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From: derrick@ritcsh.csh.rit.edu (Derrick Williams)
Newsgroups: sci.electronics
Subject: TAB books
Message-ID: <1991May6.003753.8745@ritcsh.csh.rit.edu>
Date: 6 May 91 00:37:53 GMT
Organization: Computer Science House @ RIT, Rochester, NY.
Lines: 26


 I picked up a TAB book, "30 Customized Microprocessor Projects" by Delton 
T. Horn. It is listed as TAB book # 2705. It looks like a good introduction
to microprocessor devices, but I noticed some glaring errors in the schematics
shown in the book. I'm not an electronics expert (hence buying this "how to"
book), but the power supply the book suggests I build has an error in the
rectifier section, in which the connections are rotated 90 degrees, so that
the transformer is shorted out. The recommended rectifing diodes, 1n4004's,
not inappropriate as they get hot, and only 2.53 volts leave the rectifier
(6.3 input voltage). I looked them up in a Mouser Electronics catalog, and
these rectifiers are rated at 1A with a 400prv (peak reverse voltage, I think),
and this is on a 3 A transformer. The diagram is on page 155. Also, what should
be labled as "-" on the rectifier is connected to ground.
 On page 165, the 7474 daul d-type flip flop has its pins incorrectly
labled. There are two pins labled "4". They should be 4 for the input signal,
and 6 for the output.
 Has anyone had a similar experience with this author, or with TAB books in
general? I've become a bit skeptical about building projects from this book
as my power supply started to smoke when I built it as described.
I would hate to think TAB books made similar errors in other books, like
"Build Your Own Cutting Laser". 

                                                      Derrick
     
 PS. What's the best diode to get for a rectifier for a 6.3v 3amp output
voltage from a transformer? How about a 1n5408?