Let's Make Robots!

Parts Prices (In US Dollars)

Here is the analysis I have done so far. I didn't look everywhere, but I did learn 2 things.

  1. You can't buy everything from 1 place
  2. It is cheaper if you buy from outside of the US on some parts

Here goes my summary: (For all intents and purposes, when priced in £ double it for US dollars. It is a bit less than double, but after your credit card company charges a fee to convert the purchase it will be close to double given the current rate of exchange on 5/7/2008)

Starter Pack (Picaxe 28 with USB cable)

PICAXE Sound Detector Circuit



The circuit above is how to hook up a microphone to a picaxe to either have it detect the presence of sound (using a digital pin) or the sound level (readadc). The question I have is in a couple spots it connects a capacitor to the middle of a resistor. Does this mean you connect it to both sides of the resistor?

PWM Question with PICAXE 40x1

The 40x1 has 2 PWM pins. I have the code pwm 1, b2, 1 but I think I need to tell the picaxe that I want to use the pin as PWM since it can also be an output or input pin. Any ideas?

Admin Edit:

Wherever you see Admin Edit: in a post it is because as I see posts that need cleaned up (title changed, useless posts removed, etc.) I am editting them and cleaning them up. We need to cut down on posts that have no relevance to the original post. This just makes too much to read for those who are catching up and doesn't help anyone. If you see a post that needs some cleaning send it to me as a private message and I will look at it.

LM3914 Dot/Bar Display Driver Question

I got some of these because I thought I could use it on a project I am working on as well as one on the drawing board. I will admit I haven't read the entire datasheet word for word but I have looked for the part that talks about how to pick which one of the 10 LEDs hooked up that I want lit and to what levle I want it lit (really bright or barely visible).From what I read I thought it could have 10 LEDs connected and light anyone of the 10 and to a certain degree of brightness. Maybe I was wrong.

Movie Editor Recomendations

I have a video recorder that does HD, but the software that comes with it will edit th emovie and change the resolution to 640x480 instead of the original resolution of 1280x720. Anyone have a recomendation for a video editor that is free or fairly cheap that will edit HD vids without changing the resolution and if possible also allow the video to be cropped so it will only show the robot and not everything around it if the video is farther away.

 Windows Movie Editor changes the resolution so that isn't an option. The video editor needs to work in XP or ubuntu.



Is anyone here good with diptrace? I am going to make a board for my led matrix when I start working on it but I need to create a tri-color LED using the specs found here. Once I finish the project (still waiting on LEDs) I want to solder it all on a professionally looking board. Perf board has holes that are too far aprt for the tri color LEDs. I need a quick walkthrough on how to make a component with specific dimensions.

How to Make LEDs Brighter or Dimmer Using PICAXE 40x1

I have an idea for my next project after my color sensor and Mr Basic kit, but I need to control a ton of LEDs using 3 picaxe 40x1s. I need to be able to adjust the amount of current to the LEDs using the out pins of the PICAXE 40x1. I know I can use resistors, but I need the pic to be able to adjust them on the fly. Any ideas? I was looking at PWM but the manual says it is x2 only. I also need to use every out pin on the picaxe 40x1 as well as converting the in/out pins to out. Basically I will be controlling 144 tri color LEDs and select the brightness of R G and B to make a custom color.

How to Hook Up a Potentiometer

I googled it and I still cant measure the resistance of a pot using a multimeter. I put 4.5volts on the left pin and tried to measure using the middle pin and the right pin and nothing. What am I doing wrong?

Tri-Color LED Resistor Question

I've seen Oddbots tutorial about LEDs and picking the right resistor, but since this LED costs a few bucks and the wordage is different on Radio Shacks parts I want to make sure I have it right.

Supply coltage is 5 volts
Forward Current 30mA (green/blue), 50mA(red)
Forward Supply 3.5 volts typical, 4 volts max (green/blue); 2 volts typical, 2.6 volts max (red)