I'm trying to understand what should be expected.
Plenty of laser diode output on a test IR photosensor, when first started
exploring there was the usual deep red glow, now no visual red glow but
still plenty of IR on the photosensor when laser is on. Changing laser
lasing mode ?
Focus servo works 3 times but no output from focus processor to initiate
platter motor drive. Monitoring DC at any of the photodiodes, set mid
potential of 2.495V and varies at most 5mV as focus servo activates, but the
5V supply to the focus photo diodes is varying about 5mV. Monitoring
differentially between 2 focus diodes there is less than 200 microvolts DC
variation , is that the normal level of variation ?

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Diverse Devices, Southampton, England
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