[Ronja] Testing switching time of an LED

[Deepak Mishra]

You are probably right Pramod,
But my aim like many other people trying to build RONJA
is to get a GPLed communication system working for a specific purpose.
and may be with some help from people like you I could learn some
electronics ?

I am in Ranchi,
Kwality Photons in Delhi manufactures super flux LEDs,
are HPWT-xxx available in India ?

Cheers,
Deepak


On 21/03/2008, Pramod yaduvanshi <pkyaduvanshi at gmail.com> wrote:
>
> Dear Deepak ,
> Then you are wrong person trying out your hand on ronja !! use a simple
> signal generator or fucntion generator to test the LED !!
> Which city are you in ? Superflux LED are available in India
> PK Yaduvanshi
>
>
> On 21/03/2008, Deepak Mishra <xask.linus at gmail.com> wrote:
> >
> > Sorry man , but I do not know how to generate a pulse !
> > What signal source do I use ?
> > I have no practical experience in electronics
> >
> > Regards,
> > Deepak
> >
> > On 21/03/2008, Arun Krishnan <arunk at speedpost.net> wrote:
> > >
> > > Hi Deepak,
> > >
> > > I don't think a 555 can clock to the 10Mhz you'll need to test your
> > > LED
> > > at.
> > >
> > > But I'm thinking you can measure the rise and fall time just by a
> > > single
> > > pulse and a CRO that has enough resolution.
> > >
> > >
> > > Regards,
> > > Arun
> > >
> > >
> > > ----- Original message -----
> > > From: "Deepak Mishra" <xask.linus at gmail.com>
> > > To: "Twibright Ronja" <ronja at lists.pointless.net>
> > >
> > > Date: Fri, 21 Mar 2008 20:00:19 +0530
> > > Subject: Re: [Ronja] Testing switching time of an LED
> > >
> > > Thanks ,
> > > I had this basic idea in mind that I must apply a fast input square
> > > wave
> > > signal to the led and check the output using a scope on the photo
> > > diode.
> > >
> > > But the basic problem is I am such a new bie that I am not sure if i
> > > should
> > > connect
> > > the photo diode directly to the oscilloscope and with resistor in
> > > series
> > > or
> > > what ??
> > >
> > > And how do i generate a square wave signal of the desired frequency ?
> > > I have heard of the 555 timer, do I have to use the breadboard ?
> > >
> > > I good with software, but not so good at hard ware, I hope you get the
> > > idea
> > > ?
> > >
> > > Thanks anyway!
> > > Cheers,
> > > Deepak
> > >
> > >
> > > On 21/03/2008, Arun Krishnan <arunk at speedpost.net> wrote:
> > > >
> > > > Hi Deepak,
> > > >
> > > > You'll need to hook up the LED to a simple square wave generator and
> > > use
> > > > a fast photodiode connected to a CRO to measure how fast it is
> > > > switching. There are other methods where you could program something
> > > > like a microcontroller to measure it, but the easier way would be to
> > > use
> > > > a CRO.
> > > >
> > > > Regards,
> > > > Arun
> > > >
> > > >
> > > >
> > > > ----- Original message -----
> > > > From: "Deepak Mishra" <xask.linus at gmail.com>
> > > > To: "Twibright Ronja" <ronja at lists.pointless.net>
> > > > Date: Fri, 21 Mar 2008 19:13:44 +0530
> > > > Subject: [Ronja] Testing switching time of an LED
> > > >
> > > > Hi all !,
> > > >
> > > > As always, I am having trouble find the LED HPWT-xxxx-xxxx.
> > > > So I am going to test some LED manufactured in my country (India)
> > > easily
> > > > available at low costs.
> > > >
> > > > I mainly want to test the rise/fall time of the LED and its not in
> > > the
> > > > datasheet.
> > > >
> > > > I am an electronics newbie, so could somebody point me to an
> > > electronic
> > > > circuit and a way to measure
> > > > the rise and fall times of the LED ?
> > > >
> > > > Cheers,
> > > > Deepak
> > > >
> > > >
> > > > --
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> > > > Ronja at lists.pointless.net
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> > > >
> > >
> > >
> > > --
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> > >
> >
> >
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> >
> >
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