I want to design an inexpensive
audio graphic equalizer that us older
guys (and ladies) can use with our
radio (ham) gear. What I envision is a
programmable equalizer that can be
programmed to boost frequencies
based on hearing tests. Even better
would be a stereo equalizer that can
be used with a stereo headset to allow
us old timers to hear better.
#9124 Jim Darrough
was going on in the circuit to cause
Currently I am using two thermostats to activate an attic fan: one thermostat to determine a cool outside
temperature and a second thermostat
to determine the attic temperature.
When the differential between the
two reaches the set point of the two,
they both turn on the attic fan, pulling
cooler outside air up and through the
attic. This only works when each
thermostat reaches their "set" point
temperatures. I would really like to be
able to have the fan come on when a
variable differential temperature — say
20 degrees — is reached, regardless of
outside or attic temperatures; also,
only if the attic temperature is warmer
than the outside temperature.
#9121 Vonn Hockenberger
Cedar Rapids, IA
How Long Does My Furnace Run?
I need to see how long my
furnace blower motor runs and track
the overall time in a digital display. I
would need a reset button to reset the
time when needed. I have a switch
that activates when power is sent to
the motor line. Can I get components
and a design or a kit somewhere?
#9122 Jeff Barto
I have a central A/C unit and the
inside fan blower has a control
module referred to as an "r" mod. It
has a few components on it and is
designed to kick-start the fan motor. I
can’t afford the $1,200 to get it
replaced. Can I just replace the bad
components on the module? It looks
like two small capacitors and an electromagnet. It’s a Carrier Tech 200 SS.
#9125 Omar Deeb
Winter Garden, FL
I'm attempting to repair a PC
board for a RadioShack PT Cruiser
remote control car. The IC (20-pin) has
the following numbers printed on the
top: S111g, KJET IC001, OU97112.
In the tech manual, the IC is
identified as KS57C0301.
(1) Program memory is 1K byte
(KS57C0301) and 2K byte
( 2) Data memory is 128x4 bit
(KS57C0301) and 256x4 bit
Parts from RadioShack are no longer
available. Any help in identifying a
substitute would be appreciated.
#9127 Tom Recker
3D Location System
I am trying to build a close-range
3D location system that works within
about a 10 ft square area.
I need X, Y, and Z coordinates
from one fixed point; then record the
points into a computer.
I prefer a laser based system that
records its rotation in degrees and for
both Z and X axis and the length of
the laser to the object for a calculated
1960s’ Tube Amp Volume
When I was in high school, there
was a Newcomb institutional phonograph — 12-inch speaker and vacuum
tube circuitry. My friend pointed out
that when the volume control was not
rotated clockwise far enough, the
music was "thin." There came a point,
however, that with further rotation of
the volume pot the sound became full
and lush. I would love to know what
S-KMS Recliner Chair
I’m trying to repair a microprocessor controlled massage chair,
imported by HWE, Inc., Los Angeles.
ID S-KMS mfg 000101, additional
NEC is the processor manufacturer and has indicated in thier product
description that the processor is a
uPD75004CU four-bit discontinued
part. I am reasonably sure there is an
onboard program, but do not know
enough about it to get it into test
It appears to be completely shut
Monte Sereno, CA
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