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Cake day: March 31st, 2025

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  • this is just a really extravagant heater, physics forbids antenna this small to have good radiation resistance. for your contrived below noise communications scheme, you need more bandwidth that is physically possible on hf, yet you choose antenna design that is even less wideband than regular dipole. 40m of wire is for 80m band, which is usable more often in this configuration, ignoring everything else

    As for throughput: a channel that is 9 KHz wide is supposed to transfer 9.6 kbit / s

    5500kbps in extremely favourable conditions is your peak attainable speed, bandwiths in normal radios are narrower

    A reasonable detection avoidance technique might be broadcasting from a depressed location or an urban canyon with tall ground clutter

    if you don’t want anyone to hear you

    launch your guerilla transmitter on a free flight balloon, and will have plentiful line of sight.

    with what power source? better study for and get your license, start using radio and stop embarrassing yourself



  • yes i know how spread spectrum schemes work, but this is not really practical or relevant here

    for spread spectrum things to work you need some wide bandwidth, this works great for microwaves where you can spread your 90GHz band signal so that it covers 5GHz, you can’t have a signal centered on 5MHz that is 5GHz wide; HF is relevant because while microwaves work with this microwaves are line of sight only and most people’s line of sight still terminates in their own country. if you live on a lone hill next to border good for you, but the rest would need to use HF to get out, and there’s simply not that much bandwidth available in the first place, which would make any scheme like this extremely slow if at all viable. and you can still jam it

    i don’t assume that satellite repeaters would be a viable option because satellite, or any other receiving party for that matter, would need to be aware of modulation scheme to receive it in the first place, so it only works if your international contacts are pre-arranged, and even then you need radio that has much larger bandwidth that is usually available. yapping on LSB or narrow digimodes will get you heard within continental range, but also it will get you noticed, but if you hide from your adversary you also hide from everyone else not in the know. and even then, you can still get noticed, because it’s under noise level only at some distance from you

    also some of these schemes require precise time to be known, and if you have gps jammed you’ll get extra problems from that

















  • Manufacturers, knowingly or unknowingly, use commercial-grade PG when making cough syrups to cut costs.

    i’d note that there’s zero technical reason why DEG would end up in PG. reaction of water with ethylene oxide gives you ethylene glycol, diethylene glycol and higher analogues and these are then separated by distillation. propylene glycol is made from propylene oxide instead, and it’s more expensive than ethylene oxide. diethylene glycol has little use on its own, at least compared to other glycols

    however,

    The physical properties of diethylene glycol make it an excellent counterfeit for pharmaceutical-grade glycerine (also called glycerol) or propylene glycol