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Hi Peter
The 800mA excitation current turning off through a 15mH inductor is
sure to ring at some frequency dependant on spurious capacitance.
What is the frequency of the 100mS signal you get ? If it is way
off the expected precession frequency expected at you location,
then you have to dampen this signal without killing the wanted one..
I shelved my unit at this same point as you have reached until I
get some time to experiment :-)
Some thoughts are:-
a diode limiting the ringing to 0.7v or so, but this will still
dampen the wanted signal superimposed on the ringing when the diode
is conducting.
A filter to select the wanted mV level signal from the V level
ringing.
A notch filter at the ringing frequency feeding a low impedance
load.
Asking a schoolkid to write a DSP program to retrieve everything I
need from digitising the signal :-)
I wish all in the group a happy holiday season, ( as you might have
guessed , we have just returned from our staff Xmas lunch )
Regards
John Smith
-----------------------------------------------------
Cavalier Electronics
L'Agulhas
South Africa
----- Original Message -----
From: Peter Krengel
To: [email protected]
Sent: 15 December 2000 15:31
Subject: Problem using toroid
The Proton Mag Forum
Hi guys out there!
I build a toroid made of 8pcs PVC waterpipes with 45° angle each
for a PPM.
The toroid has an outer diameter of about 3/4" (18 cm) and its
body, where the coil is winded on, is about
1 3/4" (40mm) thick. The 8 parts have been glued together using
silicone, inside there is about 500ml
(16 fl oz) destilled water which normally is used for filling car
batteries.
I used AWG #24 wire (0.5mm) and turned 6 layers on the toroid
(about 7.5 feet (230m) wire lenght).
It has a resistance of 15.2 Ohms and an inductivity of 14.7 mH. As
I tried to get a signal out of the coil
I "charged"´it with about 800mA current but got only a short
output signal (about 100mS on my memory scope)
which seems to be only a switching "ping" from the filters.
Because of the very short signal I'm afraid that I did something
wrong on the toroid. Can anybody tell me
what went wrong? The electronics has be tested with a signal
generator and scope and it works fine.
Is this short "ping" which startes with a big amplitude and
continuesly run down within 100mS possibly
the signal of the protons? I think its much too short, also if I
increase the charging current to 1.5A
the signal becomes bigger in amplitude but not longer.
Is it possibly a problem if some acetic acid is left in the toroid
coming from the silicone glue?
After each layer I winded some double sided duct tape around the
toroid for fixing the wire, is this
possibly a problem?
Thanks for telling me your experiences! Please mail me at
[email protected]
Best greatings from germany
Peter
The 800mA excitation current turning off through a 15mH inductor is
sure to ring at some frequency dependant on spurious capacitance.
What is the frequency of the 100mS signal you get ? If it is way
off the expected precession frequency expected at you location,
then you have to dampen this signal without killing the wanted one..
I shelved my unit at this same point as you have reached until I
get some time to experiment :-)
Some thoughts are:-
a diode limiting the ringing to 0.7v or so, but this will still
dampen the wanted signal superimposed on the ringing when the diode
is conducting.
A filter to select the wanted mV level signal from the V level
ringing.
A notch filter at the ringing frequency feeding a low impedance
load.
Asking a schoolkid to write a DSP program to retrieve everything I
need from digitising the signal :-)
I wish all in the group a happy holiday season, ( as you might have
guessed , we have just returned from our staff Xmas lunch )
Regards
John Smith
-----------------------------------------------------
Cavalier Electronics
L'Agulhas
South Africa
----- Original Message -----
From: Peter Krengel
To: [email protected]
Sent: 15 December 2000 15:31
Subject: Problem using toroid
The Proton Mag Forum
Hi guys out there!
I build a toroid made of 8pcs PVC waterpipes with 45° angle each
for a PPM.
The toroid has an outer diameter of about 3/4" (18 cm) and its
body, where the coil is winded on, is about
1 3/4" (40mm) thick. The 8 parts have been glued together using
silicone, inside there is about 500ml
(16 fl oz) destilled water which normally is used for filling car
batteries.
I used AWG #24 wire (0.5mm) and turned 6 layers on the toroid
(about 7.5 feet (230m) wire lenght).
It has a resistance of 15.2 Ohms and an inductivity of 14.7 mH. As
I tried to get a signal out of the coil
I "charged"´it with about 800mA current but got only a short
output signal (about 100mS on my memory scope)
which seems to be only a switching "ping" from the filters.
Because of the very short signal I'm afraid that I did something
wrong on the toroid. Can anybody tell me
what went wrong? The electronics has be tested with a signal
generator and scope and it works fine.
Is this short "ping" which startes with a big amplitude and
continuesly run down within 100mS possibly
the signal of the protons? I think its much too short, also if I
increase the charging current to 1.5A
the signal becomes bigger in amplitude but not longer.
Is it possibly a problem if some acetic acid is left in the toroid
coming from the silicone glue?
After each layer I winded some double sided duct tape around the
toroid for fixing the wire, is this
possibly a problem?
Thanks for telling me your experiences! Please mail me at
[email protected]
Best greatings from germany
Peter