TECHFORUM
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QUESTIONS
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❶ Circuit Design
❷ Electronic Theory
❸ Problem Solving
❹ Other Similar Topics
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94 November 2008
>>> QUESTIONS
Accessing Serial Ports With VB
I am using MSComm32.ocx in an
MS ACCESS application, using VBA. I
need to send and transmit data with
this control. I have the mscomm32.ocx
file installed on my PC, but I have never
transmitted data over a serial port
before this project. Please help.
#11081 Vince Finato
Sunnyvale, CA
Air/Fuel Ratio Gauge
I have an air/fuel ratio gauge
installed in my car. My understanding
of the oxygen sensor is that it has a high
impedance output that ranges from
zero to one volt. The output varies
rapidly through its range, making the
gauge dizzying to look at. Does anyone
have an idea for a circuit that I could
install between the oxygen sensor and
the gauge that would "average out" or
slow the response of the signal to the
gauge? Perhaps a voltage follower with
a capacitor on the output?
#11082 Chris Karnow
Hopewell Junction, NY
Power For Hughes Satallite Dish
I was given an HN7000S dish and
modem.
The DC in is an eight-pin DIN but I
do not have the power supply or pinout
to make it myself.
I know I need to have Hughes set it
up and pay them for service but I'd like
to have it ready — help!
#11083 Tom Marrapode
Laporte, IN
Guitar Tuner
I am designing a microcontroller-based guitar tuner. However, I am
lacking some vital information: What
are the frequencies of the open strings
(in Hertz)? This would seem like a
simple question, but so far I've been
unable to locate this information.
#11084 James Burrell
Trinity, AL
Using A PC Power Supply As A
Stand-Alone Supply
I would like to use a spare PC
power supply as a stand-alone source
for the 5V and 12V it provides. What is
the simplest way to provide the 5V
feedback for a power good signal? Is it
possible to use the PG signal to also act
as a power on light, as well?
Any sources of part numbers
would be appreciated.
#11085
Wes K Miller
Dillsburg, PA
Well Pump Alarm
I volunteer my services to our
local water department (which is all
volunteer except for our Water
Operator). We have three well sites
whose pumps are located at the well
head. These pumps are connected to
variable frequency drives within the
