Superpositioned : Comments

Comment on Doorknob touch alarm by teja

Thu, 05 Nov 2009 06:23:04 -0800

hey its very nice.I have to do this as project.Please help me

Comment on Measuring the speed of light with Chocolate Chips by Katy

Tue, 03 Nov 2009 17:39:28 -0800

Hi I did this as well and found that the hotspot was in only one area. What is the explanation for that

Comment on A low power, long life LED flashlight circuit by zinaung

Fri, 16 Oct 2009 01:40:11 -0700

I am zinaung .My education is 2nd year B.A(geog). My hobby is construction of simply circuits ,so daily reach to circits your website is most attractive as learning pages I think.Can your some circuits sent me? If you will link me,my G-mail is “bozinaungkalate.sgmm”.

Comment on Doorknob touch alarm by piyushmlk@yahoo.co.in

Tue, 13 Oct 2009 10:36:51 -0700

why can’t it be used for metal doors

Comment on BigDog: A heavy duty quadraped by avinash

Fri, 25 Sep 2009 10:06:05 -0700

i am found of robots i would like to construct like on of urs

Comment on Doorknob touch alarm by Mehbub

Thu, 27 Aug 2009 11:28:05 -0700

What is alternative to ZVNL110A? will any Mosfet work?

Comment on Always be wary of schematics by Earthscum

Tue, 21 Jul 2009 09:41:45 -0700

Was just reading through this and had to chuckle. I ran into a problem of a schematic for Boss DS-1 simply having the inv/noninv inputs marked backwards… however, they still had the pins numbered correctly, and after confirmation with a couple other partial schematics, managed to build the correct op amp stage that didn’t rail at what sounded like maybe 4-5 gain at the most, heh!

Comment on Getting started with the Atmel AVR by learner404

Mon, 13 Jul 2009 09:36:08 -0700

Warning: Could you please delete the above URL I gave in the comment a long time ago (this domain is now squatted by an “adult” site).

The correct address is now: http://sourceforge.net/projects/liberlab/

Thanks for your comprehension.

Comment on Doorknob touch alarm by jbridge@makelengineering.com

Mon, 25 May 2009 17:11:21 -0700

Hey! That buzzer you used in this project would be perfect for something Im desigining. Could you e-mail the specifics on it? (i.e. who u ordered it from, the name of it, model. Im getting the impression its s star mmb-01 buzzer, but am having a hell of a time finding anything on the web.)

Comment on A low power, long life LED flashlight circuit by Flashlight z

Mon, 13 Apr 2009 17:48:10 -0700

Great DIY guide. Only thing lacking is the apparent battery life. How would the cost compare to the battery drain versus just buying commercial?

Comment on Measuring the speed of light with Chocolate Chips by Beefyboy

Tue, 17 Mar 2009 13:12:33 -0700

my experience with this test is that all of the modern microwaves randomize where the radio waves are. Are you aware of any microwaves with standing waves that remain in the same place?- other than that- great experiment!

Comment on Doorknob touch alarm by Matthew

Wed, 04 Mar 2009 11:14:15 -0800

The parts can be found at a local electronics components shop. You can also try to find the appropriate components online at http://www.mouser.com or http://www.digikey.com

Comment on Doorknob touch alarm by johanna

Wed, 04 Mar 2009 11:05:17 -0800

where can i find the parts list of this project? im so interested with this particular project!

Comment on A low power, long life LED flashlight circuit by Acme Fixer

Mon, 22 Dec 2008 20:59:52 -0800

The two transistor circuit, Q1 and Q2, is basically a blocking oscillator like the Joule Thief. Remember that this circuit works by regulating the output to a constant voltage, which isn’t really what the LEDs want. The higher the output voltage, the higher the rectified voltage across C2, which then restricts the current thru the JFET, and hence to Q2 and the V boost circuit.

I’m not sure this circuit requires a JFET, other than to limit the current, but the same thing can be done with a resistor and a transistor. You can remove the JFET and replace it with a 1k resistor, and the circuit should work okay, since that’s the same circuit seen in other articles. But the first thing to do above all else is to replace Q2 with a 2N4401, since a 2N3904 can’t handle the high peak current over 100mA that is required. Also it doesn’t seem necessary to use a Schottky diodes, a 1N4148 should work okay, since there is just a very small current thru the diode.

Just tack solder it together and see what happens when the parts are changed. Have fun.

Comment on Doorknob touch alarm by Shashank

Fri, 05 Dec 2008 04:18:41 -0800

I wonder if this small circuit can add protection to my Motorcycle. Is it possible to use it with motorcycle, as motorcycle has more metal area than knob.

Also is there any substitute mosfet for ZVNL110A? can i use BS170?

Comment on Measuring the speed of light with Chocolate Chips by MikeHersee

Sat, 08 Nov 2008 16:03:36 -0800

My mate and I tried it with a big bar of Cadbury’s chocolate. To our disappointment our first noticeable gap between melting points came in at about 11 cm, thus his microwave was allegedly producing microwaves at nearly twice the conventional speed of light. We tried it for longer but it ended up making the whole bar liquid without giving us any more measureable points. So we decided next time we’d used chocolate chips, and spread our melted chocolate bar all over some cherry ice cream instead.

Comment on Measuring the speed of light with Chocolate Chips by Matthew S

Sat, 08 Nov 2008 08:12:41 -0800

We could take the microwave apart (or a similar one we don’t need anymore) and reverse the electronics to learn what the frequency is from whatever timing source your microwave uses (or reading the label on the transmitter)

Cool experiment, I’ve got a 10 year old who will find this exciting and tasty.

Thanks

Comment on Doorknob touch alarm by mia

Tue, 04 Nov 2008 15:51:08 -0800

hey! i`m doing this sort of an investigative project. need help. :) anyone care to educate me more? thanks!

Comment on Powering LEDs costs mere pennies by Orpheus

Mon, 03 Nov 2008 07:00:06 -0800

Great idea! You can use lemon juice, as it produces 1v per cell…

Comment on Vex Robotics Starter Kit - $179.99 by Sandra

Sun, 12 Oct 2008 12:34:03 -0700

Is anyone interested in never opened VEXROBOTICS V.5 Kit, Wheel Kit, Gear Kit, Motor Kit, Servo Kit, Limit Switch Kit never opened?
Sandra