Images of items I have purchased (except trainers [no feet pics])

Commissario
Joined
16 Oct 2002
Posts
342,176
Location
In the radio shack
I wonder if I can take the output of a Joule thief and use it to drive a 3909 flasher circuit - I don't see any reason why not. I've been rummaging through the junk drawer for some 2N3904s or equivalents but I don't have any so I've ordered a handful from eBay for pennies. I'll just knock one up on the end of that piece of breadboard and feed the output into the flasher.
 
Caporegime
Joined
20 Jan 2005
Posts
45,767
Location
Co Durham
Came earlier than expected.............

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Associate
Joined
8 Nov 2012
Posts
1,421
I wonder if I can take the output of a Joule thief and use it to drive a 3909 flasher circuit - I don't see any reason why not. I've been rummaging through the junk drawer for some 2N3904s or equivalents but I don't have any so I've ordered a handful from eBay for pennies. I'll just knock one up on the end of that piece of breadboard and feed the output into the flasher.

No harm in trying, although depending on the flasher, it'll be 3 volts at roughly 45000 hz .. will the flasher just stay on as it think the 3 volts is it just being turned on.
 
Soldato
Joined
15 Dec 2008
Posts
2,700
Location
London
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New coffee machine. Nespresso this is not. Already gone through most of a bag of semi-fresh beans just dialling it in. Not quite there yet. Then I need to work on my milk frothing. I scalded the first couple of goes.

My perfect flat white is there somewhere though.

I have this very machine - it's a great piece of kit.
 
Associate
Joined
1 Dec 2004
Posts
2,250
Location
Glasgow, Scotland
A Joule Thief ... LEDs won't work of a voltage under 3 volts, but when you turn a transistor on with a 1.5 volt battery, you get a spike of 3 volts before it drops back to 1.5 volts, add in a ferrite bead and you can have a resonating circuit and you can turn an transistor on and off at 40000Hz .. so you can get 3 volts out of a single 1.5 volt battery. Joule Thiefs also work long after a battery in dead, meaning you can run an LED for months off a dead battery, one bloke I read about had over a year.

Very clever - and thanks for explaining that in simple terms bud :)
 
Man of Honour
Joined
11 Mar 2004
Posts
76,634
As im so bored, waiting to see what happens with work, thought i would entertain mysefl.
So plans for a 78" wingspan B52
a small section, its on 2 xA0 sheets.
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