Bicycle audio system

On Aug 31, 9:53 pm, "[email hidden]" <[email hidden]>

Quoted message said:

Anyone have useful information for creating a bike audio system?

The one I have in mind is a couple small speakers connected to a
headphone jack and powered by a dynamo hub/nicad (sp?) battery
source.

There is plenty of information on DIY audio but not a lot on dynamo
hubs, and all of that is about lighting.

The biggest problem with hub generators is that the power output is
not the least bit consistent and on the higher end units is
alternating current. Portable electronics like to see steady DC power.

If/when I get around to having a new front wheel built, it will have a
SON dynohub for use in a battery charging and running a Ham radio
transceiver. However, this is going to be a non-trivial task involving
a charge controller and regulator, and a lot of other stuff that will
add a lot of weight and possibly drag. The reason I'm not in much of a
hurry is because the electronics will need to be built from scratch. I
was thinking of using something from a windmill system, but they are
usually integrated into the nacelle and not very portable. Solar
charge controllers usually shunt power back to the solar panel when
the battery is charged, which will cause the hub to act like a brake
(and burn up). And, of course, it all costs money. The advantage is
that there is a lot of potential energy going to waste on downhill
braking, and it might be a fun project.

With today's cell phone standby times measured in days, it may make
sense to get a phone that plays .mp3 files and use a roll up solar
panel with appropriate adapter for a few hours. As for the speakers,
headphones make a lot more sense. I remember having one of those cheap
AM radios on my bike as a kid, and it was nearly impossible to hear,
even at full volume.