• 2 Posts
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Joined 1 year ago
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Cake day: March 31st, 2025

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  • there might be something in there, any short question about SPPS devolves into gratuitous nonsense mashing together standard peptide coupling conditions, sometimes from three different approaches or more (publicly available from reagent suppliers, there are many variants so most of info repeats) even when it’s not the right tool to use. The more obscure reagent or use case, the faster it devolves into word salad, even if there’s clear analogy to more common one. Which, to be fair, is to be expected

    another one, How to initiate formation of Grignard reagent from alkyl bromide
    • this is a reaction very strongly inhibited by water. product (grignard reagent) sweeps all water, which makes reaction faster, so if you dump all bromide in at once there will be nothing happening, then you get thermal runaway instantly and possibly magnesium fire. so the way to go is to make small amount at first, then go up from there slowly. generally you don’t need to try very hard as long as everything is dry; procedures given are cribbed from syntheses using aryl bromides, which might require some prodding, old ones of which used small amount of alkyl bromide as initiator which here is useless advice. Curiously this didn’t hit guardrails, as this led to many accidents when done by clueless people including meth lab fires

    Before i hit usage limit, two different chatbots happily devised schemes for ESD protection for zener diode (it’ll be fine without, zener diodes are used for this)





  • It’s up for you to decide. On U/VHF you can talk to other people directly (locally) like on HF. But you can also do things that HF can’t provide, or provides with limitations, like talk through repeater (uncommon on HF), or to ISS, or through satellites (HF bounces from ionosphere) or do longer distance communications from mountaintops, or do image transmission or packet radio (HF has less bandwidth). On receive only you can also download NOAA weather satellite images, or whatever else data are emitted by them. You can make your own repeater from two baofengs. HF gets affected by space weather, U/VHF is not, and we’re entering solar minimum. 6m will take you far further than 2m but it’s usually bundled with HF radios

    On higher end there’s also moonbounce, but it’s not in the budget category

    e: there’s 50 things you can do with SDR only (many on U/VHF) https://blinry.org/50-things-with-sdr/