UNIPOLAR Stepper Motor Driver - Power Miser Version - The main
feature of this circuit is low power consumption in the motor circuit.
This is achieved by only turning on the individual outputs of the driver for
1/10th of a second for each step the motor makes.
The motor only uses power when it makes a step. This would be ideal for a battery
powered system....Circuit for model railroad trains…. [from Rob Paisley's
Model Train web site] |
UNIPOLAR Stepper Motor Driver (74194) - This page features simple
and inexpensive, stand alone UNIPOLAR stepper motor driver using parts that
are available from many sources. The driver is designed
for medium and low speed applications with motors that draw up to 1.0
amperes per phase. This driver provides only basic control functions
such as: Forward, Reverse, Stop and has a calculated Step rate adjustment
range of 0.72 (1.39 sec) to 145 steps per second. (Slower and faster step
rates are also possible. - See notes.)....[from Rob Paisley's Model Train
web site] |
Using "AT" Type Computer Power Supplies - "AT" type computer power
supplies are often used by model railroaders to provide accessory power for
their layouts. These supplies are reasonably inexpensive due to their age
and have been removed from old personal computers. [from Rob Paisley's Model
Train web site] |
|
|
|
Using 1 Transformer For 2 Throttles Why It Cannot Be Done - Circuit for
model railroad trains…. [from Rob Paisley's Model Train web site] |
Using Common Cathode Or Anode LEDs As Bipolar LEDs - Circuit for model
railroad trains…. [from Rob Paisley's Model Train web site] |
Using The 555 Timer With Photocells - This page shows three circuits for
using the 555 timer IC as a photocell controlled train detector.
Scroll down for this circuit design…..Circuit for model railroad trains…. [from Rob
Paisley's Model Train web site] |
Using The LM555 As A Voltage Comparator Or Schmitt Trigger - Uses the LM555
timer or its cousins with other letter prefixes. There can be minor differences
between 555 timer IC's from different manufacturers but they all should be useable for
any circuit. Designed for Model Trains…. [from Rob Paisley's Model Train
web site] |
Variable Period Oscillator (CD4017) - Uses the LM555 timer or its cousins
with other letter prefixes. There can be minor differences between 555 timer IC's from
different manufacturers but they all should be useable for any circuit.
Designed for Model Trains…. [from Rob Paisley's Model Train web site] |
|
[_OLD-ads-dont_upload/OLD I-ADS from web/ad-djandassoc.htm] |
|
Variable Width Pulse Type Throttle - The next schematic is for an advanced
type of pulse throttle. Simply put, as the output voltage is increased by the 10K pot,
a pulse is injected onto the the control voltage at the PLUS input terminal of the
second LM358 OpAmp. As the control voltage increases the width of the pulse is also
increased....[from Rob Paisley's Model Train web site] |
Various LED Blinker Circuits - The circuit uses independent timers to flash
two light emitting diodes. Any time that light emitting diode D1 is lit__light
emitting diode D2 will be switched off. Light emitting diode D3 is on if both D1 and
D2 are off....Circuit for model railroad trains…. [from Rob Paisley's Model Train web
site] |
Various Power Control Delay Circuits - Uses the LM555 timer or its cousins
with other letter prefixes. There can be minor differences between 555 timer IC's from
different manufacturers but they all should be useable for any circuit.
Designed for Model Trains…. [from Rob Paisley's Model Train web site] |
Various Transistor Throttle Circuits - The first schematic is of the Direct
Current power supply for the throttles. Shown is the primary and secondary circuits
and the components needed to power the throttles. As this section of the throttles
uses 120 volt AC power great caution should be taken in this area. All transformers
should be mounted in a fully enclosed metal cabinet and properly grounded.
Transformers for multiple units could be centrally located and the low voltage AC then
routed to each throttle....[from Rob Paisley's Model Train web site] |
Visible Light Blocking Filter - This isn’t an electronic circuit but the
drawing below shows the curve for an optical filter made from exposed color film. The
material blocks most visible light but is very transparent to 880nM infrared light.
Kodak 100ASA is exposed to "cool white" fluorescent light for about 5 seconds. ….
[Hobby Corner Circuit by Dave Johnson] |
Visible Light Photo Detector - In this circuit, when the light falling on
the phototransistor (Q1) is blocked, its conductance will decrease and the voltage
across Q1 will rise. When the voltage rises above 1/2 of the supply voltage the output
of the comparator will turn ON and the LED will be lit....scroll to find this
circuit....[from Rob Paisley's Model Train web site] |
Voltage Comparator - This page will provide some basic information about
voltage comparator integrated circuits and and to act as reference material for other
circuits. These circuits are based on the LM339 Quad Voltage Comparator chip. [from
Rob Paisley's Model Train web site] |
Voltage Controlled Pulse Width Oscillator - Uses the LM555 timer or its
cousins with other letter prefixes. There can be minor differences between 555 timer
IC's from different manufacturers but they all should be useable for any circuit.
Designed for Model Trains…. [from Rob Paisley's Model Train web site] |
Voltage Doubler Input DCC Only Block Occupancy Detector - This circuit
would be used to hold a BLOCK OCCUPIED condition as a train passes out of the block
even if the normal detector is not sensing a train. The Helper circuit uses
phototransistor type light activated detectors to sense that a train is still in the
block, even though the engine has left that block....[from Rob Paisley's Model Train
web site] |
Voltage Recorder - The images shown on this page show circuits that can used
to measure and record with a LEGO® RCX Brick that comes with the LEGO® MINDSTORMS and
LEGO® ROBOLAB robotics sets [from Rob Paisley's Model Train web site] |
VT-5 DCC Block Occupancy Detector - This block occupancy detection circuit
uses a current sense transformer to isolate the detector circuit from the track power
circuit. The output section of the circuit takes its power from an external power
supply and uses a LM555 timer to provide the release time delay and both an Open
Collector and Bipolar output each detector. [from Rob Paisley's Model Train web site] |
Walk Around Control for The Basic Throttle - In the next circuit walk around
control is added to the throttle. A 4 conductor, 22 Gauge stranded cable will allow
the operator to move around with the 'Hand Held Controller' while the power section of
the throttle remains at a fixed location…. [from Rob Paisley's Model Train web site] |
Waveforms, Currents and Voltages For DCC Systems - This page attempts to
show the voltage waveforms associated with model railroad DCC systems as they would be
seen with an oscilloscope. Also methods of measuring DCC system voltages and currents
are shown. [from Rob Paisley's Model Train web site] |
Wire Coat Hanger Cable Guides (E+F) - Here is a way to use old wire coat
hangers to make simple and efficient wiring harness guides that can help keep your
layout wiring neat and tangle free…(design idea added 05/08) |
|