Fluke Biomedical 6000-528 - Manual (Page 15)

Victoreen 6000-528
Operators Manual
4-4
NOTE
NOTE
CAUTION
The Fluke Biomedical Model 6000-530 preamplifier provides a means of matching your 6000-528
ionization chamber to a Model 6000B, 6000M, 4000M+, or 4000+ so that exposure and exposure rate
values may be read directly from the instrument display. The 6000-530 must first be adjusted to
accomplish this.
The following describes how to construct the calibration fixture, and how to obtain the value of chamber
sensitivity.
1. Turn on the host instrument and allow 3 to 5 minutes to warm-up. The preamplifier automatically
powers up when it senses high voltage from the host instrument.
2. Zero the host instrument, with nothing connected to the input, by selecting the fluoroscopic (rate)
mode and waiting until the display stabilizes.
If the calibration fixture hasn't been constructed,
construct the fixture as shown in the schematic
below (Figure 4-1):
Ensure that the 9 V DC battery is installed with the
correct polarity when constructing the calibration
fixture.
Figure 4-1.
3. Connect one end of a coaxial cable to the BNC connector on the calibration fixture. Connect the
other end of the cable to the input of the host instrument.
4. Adjust the potentiometer on the calibration fixture until the instrument reads 1.00 R/min.
5. Disconnect the calibration fixture and make no further adjustments to the potentiometer. If the
potentiometer is moved, re-perform steps 4 and 5.
6. Turn off the host instrument and attach the preamplifier to the host input. Turn power on and allow
to warm up for five minutes.
Do not adjust the CAL potentiometer located on the
preamplifier. Doing so will change the factory
calibration.
NOTE