🚀 go-pugleaf

In article <5352@whuts.ATT.COM> sw@whuts.ATT.COM (WARMINK) writes:
>> ... Those bulbs are a notorious
>> reliability problem that is being designed out of more recent satellites...
>
>There must be a good reason why LEDs weren't used - 6 years plus isn't that 
>long ago...anybody know why not?

Semiconductors can take quite a while to become space-qualified, and there
is considerable reluctance to change a design that seems to work all right.
I think it was only in the last few years that it was understood that the
bulbs were a systematic weakness.

Also, don't forget that the bird may have been built well before it was
launched -- it's not uncommon to build a batch of satellites and then keep
the last few on the ground until they're needed.

The more recent encoder designs do use LEDs.
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