3
36
6
P
robe Head R
eplacement P
rocedure
8b.Obstetric Probe Head Assemblies Only [e.g. OP2HS, OP3HS]
Whilst observing the probe supply current, adjust PR1 so that supply current = 35 mA.
If 35mA cannot be obtained, set PR1 to maximum current.
Figure 3 : Probe Layout
Vascular
Probe
Obstetric
Probe
T2
T2
PR1
T1
PR1
T1
PR2
+0.2
-0
9. Record this reading on the Device History Record Sheet (Appendix B) along with transmitter
impedance and date code.
(e.g. Date "21st June 1993", Product "OP2", Serial Number "135",
Transmitter Head Impedance "24", Drive Voltage "3V", Supply current “35mA”, Date
Code "TAD").
10.
Check that supply current is;
By adjusting T1,
<35mA for VP4, VP5, VP8, VP10, EZ8
11.
Turn off the power supply and disconnect probe.
7.6 Reassembly Procedure - All probes except D920-P, D930-P, FD1-P
& FD3-P
1. Remove the probe head from the PCB if fitted.
2. Slide the copper screening tube over the PCB.
3. Solder the ground wire(s) to the tube, and tuck the wire(s) into the end(s) of the tube. Fit the
head, taking extreme care not to bend the connector pins.
4. Fit the new case halves ensuring that the locating lugs align with the holes in the head and
end-cap.
5. The probe should now be functionally tested, see Section 8.