Re: HP 9821 - display and tape transport issues #VintageHPComputers
It’s some time ago and I don’t remember which LDR I ordered.
I looked at epay and found several sellers who sell 5mm LDR’s. So the best thing to do, is looking at the datasheet which one fits the best.
Important is R-light < 2k and R-dark is high as possible, the comparator switches at ~2.5V to get a good switching characteristic it’s important to buy a LDR with a wide Resistance range.
Van: VintHPcom@groups.io <VintHPcom@groups.io> Namens mariuszmleczko@...
Hmm...so it seems to be defective ? Rik can you propose some available on the market phototransistor for replacement ?