A Calculator is one of the most important tools for electrical engineers. As
an electrical engineer, I need a calculator which is capable of handling
complex numbers   I had been using two HP-42C for more than 10 years.
HP-42C is discontinued now and one of mine is stolen and the other is
broken.  I switched to TI-89 for a while, but the characters on TI-89 LCD
were so small for eyes of 55 years old man. Now I am using HP-50G
which has larger LCD.  

I recommend TI-89, HP-49G+ or HP-50G to electrical engineers. These  
can handle complex numbers for usual calculation and in matrices.  

There are some useful sites for these calculators.

Comparison between TI and HP:         
http://alpage.ath.cx/hptute/compare.htm
http://www.technoplaza.net/calculators/49vs89.php


HP Calculator sites:
http://www.area48.com/index.html
http://alpage.ath.cx/hptute/hptute.htm
http://www.hpcalc.org/
http://www.hpmuseum.org/


TI Calculator sites:
http://education.ti.com/educationportal/sites/US/homePage/index.html
http://www.ti-news.net/
http://www.ticalc.org/

For daily calculations, I prepared some calculators with Excel. They are
useful for me, so probably for you also, If you are interested in, down load
and give it a try.  

My Calculators
Calculator
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