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WELCOME
TO |
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's
HOMEPAGE |
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Practical
Galvanometer Driver ----
Laser show system becomes more and more popular these days. For such a system,
the X-Y scan module is a key issue to success. There are many approaches
of implementation, out of them the second order close loop system with position
feedback leads to better results .... |
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DIRECT
ARTICLE LINK |
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16JUL2007 |
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Vector
Network Analyzer ----
a necessary tool for amateur radio experimenters. A precision analyzer
always needs a wide band high linearity multiplier and two log amplifier.
That kind of multiplier and log amp is expensive and need calibrate over
wide frequency range. The AD8302 from Analog Device is an alternative
low cost solution....
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16JUL2007 |
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Mobile
Phone Activity Monitor
---- Under some circumstance or in some special environment like theater
or classroom, to use mobile phone is prohibited. Use this simple tool, you
can easily locate the phone in activity and can separate different mobile
phone mode: GSM,CDMA and PHS¡ |
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| COPY
RIGHT 2003-2007 by LI
MAO XIANG |
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25JUN2005 |
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As
Accurate As Possible
---- We always ask ourselves "How accurate do we really need in our
amateur activities?" The answer I think should be "As accurate
as possible!"...... |
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20JUN2004 |
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100MHz
to 7GHz prescaler ----
Nowadays, HAM frequency has been extended far beyond several giga herz.
Also we should extend our ability of measurement. Here I designed a divide-by-1000
prescaler for our frequency counter. The circuit is simple, also very useful.... |
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25JUN2005 |
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Synthesized
Signal Generator ----
the first tool you should build. When we make filters, we always want to
know the exactly frequency response---whether it's the same as the simulated
result. Or, when you build a modulator or exciter, also you will need a
precision and stable signal source. Then we made a VHF source with 0.25Hz
step... |
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18Apr2004 |
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High
Performance ADC Converter----Super
low noise and THD, this is just what you need for digital recording. Don't
just complain that 16bit system is not good enough, build this unit and
enjoy the 16 bit ... ... |
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02May2004
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Fractal
Mathematics ----
Does it has anything to do with RF? The answer is YES. The fractal mathematics
has been applied to antenna design for quite a long time. Whether being
prospective or not,it is quite something that we need to pay attention to
... |
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28DEC2003 |
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