Homemade proton magnetometer - real tale

[Mikediver]

Hi ApBerg
You are deadly right! This adress is: http://www.pg.gda.pl/org/rekin/
This is side of our diving club. On the right side you must selected :Galeria starych fotografii and in this section: 05-04-02 Stegna.... Yes, this guy in the blue blazer and green rubber shoes is me!
Regards
Mike

[Unregistered]

Hello Denominate books and which you have found the author if that is possible publish a part which you have copied [email protected]

[Mikediver]

Polarization circuit

Polarization circuit. Timer 555 generates polarization voltage. For presented resistors and cap, polarization time is 2.5 sec. Zener diode supress voltage spikes generated during switching off. Coil of second relay is paralelled by the capacitance Cx. This cap delay opening of the second relay. For this period resistor Rx is connected to the coil to obtain smooth current decay. Input of preamp is shorted to ground (9-13 are connected). After discharge of this cap, second relay connecting sensor to the input of preamp and disconnecting ground. Tuning procedure is very simple:

1. disconnect sensor LOW from GND
2. introduce in this place low resistance (c.a. 0.3 ohm, not wire wound!).
3. connect scope to this resistor
4. observe current decay in the sensor coil
5. select Cx to have exponential curve truncated at the current value c.a. 0.1-0.05 Imax (decay curve must be cut off before reaching zero!)
6. Observe in the vicinity of mentioned step to current decay
7. select Rx value only to supress any ringing, (but too low value will smear this part of curve - also not good!).
8. remove low resistor, connect LOW and GND
9. delight with your work and wait to the next part of description