Ciro Santilli's hardware / Cycling clothes temperature guide Updated 2025-07-16
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In degrees Celsius:
  • 25+
    • palm tree shade and coconut water. Seriously though, if there's some shade or earlier morning/later afternoon it's OK, but if it's on an open road at midday, be careful, and stop early if you start getting slightly dizzy, it only gets worse!
  • 18-25
  • 15-18:
  • 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"
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Ciro Santilli's hardware / Dell Inspiron 15 3520 Updated 2025-07-16
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Some reviews:
  • the keyboard is kind of crap. Notably the key "a" is very hard to press!!
  • the lack of a sleep state indication LED and "I'm powering on LED" compared to Lenovo is really sad
  • it gets way too hot doing work (Monero bootstrap) with lid closed, likely brought system down
OPSEC: will run only cryptocurrency wallets and nothing else. Will connect to Internet, but never ever to a non clean USB flash drive.
The OPSEC for this machine supposes:
Bootstrap OPSEC:
It must have taken about one week running full time to sync the Monero blockchain which at the time was at about 3.1M blocks! I checked on system explorer, and CPU and internet usage was never maxed out, suggesting simply slow network. But the computer still overheated quite a bit and froze a few times.
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Ciro Santilli's hardware / DSD TECH USB to TTL Serial Converter CP2102 Updated 2025-07-26
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Bought in the late 2010s.
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Ciro Santilli's hardware / ELEGOO Upgraded Electronics Fun Kit Updated 2025-07-27
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  • Elegoo Breadboard power supply module MB‐V2:
    • Input voltage: 6.5-9v (DC) via 5.5mm x 2.1mm plug
    • Output voltage: 3.3V/5v
    • Maximum output current: 700 mA
    TODO center positive or center negative?
    Does not come with AC adapter, getting this one: www.amazon.co.uk/dp/B08ZN476FW output: DC 9V 1A Power Supply Adapter, Plug 5.5mm x 2.1mm, Center Positive,B rand: Security-01, input: AC 100-240V 50/60 Hz, Cable length: 1.8m
    Parts list from the ZIP:
  • resistors:
    • 10x each:
    • 30x 220
  • 1n4007 General Purpose Rectifier
  • 22pf 104 Ceramic Capacitor
  • 4N35 optocoupler
  • 74HC595 8-bit serial-in, serial or parallel-out shift register with output latches; 3-state
  • Active buzzer
  • Buttons
  • CDS-55 Photoresistor
  • Electrolytic Capacitor
  • Focusens MF52D 103f 3950 thermistor. Beta value 25/50 Celcius: 3950. R_25: I measured 9.61 k Ohms. The number 103 they document as:
    These descriptions are weird, but ChatGPT has the theory that the first two digits are actual values, and the last is multiplier, so which makes 10k.
    but I have no idea how that maps to 10 k Ohms.
  • PN2222 General Purpose Transistor
  • Passive buzzer
  • 3386p Bourns Precision Potentiometer - 1 103T: from 0 to 10k Ohms, measured with multimeter. According to the manual the "103" mean 10 k oms, which is consistent with our measurement. "P 103" is etched into the part.
  • LEDs:
    • White LED 10x
    • Kingbright RGB LEDs 10x red, green, yellow, blue:
      • maximum Continuous Forward Current: 30 mA for read and blue, 25 mA for green
      • 303025
      • under 20 mA
      20 mA appears to be the typical operation. So with the 2.0 V drop on 5 V power we want a resistor such that:
      (1)
      for the max 50 mA we would instead have 60 Ohms
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Ciro Santilli's hardware / House 2018-01 / Fridge Updated 2025-07-16
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Brand according to documents: SMEG.
Most similar models I an find: www.smeguk.com/products/UKC8173N1F and www.smeguk.com/products/UKC81721F, the keyword are "built-in" and "integrated", other very similar ones: www.smeguk.com/refrigerators/built-in
Looks like this: www.youtube.com/watch?v=4c_LBVnU4ec and that's how to unclog the drain.
2020-11-28: defrost. Some small Styrofoam was broken lose from top, noticed small burn or rust marks on top grid nearby.
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Ciro Santilli's hardware / House 2018-01 / Light bulbs Updated 2025-07-16
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2021-01: kitchen extractor right lamp burnt. Replaced with another Eveready.
2021-01: left back bulb burnt, put in another LE GU10 LED Bulbs
2020-11: kitchen extractor left lamp burnt again. Did I forget to report a right side burn earlier, or is there something wrong with the left one? Also can't find the second bulb that was likely bought last time, so likely the right one burnt and the other bulb was used for it. Buying www.amazon.co.uk/dp/B00LOBUDSS "4 x Eveready 20 W 12 V G4 Dimmable Halogen Capsule Light Bulbs Pack of 4" for 3.66 pounds. Worked, felt a bit more yellow than the previous one. Packet documents 2000 hours, 2800K color, 8000+ switches.
