A simple test circuit to fault find audio and radio equipment. Can be
used to inject a square wave signal, rich in harmonics, or used with
headphones as an audio tracer.
Electronic circuit : Beat Balance Metal Detector
A Beat Balance Metal Detector made from discrete components.
Electronic circuit : Coil Coupled Operation Metal Detector
A Coil Coupled Operation Metal Detector made from readily obtainable components and using an ordinary
medium receiver as a detector.
Electronic circuit : Milligaus Meter
The circuit provides an easy yet reliable way to detect the
intensity of a.c. (or e.l.f.) fields
Electronic circuit : Metal Detector
A single chip metal detecor with a range of a few inches. This is useful for decting nails or screws in walls and floors,
or for locating buried mains cable.
Electronic circuit : Doorbell for the Deaf
This circuit provides a delayed visual indication when a door bell switch is pressed. In addition, a DPDT switch
can be moved from within the house which will light a lamp in the door bell switch. The lamp can illuminate the words
"Please Wait" for anyone with walking difficulties.
Electronic circuit : Hot Water Level Indicator
By andy collinson
A simple device to indicate various levels of hot water in a tank.
A simple device to indicate various levels of hot water in a tank.
Electronic circuit : Electromagnetic Field Detector
This circuit is sensitive to low frequency electromagnetic radiation and
will detect for example hidden wiring or the field that encompasses a
transformer. Pickup is by a radial type inductor, used as a probe which
responds well to low frequency changing magnetic and electric fields.
Ordinary headphones are used to for detection.
Electronic circuit : Static Detector Negative Ion Detector
A sensitive detector for static electricity based around a single Field Effect Transistor It can also be used
to detect the presence of negative ions, or test a negative ion generator.
Electronic circuit : Temperature Monitor
A simple op-amp circuit that will trigger a relay when a preset temperature is reached. Please note
that there is no hysteresis in this circuit, so that if the temperature changes rapidly, then the relay
may switch rapidly.
Electronic circuit : 10 Way Electronic Switch
This is a 10 way electronic latching switch using just two switches. Each output can be latched on and off independently.
Electronic circuit : Toggle Switch (2)
This versatile circuit provides a selection of different switching
modes. It can be used as two entirely separate toggle switches - with
each push button successively energizing and de-energizing its own
relay.
Electronic circuit : Latch Switch
In this circuit a non-locking push switch is used to activate a load.
The load remains switched on until power is removed from the circuit.
Electronic circuit : push-to-make switch
Pushing the button once will energize the relay. Pushing the same button
a second time will de-energize the relay. Any simple momentary action
push-to-make switch will do.
Electronic circuit : A Thermostat With Adjustable Hysteresis
A thermostat doesn't try to maintain a constant temperature. In order to
do so - it would have to keep switching on and off every few seconds.
Instead - it keeps the temperature within a specific range. When the
preset temperature has been reached - it switches off. And it only
switches on again - when there has been a significant change in
temperature.
Electronic circuit : Toggle Switch
This simple circuit will energize and de-energize a relay at the push of
a button. Any type of momentary action push-to-make switch can be used.
Pushing the button once - will energize the relay. And pushing it a
second time - will de-energize the relay
Electronic circuit : Temperature Controlled Relays
The first circuit energizes the relay when the temperature rises above
the preset level. The second circuit energizes the relay when the
temperature falls below the preset level. The two circuits are
practically identical. The only difference between them is the polarity
of the transistor.
Electronic circuit : The schmitt trigger circuit
This circuit uses a single op-amp and the output is triggered by two different voltage levels.
Subscribe to:
Posts (Atom)