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Stir Driver Noise (Serial Suffix A - C only) Advanced
™
Osmometer 3250/Cryoscope 4250 Service Manual
If not, verify that two ferrite beads are present in your unit, as shown in Installation Option A
or B, below.
Can be cleaned up with ferrite bead. Acceptable if stir wire not affected.
If the beads are missing, purchase Advanced Instruments Part No. 91035 and install, as
shown.
If the beads are present and you still have noise as shown in the following charts, replace the
driver transistor PCB522.
Not acceptable. Replace stir wire driver or use ferrite bead
Installation Option A
A
Note For installation option A, two ferrite beads are installed on the white wire exiting the
head shaft and attached to TR2 on the head transition board.