2020-08: kitchen right back had been out for a while, bought: www.amazon.co.uk/dp/B00LN0RPA4 LE GU10 LED Bulbs, Warm White 2700K, 50W Halogen Lamp Equivalent, 4W 350lm, 120° Wide Beam Angle, Recessed or Track Light Bulb, Pack of 5 (Energy Class A++), 5 for 10 pounds.
2019-11: front right kitchen lamp burnt, Sylvania GU10 50W. 50W was likely some useless "incandescent equivalent" measure. Replaced: GE LED 5W 345 lumens 2700K Warm 15k hours, which looks exactly the same.
2019-05: kitchen extractor left lamp burnt. Was: DURA G4 12V20W: www.amazon.co.uk/Halogen-Light-Bulbs-Lamps-5watt/dp/B003IVP12A Replaced: Sainsbury's halogen G4 20W12V.
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Ciro Santilli's hardware / House 2021 Updated 2025-07-16
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Fridge: Lamona LAM6800 fridge freezer.
Bedroon door glass pannel dimensions: 36cm x 59.6cm
Middle separator length: 2.5cm.
So total glass area: 36 * 2 + 2.5 x 59.6 * 2 + 2.5 = 74.5 x 121.7
Bin: TODO size.
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Ciro Santilli's hardware / KitchenAid Artisan toaster (2017) Updated 2025-07-16
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ARTISAN 2-SLOT TOASTER 5KMT2204 Onyx Black
Bought: 2017-09
Impossible to open to properly clean.
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Ciro Santilli's hardware / Lenovo ThinkPad P51 (2017) Updated 2025-07-16
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Bought: 2017 for approximately 2400 pounds to be Ciro Santilli's main personal laptop.
Specs:
Identifiers:
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Ciro Santilli's hardware / Liv Flourish 2 (2018) Updated 2025-07-16
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2022: saddle and seat post stolen near home. Burn in Hell, motherfuckers. Bought a seatpost marked SP342 MICROPOST ALLOY 3 30.4mm. Like this: web.archive.org/web/20220208115055/https://www.ebay.co.uk/itm/Lightweight-Alloy-Micropost-Bike-MTB-Seatpost-25-4mm-Seat-Pin-300m-Long-Silver-/402311713393 but 30.4mm. OK, bought the Park Tool PW-5 15mm pedal wrench tool. Wasn't expensive at all.
TODO understand other markings on receipt: "18 Flourish FS W Sil XS".
The exact specs pages is lost forever. Closest one we've got is the 2020: web.archive.org/web/20200927204537/https://www.liv-cycling.com/gb/flourish-2
Frame: size: XS. Marking near bottom bracket: F/N GY17Z1327 DK: WGI GY17Z1327 F ES:BI-2339.
Seatpost: TODO diameter. Measured in store 30.4mm after original stolen, although 2020 says 30.9. 30.4mm seemed to fit OK, and measuring with ruler gives 30.5/30.6, I don't think a 30.9 can possibly fit.
Saddle: Liv Contact Comfort Plus Saddle, color golden brown. Same as this but blown: www.liv-cycling.com/gb/contact-comfort-plus-saddle-liv Actual color:
https://raw.githubusercontent.com/cirosantilli/media/master/Liv_contact_comfort_plus_2018.jpg
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Ciro Santilli's hardware / Mechanical and electrical tools Updated 2025-07-16
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2020-01 "Heat Gun, SEEKONE Professional 2000W 50℃- 600℃ Variable Temperature Control Hot Air Gun Kit with 2 Temperature Modes 7 Accessories for D" www.amazon.com/dp/B078S5QMFG Initially for for cell phone repair, but later learnt they are also useful for heat shrink.
2019-09 "Draper Redline 68001 160 mm Heavy Duty Pliers Set with Soft Grip Handles (3-Piece)" web.archive.org/web/20190903191215/https://www.amazon.co.uk/dp/B071JL6LLL (archive)
2019-08: www.amazon.co.uk/dp/B000LFRYG2 (archive) "Silverline SP1236 Combination Spanner, 8-19 mm - 12 Pieces" 8.48 pounds. Because I needed the 15mm for bike pedal, and the price of 1 and the full set were very close.
