فلزیاب سایه 2022-04-11

Shadow Metal Detector​

For discriminating treasure hunters, we present the Shadow metal locator from
Altek, featuring deep-seeking VLF and discriminating operation



The design of professional quality metal detectors is a
specialist field which up until now the commercial
manufacturers have kept very much to themselves. This design
incorporates many of the latest techniques in push button VLF
discriminators which have hitherto been the subject of well
guarded trade secrets. The detector performs as well as
commercial models costing over £200.
It uses a ready made search head, as a home-made one would
have no hope of giving the results needed for a design of this
nature (would you use a home-made speaker with your hi-fi?).
The search head from Altek enables depths of over 12" for a
single coin to be achieved.
Construction
The use of sockets for IC1 and IC5 is not recommended due
to the increased risk of leakage currents in the push button
circuitry. C12 is a very critical component. Its value is not too
important but it must be of the highest quality, have low
dielectric absorption and high resistance. Polycarbonate types
were used, but polystyrene would be equally suitable.
To keep the design as tidy as possible 20 way ribbon cable is
used to connect the board to the controls. As each colour
appears twice they are differentiated by indicating from which
side of the ribbon they come - either white or black (the colour
of the wire at the edge of the ribbon). Circuit pins are used at all
other connection points so that wires can be attached after

the board is installed in the case.​