On 2018-05-06 15:15, James wrote:
On 07/05/18 03:01, Joerg wrote:


Note the three big 470uF capacitor in the schematic. That's the
"flicker reduction trick" :-)

Problem is, electrolytic capacitors do not live long in harsh climate
conditions such as the black light enclosure baking in the glistening
Arizona desert sun for hours every week or riding around the Klondike
in a harsh winter.

For me the only proper way of lighting a bicycle is with a
rechargeable battery.

Bull**** alert!

We all know how reliable rechargeable batteries are, especially in harsh
environments, right?


I tend not to visit hell or the inside of an erupting volcano while on
my bikes. I also do not find cycling in Siberia in Januray very enticing.


OTOH, here is an electrolytic cap from Vishay, that has a "useful life"
of 1,000,000 hours at 40C, and 8000 hours at 125C.

https://www.vishay.com/docs/28334/118aht.pdf

(The useful life approximately halves for every 10C increase.)

If the temperature inside the electronics enclosure was much more than
80C for most of the time the light is in operation (E.g. while you're
riding and the light has forced air cooling), the engineer ought to be
shot, and that still gives a useful life of over 62500 hours.


I have started using dynamo/battery combo solutions more than four
decades ago. Works fine. Except now that we have high capacity Li-Ion
technology I no longer use a dynamo (though my road bike still has one)
because one charge allows me to ride for 4-5h with the ship lit at full
power. I ride with daytime lights all the time except on bike paths.

--
Regards, Joerg

http://www.analogconsultants.com/