6 10/11/12/13/14/17 mm Combination Wrench Set WRENCH SET COMBINATION Open-Ended Spanner/Ring Spanner Set www.amazon.co.uk/dp/B07BZLVGX8 (archive) But they sent one wrong, 8 instead of 11. Chrome Vanadium Steel. Markings: "DROP FORGED A". Quality feels crappy, not very smooth.
2017: Teng 621011 Double Open Ended Spanner 10x11mm www.amazon.co.uk/dp/B0001P0VP8 (archive)
2017: Magnusson AMS49 5M TAPE MEASURE 5m retractable flexible rule. www.screwfix.com/p/magnusson-ams49-5m-tape-measure/5315v (archive)
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Ciro Santilli's hardware / Motorola Moto G6 Play (2018) Updated 2025-07-16
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Circa 2020, a bowl fell on it from about 25 cm height and broke the screen. £159.99.
2023-10: unable to connect to Giffgaff. "Network unavailable". Same SIM works in other phones. So annoying. Update APN to match: www.giffgaff.com/help/articles/internet-apn-settings-guide. Went next to a tower and then got signal. So the receiver is much worse than the pixel one. Vibration appears to be broken.
Authy sync worked: 2023.
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Ciro Santilli's hardware / P51 benchmark Updated 2025-07-16
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glmark2 -b build:duration=3:model=horse
~4.8K
Monero 0.18.3.1 hashrate: 2.6 KH/s
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Ciro Santilli's hardware / P51 hardware Updated 2025-07-16
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lspci
output:
00:00.0 Host bridge: Intel Corporation Xeon E3-1200 v6/7th Gen Core Processor Host Bridge/DRAM Registers (rev 05)
00:01.0 PCI bridge: Intel Corporation 6th-10th Gen Core Processor PCIe Controller (x16) (rev 05)
00:08.0 System peripheral: Intel Corporation Xeon E3-1200 v5/v6 / E3-1500 v5 / 6th/7th/8th Gen Core Processor Gaussian Mixture Model
00:14.0 USB controller: Intel Corporation 100 Series/C230 Series Chipset Family USB 3.0 xHCI Controller (rev 31)
00:14.2 Signal processing controller: Intel Corporation 100 Series/C230 Series Chipset Family Thermal Subsystem (rev 31)
00:15.0 Signal processing controller: Intel Corporation 100 Series/C230 Series Chipset Family Serial IO I2C Controller #0 (rev 31)
00:16.0 Communication controller: Intel Corporation 100 Series/C230 Series Chipset Family MEI Controller #1 (rev 31)
00:17.0 SATA controller: Intel Corporation Q170/Q150/B150/H170/H110/Z170/CM236 Chipset SATA Controller [AHCI Mode] (rev 31)
00:1c.0 PCI bridge: Intel Corporation 100 Series/C230 Series Chipset Family PCI Express Root Port #1 (rev f1)
00:1c.2 PCI bridge: Intel Corporation 100 Series/C230 Series Chipset Family PCI Express Root Port #3 (rev f1)
00:1c.4 PCI bridge: Intel Corporation 100 Series/C230 Series Chipset Family PCI Express Root Port #5 (rev f1)
00:1d.0 PCI bridge: Intel Corporation 100 Series/C230 Series Chipset Family PCI Express Root Port #9 (rev f1)
00:1d.4 PCI bridge: Intel Corporation 100 Series/C230 Series Chipset Family PCI Express Root Port #13 (rev f1)
00:1f.0 ISA bridge: Intel Corporation CM238 Chipset LPC/eSPI Controller (rev 31)
00:1f.2 Memory controller: Intel Corporation 100 Series/C230 Series Chipset Family Power Management Controller (rev 31)
00:1f.3 Audio device: Intel Corporation CM238 HD Audio Controller (rev 31)
00:1f.4 SMBus: Intel Corporation 100 Series/C230 Series Chipset Family SMBus (rev 31)
00:1f.6 Ethernet controller: Intel Corporation Ethernet Connection (5) I219-LM (rev 31)
01:00.0 VGA compatible controller: NVIDIA Corporation GM107GLM [Quadro M1200 Mobile] (rev a2)
01:00.1 Audio device: NVIDIA Corporation GM107 High Definition Audio Controller [GeForce 940MX] (rev a1)
04:00.0 Network controller: Intel Corporation Wireless 8265 / 8275 (rev 78)
3e:00.0 Non-Volatile memory controller: Samsung Electronics Co Ltd NVMe SSD Controller SM981/PM981/PM983
3f:00.0 Unassigned class [ff00]: Realtek Semiconductor Co., Ltd. RTS525A PCI Express Card Reader (rev 01)
lspci -t
output:
-[0000:00]-+-00.0
           +-00.2
           +-01.0
           +-02.0
           +-02.1-[01]----00.0
           +-02.2-[02]----00.0
           +-02.4-[03]----00.0
           +-03.0
           +-04.0
           +-04.1-[04-63]--
           +-08.0
           +-08.1-[64]--+-00.0
           |            +-00.1
           |            +-00.2
           |            +-00.3
           |            +-00.4
           |            +-00.5
           |            \-00.6
           +-08.2-[65]--+-00.0
           |            \-00.1
           +-08.3-[66]--+-00.0
           |            +-00.3
           |            +-00.4
           |            \-00.6
           +-14.0
           +-14.3
           +-18.0
           +-18.1
           +-18.2
           +-18.3
           +-18.4
           +-18.5
           +-18.6
           \-18.7
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Group of Lie type Updated 2025-07-16
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In the classification of finite simple groups, groups of Lie type are a set of infinite families of simple lie groups. These are the other infinite families besides te cyclic groups and alternating groups.
