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Snacks
snacks
trying to figure out wtf 6v ac means and what voltage i can actually expect at the end of a rectifier was more of a pain than i thought (well, my intuiton seems to have been right on the rectifier but everyone throws some formula for fucking average voltage around and idk when that's useful apart from powering a resistive heater or a light bultb or smth)
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@twinspin6 ok, but my dynamo just says 6v ac 
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@twinspin6 which should mean rms, esp since bicycle dynamos are for powering light bulbs where rms makes a lot of sense
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@snacks usually it's about rms though yea
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@snacks if it's not explicitly specified it probably is rms like with outlet voltage etc
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@twinspin6 idk how well my multimeter works with constantly fluctuating voltage from spining the wheel and riding a bike while reading a multimeter hooked up to wires dangling around the spokes is...
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@twinspin6 yeah, i'm pretty sure it's rms now. But not being too familiar with this stuff i just spent way too much time researching
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twinspin
twinspin6@outerheaven.club
@snacks measuring dc voltage while spinning the wheel should give you the rms voltage
that what it do
that what it do
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@twinspin6 the voltage isn't stable at all when just spinning the wheel by hand
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twinspin
twinspin6@outerheaven.club
@snacks hmm ig that makes sense
so does it assume a certain speed at which the full voltage is present
so does it assume a certain speed at which the full voltage is present
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@twinspin6 i'm not too sure actually. Apparently the voltage should be pretty stable at higher rpm but idk how they archieve that with just magnets and coils and all the measurements i can actually find are just watts
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@twinspin6 idk if i should grab a zener diode or a buck converter but i prob need smth
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@twinspin6 i'm mostly still amazed i can't just buy what i'm making as a commercial product. Found a lot of articles of people making this themselves or planning it
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@twinspin6 (i wanna make a speedometer that just uses the dynamo's ac frequency to get speed)
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twinspin
twinspin6@outerheaven.club
@snacks there's no real usecase when you can just plop a magnet on the wheel tbh
so maybe that's why it's not a product you can find
so maybe that's why it's not a product you can find
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@twinspin6 kinda like saying there's no usecase for internal cabling or a dynamo at all on a bicycle.
there is already a magnet on my wheel, it even provides enough power that i don't need a battery and the wires are neatly tucked away already
there is already a magnet on my wheel, it even provides enough power that i don't need a battery and the wires are neatly tucked away already
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twinspin
twinspin6@outerheaven.club
@snacks yeah so maybe it is a good idea but not something anyone cares about since you then need to provide some sort of display etc.
maybe something for higher price bikes
do they put dynamos in racing bicycles
maybe something for higher price bikes
do they put dynamos in racing bicycles
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@snacks as in higher cost for something people might not care about
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@twinspin6 very rarely, but commuter bikes can go for thousands of euros too
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