CLASSIFIED ADVERTISING $50.00 Per Inch — No extra charge for color.
Classified ads must be paid in full prior to the closing date or the ad will be
placed in the following issue, at our discretion. Minimum charge is one inch with
half-inch increments. No proofs will be sent. Ads to be typeset by Nuts & Volts
must be received by the closing date. Supplied ads must be received by the
artwork due date.
Call 951-371-8497 or email email@example.com for closing dates,
available sizes, and special prepay discount offers.
World’s Smallest 68HC11
tiny (1 by 1.4 in.), light-weight (0.5 oz.)
on-board 5V reg., crystal, & reset chip
choice of 8K or 32K EEPROM
or 32K RAM + 32K EEPROM (64K version)
SCI, SPI, Output Compare and Input
Capture channels, timer, pulse accumulator
all 14 I/O lines and 2 interrupt lines
brought out to versatile 20-pin connector
program in BASIC, assembler, or C
easy code-loading with Docking Module
8K EEPROM (#MS11SP8K).......$49
32K EEPROM (#MS11SP32K)...$77
32K EE/32K RAM (MS11SP64K)$90
* includes MicroStamp11, manual, PC software (assemblers, SBASIC compiler,
MicroLoad utility, and sample programs),
serial cable, Docking Module, & accessories.
Toll-free (USA & Canada):
Visa • MasterCard • Discover • Amex
Beginner to Advanced
Table Of Contents
On Web Site
Hayden, ID USA
Looking for robots?
Continued from page 8
Fonte mentioned in the article that a more sophisticated
filtering circuit would be better. I agree but am wondering if he
has tried anything that he is happier with.
Thanks for any help you can provide. The ARB looks very
interesting and I want to build it as soon as possible. Keep up
the good work!
Grand Junction, CO
Response: The important characteristics of the op-amp in question
are: 1) operate from a single supply; and 2) be fast enough (
gain-bandwidth product >1 MHz). The LMC6042 has a GBW of only 0.1
MHz and is too slow. If used, there can be additional problems at
the high frequency end. The LMC6442 has a GBW of only 9. 5 kHz
and cannot be used. (I used the LMC6082 because I had it on hand.)
The LM6142 is a good substitute. It operates from a single
supply and has a GBW of 17 MHz. It is available from Jameco
and other suppliers in the eight-pin DIP package (check the website at
www.jameco.com). Note: The National Semiconductor
website (and most other IC manufacturers) will often provide
samples for free and/or provide access to small quantities for
evaluation. The important requirements are that you have to
provide a business address and a proper engineering job
description. (A school address will probably work, too.)
In regards to the filtering question, this application seems to
be an ideal project to incorporate a tunable switched-capacitor
filter. There is already a variable high-speed clock available that
is 25 times faster than the output. The July 2007 issue of N&V
(Making Waves) discusses SC filters.
Hope this helps. It’s always good to get feedback from readers.
— Gerard Fonte
September 2007 97