Zeiss humphrey HFA II-i series Field Service Manual page 29

Humphrey Field Analyzer II - i General Information
Many of the unique functions that the HFA II CPU PCB supported are now included in the HFA
II - i Backplane PCB. The functions of the Backplane PCB include; the patient switch, touch
screen, camera frame grabber, and video.
FIGURE 2. Backplane PCB Functions and Interconnects
The DAT streamer tape of the HFA II has been replaced with a magneto-optical medium reader
in the HFA II - i. Besides reducing cost, the new HFA II - i drive provides greater long-term
storage of large patient files.
For EMI considerations, the HFA II - i CPU PCB and Backplane PCB are housed in a metal
enclosure. The enclosure is bolted the chassis in the location of the HFA II CPU PCB.
To accommodate the enclosure the rear cover was redesigned. The rear cover does not make
use of 1/4 turn fasteners.
Confidential and Proprietary
Field Service Guide
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