A decent list at: en.wikipedia.org/wiki/List_of_finite_simple_groups, en.wikipedia.org/wiki/Group_of_Lie_type is just too unclear. The groups of Lie type can be subdivided into:
The first in this family discovered were a subset of the Chevalley groups by Galois: , so it might be a good first one to try and understand what it looks like.
TODO understand intuitively why they are called of Lie type. Their names , seem to correspond to the members of the classification of simple Lie groups which are also named like that.
But they are of course related to Lie groups, and as suggested at Video "Yang-Mills 1 by David Metzler (2011)" part 2, the continuity actually simplifies things.
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Ciro Santilli's hardware / Polytechnique USB flash drives Updated 2025-07-16
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~8GB, lsblk reports 7796176 * 1KB = 7983284224 bytes.
We got a handful of those from École Polytechnique at the end of studies I think.
They are shaped like bicornes, which is super cool, but also super impractical!
Markings: "AX ÉCOLE POLYTECHNIQUE PROMOTION X2009"
20.04 gnome-disks program reports it as: "SMI USB DISK".
From Ubuntu 20.04 on an ext4 formatted one:
/dev/sdb:
 Timing cached reads:   28656 MB in  1.99 seconds = 14421.31 MB/sec
SG_IO: bad/missing sense data, sb[]:  70 00 05 00 00 00 00 0a 00 00 00 00 20 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 Timing buffered disk reads:  42 MB in  3.03 seconds =  13.88 MB/sec
With Linux Unified Key Setup + ext4 the results are similar, maybe hdparam bypasses it?
/dev/sdb:
 Timing cached reads:   28326 MB in  1.99 seconds = 14251.55 MB/sec
SG_IO: bad/missing sense data, sb[]:  70 00 05 00 00 00 00 0a 00 00 00 00 20 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 Timing buffered disk reads:  38 MB in  3.11 seconds =  12.23 MB/sec
gnome-disks LUKS + ext4 benchmark with default params also gives about 14 MB/s.
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Ciro Santilli's hardware / Prestige 7.5L Stainless Stell Pressure Cooker (2020) Updated 2025-07-16
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Primarily bought to make borlotti beans!!!
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Ciro Santilli's hardware / Samsung MZVLB512HAJQ-000L7 512GB SSD Updated 2025-07-16
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PCIe TLC OPAL2.
sudo hdparm -Tt /dev/nvme0n1p5 on Ubuntu 20.04:
 Timing cached reads:   29812 MB in  1.99 seconds = 15007.00 MB/sec
 HDIO_DRIVE_CMD(identify) failed: Inappropriate ioctl for device
 Timing buffered disk reads: 6328 MB in  3.00 seconds = 2109.00 MB/sec
Nominal maximum sequential read speed: 3,000 MB/s
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Ciro Santilli's hardware / Seagate ST1000LM035-1RK1 1TB hard disk Updated 2025-07-16
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1TB.
sudo hdparm -Tt /dev/sda3 on Ubuntu 20.04:
 Timing cached reads:   29594 MB in  1.99 seconds = 14893.89 MB/sec
 Timing buffered disk reads: 386 MB in  3.01 seconds = 128.07 MB/sec
....
Nominal maximum speed: 140 MB/s
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Ciro Santilli's hardware / Skullcandy Smokin' Buds 2 Updated 2025-07-16
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Skullcandy earphones, first one circa. 2016 most likely. Used them a lot, these are good.
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.
Tech specs:
Connection Type: 3.5mm AUX Cable
Impedence: 32 ohms
Driver Diameter: 9mm
THD: <0.1% (1mW/500Hz) (0.0234)
Sound Pressure Level: 95 dB (1mW/500Hz)
Frequency Response: 20kHz - 20Hz
Headphone Type: In-Ear
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