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I built a bicycle generator as a fun project that would give me some incentive for using an indoor trainer when the weather was too lousy to ride outdoors. It is instructive to hook up various appliances to it to see how much effort is required to power everyday things, including audio components. Along with the bicycle generator I made a crystal-controlled sinewave inverter that can use a highly-varying dc input (35V-125V) and produce a regulated 120 VAC at 60 Hz. I also built separately a single-ended 6K6 headphone amp and power supply for a CD player that can take a similar range of highly varying input that is independent of the inverter. I did this because I wanted to use another feature that I built into the sinewave inverter that allows me to program it to vary its output from 120 VAC down to 40 VAC. This allows me to have a variable workout on the bike while not affecting the operation of the audio stuff. I can program the inverter with an analog voltage from an arbitrary signal generator I have, or use a digital counter plus D-A circuit I built into the headphone amp. I have a purchased digital display meter on the bike that shows volts, amps, watts and energy.

In addition to the audio stuff, I normally have a window-type cooling fan and perhaps a small incandescent light bulb hooked up to the inverter for additional loads to my legs. When the program tells the inverter to put out less voltage, the fan slows down and I don't need as much cooling. When the program tells it to goose my required effort the fan and bulb get up to the full 120 V and I have to work hard and get maximum cooling to my body.

Anyway, at some point it might be fun to have an audio meet at my place and have some sort of contest to see who can power an audio system for one side of an LP. I checked out a 10-watt ZOTL amp I have (push-pull 6K6s) today and it, plus the inverter, uses only 60 watts at idle and I don't think my turntable uses more than about 10 watts, so easy pedaling. Still would need a phono pre; maybe someone has a small ss one that would draw little power?

You never cease to amaze me David.

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I have too much stuff - https://www.pleasebuymystuff.com

Dave,

I'm happy to ride it for an LP side if you can get the seat post low enough for me to reach the pedals, cause you have probably a 40" inseam.

Some photos

I have a Hagerman Bugle 3 that runs off a small smps. Shouldn't add too much load.

David

Dave, what is the most miles you have ridden in a year?

I think it would be a sensation at the next CAF.

ray

David,

You are a wild man!

I always wanted to do what you've done: I thought it would be a lesson for my kids when they were growing up - how much effort is one willing to exert for certain things. It looks like a blast and I'd probably die trying to play an LP!

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- Guy

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Walt

Outrageously cool and nerdy