Hi Mauro and all,

Thanks for the notes.  I see your reference to the LX922 &
LX1358 on the web:  The obsolete LX922 seismometer in its
entirety, certainly was a large unit.  Is the same LVDT coil and circuit

board used on such, the same as on the small pendulum LX1358
that you know of?

http://mariottim.interfree.it/doc13_e.htm

Yes, if you can, and want to, it would be interesting to see
just what they used in the LVDT squarish transformer/s inasfar
as whether its precision laid out, or more ~jumbo wound.
They are somewhat large, and I suspect they are salvaged
coils meant originally for another use....but I could always be
wrong.  In a sense, even if they are not precision, it kind of
suggests that other transformers could work also.....but with
a reduced sensitivity compared to precision wound LVDT's
(but still very good overall).


Mauro Mariotti wrote:

> Hi All, I worked very much with this LVDT.It is based on the Phllips
> NE5521N phase comparator.I can supply you the schematic if needed.The
> cost of the unit is 50$ for the circuit and 50$ for the mechanic
> tobuild up a complete horizontal sensor like to S-G type.I never
> disassembled the LVDT coils to but I can do it I have some sparepart
> in my lab.



Hi Mauro and all,
Thanks for the notes.  I see your reference to the LX922 &

LX1358 on the web:  The obsolete LX922 seismometer in its

entirety, certainly was a large unit.  Is the same LVDT coil and
circuit

board used on such, the same as on the small pendulum LX1358

that you know of?
http://mariottim.interfree.it/doc13_e.htm
Yes, if you can, and want to, it would be interesting to see

just what they used in the LVDT squarish transformer/s inasfar

as whether its precision laid out, or more ~jumbo wound.

They are somewhat large, and I suspect they are salvaged

coils meant originally for another use....but I could always be

wrong.  In a sense, even if they are not precision, it kind of

suggests that other transformers could work also.....but with

a reduced sensitivity compared to precision wound LVDT's

(but still very good overall).

 
Mauro Mariotti wrote:

Hi
All, I worked very much
with this LVDT.It is based on the Phllips NE5521N phase comparator.I can
supply you the schematic if needed.The cost of the unit is 50$ for the
circuit and 50$ for the mechanic tobuild up a complete horizontal sensor
like to S-G type.I never disassembled the LVDT coils to but I can do it
I have some sparepart in my lab.