I have a H11AA1 opto coupler that outputs 5 volts (VCC) with no input and 3 volts with a signal in. I want to use one transistor to change the swing from 5 volts to < 0.5 volts.
I know I can do it with a comparator but is it possible with a single trnsistor?
Thanks
Al
PS Forget my question above. Here are the circuits. The one on the left is used for train detection and I have over a dozen on my layout that work perfectly.
The one on the right is supposed to work the same but is very dependent on the type of DIP bridge rectifier used.
A VM18 works - a B40C800DM and a EDI-PL10 don't work. Seems there is not enough voltage drop
across the two latter bridges to fully turn on the H11AA1.
I know I can do it with a comparator but is it possible with a single trnsistor?
Thanks
Al
PS Forget my question above. Here are the circuits. The one on the left is used for train detection and I have over a dozen on my layout that work perfectly.
The one on the right is supposed to work the same but is very dependent on the type of DIP bridge rectifier used.
A VM18 works - a B40C800DM and a EDI-PL10 don't work. Seems there is not enough voltage drop
across the two latter bridges to fully turn on the H11AA1.
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