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I’m building a propeller balance
meter. This unit was designed and
built for in-house use at Rockwell
International (North American Aircraft
Corp.) Columbus, OH.
There were approximately 200
additional units that were built for
Rockwell's Aero Commander dealers
around the late 1960s. It uses a
velocity type pick-up which is what I
need. Best as I can find out, it was a
type MU 6-7 Pn. B 11032-1.
If anyone knows where I can get
one of these pick-ups or what
could be substituted, I would
appreciate any help; a used or surplus
part is preferred.
Easy to build and program using a
chip like Monolithic Linear integrated
Input voltage: 5V
Equalizer: Seven band or better
Output: 3. 5 mm
And for the hard way, using a
DSP or FPGA to build an advanced
equalizer/gain headset that could be
used in any computer, phone, or MP3
78 March 2013
I lost my hearing at a very young
age and have always struggled with
listening to the audio out phones,
computers, MP3 players, etc. When I
have my hearing aids in and try to
listen, it’s actually worse!
I would like to build an audio
amplifier with a programmable
equalizer, to be connected to the
3. 5 mm audio output jack. I will
connect +5V separately.
The device will be connected to a
PC temporarily through the USB jack
for programming, and then be
Here are my questions:
Is a one stage amplifier enough?
Is it better to amplify first then
equalize, or equalize then amplify?
Who makes the best audio chips?
What software is needed to
program the EQ?
Any suggested readings, websites,
software, forums, etc.
[#10125 - October 2012]
Are there any companies that are
developing an Android device that is
designed to be wall or panel mounted?
I like the operating system and would
like to integrate an Android tablet into
some automation, but haven't found
anything online. My employer would
also like to explore some possibilities
for industrial applications and a panel
mount would work best for them, too.
[#1131 - January 2012]
I’m just starting in electronics and
have taught myself some of the basics
through reading books and building
kits. I’m intrigued with microcontroller
projects and was hoping to get some
seasoned opinions on where to start.
There seem to be several popular
platforms that get most of the attention
such as Arduino, PIC, Stamp, Propeller,
Which is best for a beginner?
Can someone recommend a book
on programming that assumes zero
experience and explains the basics
from the start through getting a simple
project up and running?
Are there any beginner-friendly
online user groups I might join?
Any advice is appreciated.
While it is not exactly a wall
mounted product, the Arduino ADK
(Android Development Kit) is built to
interface with the Android platform. I
hear that the Raspberry Pi is close to
being able to run Android and that
might be an interesting alternative.
#1 There are a number of ways to get
started in MCUs.
In my opinion, Parallax has the
best documentation to use for getting
started. If you don’t want to buy their
packages, you can download the pdfs
and source the parts after looking at
the components, which they provide
in one nice place in their books. If you
use a book such as the StampWorks
book, then you should examine the
schematics for their Professional
Development Board (BS2 version and
not the Propeller version), and buy the
necessary components to build the
experiments. Other BS2 versions are
available such as the Stamp Stack II.
The "What's a Microcontroller" pdf is
also a good starting point.
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