiple letters indicating different ports. The capital letter indicates the device, and lower case letters the ports. The wires then go into the ports:
D: diodeSample usage in a circuit:a: anode (where electrons can come in from)c: cathode
Can also be used vertically like aany other circuit:--aDc--We can also change the port order, the device is still the same due to capital| a D c |D:--cDa-- | Dac-- | Dca-- | --caDDCDC source. Ports:E.g. a 10 V source with a 10 Ohm resistor would be:p: positiven: negative
If only one side is given, the other is assumed to be at a the ground+---pDC_10_n---+ | | +----R_10------+G. We can also omitpandmin that case and assume thatpis the one used, e.g. the above would be equivalent to:If the voltage is not given, it is assumed to be a variable voltage power supply.DC_10---R_10---GLED: same as diodeI: electric current source. Ports:P: potentiometer source. Ports:1: one of the sides2: the middle3: the other side
T: transistor. The ports aresgTd:Sample usage in a circuit:s: sourceg: gated: gate
All the following are also equivalent:---+ | --sgTd--| g --sTd-- | --Tsgd-- |- ports can also be separated by double underscores from the component names to increase readability. Single underscores can also be used to increase readability of longer multi-word component names e.g.:which is the same as:
RPI_PICO_W__1gp0__3gnd | | R_2k | | | +-aLEDc-+represents a circuit linking port 1 of a Raspberry Pi Pico W, which is GPIO pin 0, through a resistor and an LED, back to pin 3 of the board, which is ground.RPI_PICO_W 1gp0 3gnd | | R_2k | | | +-aLEDc-+
Numbers characterizing components are put just next to each component with an underscore. When there is only one parameter, standard units are assumed, e.g.:means:Micro is denoted as
+-----+
| |
C_1p R_2k
| |
+-----+u. There are unlisted articles, also show them or only show them.