Cheap TX/PI coils from old CRT!

[BJ]

It came to my mind some time ago that from
old PC screens there is a cabling called
"deflection cable". (or someting!!).

Its purpose is to demagnitzie the CRT, when you
push the demag button on yor scren a large pulse
are sent out to the cable who creates a magnetic
field and the screen goes,,klonk,,,gzhzh!

Well, this cable is very solid, sturdy,
simply hard whinded isolation tape or what-
ever and some has even several layers of isolation making them very rugged.

I have dissasembled several old CRT's and
some of them are can be used as coils for
PI detectors but most they are nice as TX
coils in send-recive detectors!!

Just whanted to mentioning this as a el cheapo
source of allready made coils for your detector!

REG (spelling crap, but message sent!)
BJ

[kt315]

I would be not especially amazing if in future one will offer use monitor's yoke for magnetometer project.

regards

[simeon webber]

sadly not

the yoke on a crt
most {80 - 90 %} are composit ferrite {fused dust {mostly left over from nucular reactor construction and other machinemade solid bits dusts }

this fully scatters any procession before it begins

you need solid ferrite

from a 1950s tv or a very old crt {navy army} radar {if you can find one that uses a yoke}


or from a microvitec monitor mrk 1

the dead givaway is the ferrite is black and shinny and hard stone like appearance not dull and gray and dusty looking all the time


i think he means the degause coils

for pi
but again too many turns and the wrong material


for coil i use good old bog standard gold / silver plated nickel computer development hook up cable .6mm plastic coated

this is a nice diameter for gold and silver pickup

and rejects things like aluminum very well giving a dip around aluminum with out affecting gold or silver

copper is for magnets and degause coils

and the kettle

for a nice cup of tea.....



link too latest autotrax version v1.18



Click Here (http://www.autotraxeda.com)

[simeon webber]

for the benifit of those who instantly dismiss what i said

i think youll find .6 mm gives a better guage and the silver or gold plate gives the wire much less surface resistance
this gives a very much brighter field and
becouse
1} its .6mm
2} its a lower resistivity than copper and less resistance you get a much higher q but a flat bandwidth of 3 times more than copper
so with multicoil gives all allover better responce if you use three layer coils
after some concideration
i made a coil from this today

a three layer coil wound and a winder i made {nice pages carl tnx}


it uses
28us drive fet 1>>ccw28T cw ct23T ccw 28

[simeon webber]

overall dia of the coils i wound is 19.5cm
circles inner dia