August 2021
Beginner
128 pages
5h 36m
English
Content preview from Make: Volume 78
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
AUDIO FREQUENCY LIGHT
TRANSMITTER AND RECEIVER
Figure
B
shows a light transmitter that applies
a stream of pulses to an ordinary red or near IR
LED at a frequency determined by R1. The values
shown provide a light beam that’s modulated at
about 600Hz.
Figure
C
shows a simple light receiver that
will detect the pulsating beam from the LED and
convert it into an audio tone. You can use this
TIME REQUIRED:
2–5 Hours
DIFFICULTY:
Easy
COST:
$15–$50
MATERIALS
All parts are widely available online.
» Solderless breadboard
» Hookup wire
» 9V battery and battery clip
» CdS photoresistor aka photocell. See text
for details; RadioShack offers a ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.