[-] fullsquare@awful.systems 2 points 16 minutes ago

only if you take notes

[-] fullsquare@awful.systems 24 points 5 hours ago

this advice is specifically about sulfuric acid. it's denser than water, so if added to it it will sink diluting itself along the way, while also heating water around and making it float to the surface. if done opposite way, water won't mix immediately because of large density difference so neutralizatio heat will be deposited on surface between these two boiling water and throwing acid around. this matters less with other acids because less heat is deposited, and in some cases acid is less dense than water. but if you stir the acid quickly, you can do it either way as long as you control temperature. this also is the case when you need to mix two different acids

tldr you can do whatever you want as long as you know what are you doing

[-] fullsquare@awful.systems 25 points 8 hours ago

chips and bare pcbs are fabbed in taiwan/sk as you could expect, but soldering and further steps happen in poland. here you have some photos from inside their tiny factory https://www.komputerswiat.pl/nauka-i-technika/w-polsce-znajduje-sie-jedyna-w-europie-fabryka-pamieci-jest-co-podziwiac/x4kce8e

[-] fullsquare@awful.systems 2 points 14 hours ago* (last edited 14 hours ago)

at least they haven't crammed ai into it (so far, i guess)

[-] fullsquare@awful.systems 1 points 16 hours ago

that must be a particular choice, because ventoy works on both

[-] fullsquare@awful.systems 6 points 17 hours ago

speaking of oracle, they recently loaded up on debt and got into deals that are all but impossible to fulfill, and in a couple of years their survival will depend on openai making profit. (not revenue) put a pin in it and come back to that in a year or three

[-] fullsquare@awful.systems 2 points 1 day ago

where i live it's a part of building code that hot water has to be hot enough that legionella doesn't survive in it. depending on the place it might be different and whether building is up to code is a separate thing entirely

[-] fullsquare@awful.systems 3 points 1 day ago

legionella dies after 2min at 60C tho

[-] fullsquare@awful.systems 1 points 1 day ago* (last edited 1 day ago)

depends on your buildings construction, if you have steel piping then it should be fine as long as you boil it. if it's chlorinated then it shouldn't even matter too hard

[-] fullsquare@awful.systems 3 points 1 day ago

openai will listen to it too

[-] fullsquare@awful.systems 21 points 2 days ago

i guess the apparent intention was so that it can be listened to, instead of read. the actual intention was to get money from the same type of person this appeals to

[-] fullsquare@awful.systems 145 points 2 days ago

i hope he's not remembered at all, like his cause (someday)

3

I'm picking up an idea left by Dick KK4OBI, that you can lower impedance of dipole by arbitrary ratio if said dipole is zigzagged or otherwise uniformly contorted in some meandering shape. Side effect is that dipole becomes shorter and needs more wire. While there's data about impedance for fundamental, there's nothing about harmonics which is something that OCFD might be expected to handle well, so guessing that the really important part is aspect ratio of meander, i've made a couple of VHF-scale models with different meander aspect ratios (and many more much smaller sections), and some of data i've been able to collect roughly matches. The thing I'm trying to figure is what aspect ratio should be to cover multiple bands while using OCFD, say 40-20-15m bands, and whether impedances at different frequencies fall at the same rate. Eventually, when i figure this out, i'll try to make a full size 40m fundamental antenna, as I think that i've figured it out in mechanical terms

However during testing it turned out that I have severe common mode current problems, as two 10mm dia split ferrite beads were evidently not enough, so what little i've been able to collect is mostly useless. When I packed up everything I've found 4 Laird 28B beads that should together give 1100 ohms of impedance or so at 100MHz which also happens to be close to lowest frequency in my setup. Is this enough? Feedline is currently about as long as shorter arm of straight dipole at 22,5:77,5 split ratio, should I change it?

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fullsquare

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