New Zealand Gold Prospecting & Metal Detecting Forums Archive

The larger cog is 160mm, the smaller cog is 70mm.
Presently I generate about 2 volts (with fast pedalling), my aim is 12 volts.

I was thinking of increasing the larger one's size and decreasing the smaller ones size.
Does anyone have any idea of how I could increase the power I'm generating?

Immediately.

Yeah, the max I think a cyclist can generate is 5 volts. and could get a smidgen more by altering the cog sizes.
Actually just found out I can get 12v, but need to reach 50km/h - might run into some stability issues :))))
Surprisingly it is too easy to peddal, video's I've seen say it becomes more difficult when a battery is connected - not sure if that makes any sense?
https://www.youtube.com/watch?v=lB4hXV2L7kU

Thanks, I'll investigate that 2 stage gearing.

My battery lasts for nearly 3 days. And I have a spare battery that I was going to leave at home. The alternative is to get that solar charger (leaving my dynamo at home) and take two batteries have one on recharge while I'm detecting - possibly seal it in a ziplock bag to guard against rain.

https://www.youtube.com/watch?v=ai-HNhtTMDg
This guy seems to be doing okay.

Ah, ahahahaha. Now I notice he is driving the rear wheel (~50cm diametre) which in turn drives the tiny dynamo cog (2 stage gearing I gather.

Well looks as if I'll need a ~50cm cog & hope I don't slip and catch my nuts on that spinning "circular saw" in the middle of the wilderness!

Edited by user Sunday, 24 January 2016 10:30:15 PM(UTC)  | Reason: add video links, and lol

Ok... I know nothing about science (in electronics and that term) I prefer biology

Yes it will be hard work standing and pedalling against little resistance, taller gearing will help and you could introduce some extra resistance maybe something adjustable on the crank spindle perhaps.

Good job Iggy

Well water and electricity are a pain.
Did a bit more investigating of the solar panels they will be about $200, and are prone to water damage (imagine a light shower coming over when I'm down in the bush - or some water blowing off the trees and 'poof' there goes my solar panel (the panel is resistant, problem is when water gets into any connection while it is in operation).
Also they don't maintain a regular voltage when sky is overcast - which requires a battery back up to take up the slack.

I expect to be up on mountainsides for 40% of my time - perhaps there would be small creeks but not enough.
But it is a valid idea.

{going off on a tangent here}
Perhaps if I wasn't trying to dive rivers, detect rivers, detect mountainsides, detect deep into bushes and instead more efficiently focuse on one area then my pack would be lighter.
But I need to waterproof detector - so may as well make it submersible. And wetsuit doubles as warmth(has built in hat) if I get cold, and great for simply wading in those cold southern waters. Also wetsuit & swim fins help me cross rivers. The early settlers/prospectors considered drowning a normal common way to die 8{