Hi!
I've been battling with this one all day!
What I'd like to do is make a kind of automated dimmer for mains AC (240V here) so I thought it would make sense to use transistors.
The issues I have here is:
1. I can't adjust the live voltage - I'd prefer to add the transistor on the live side so I can shut off the live voltage completely (or close enough to completely) for bulb changes. The problem with this is I'm using a 5V switching voltage and that's never going to get enough current from base to emitter to switch the transistor.
2. On the neutral side I've managed to get the positive part of the wave adjusted but not the negative (a diode switches to an NPN between live (via bulb) and neutral for the positive art of the wave and that works).
As I said in the first issue, I don't really want to go with the transistor on the neutral side, I also don't want to have to use a stepper motor and a pot
I'm still quite new to logic gates really but I'm trying to learn.
I haven't tried anything in practise, I've just tried stuff out in an electronics simulator.
Attached is a copy of the schematic I've been trying. There's a space left after D2 where I haven't gotten anything to work. Again, I'd prefer to completely scrap this for a design on the live side.
Thanks in advance!
I've been battling with this one all day!
What I'd like to do is make a kind of automated dimmer for mains AC (240V here) so I thought it would make sense to use transistors.
The issues I have here is:
1. I can't adjust the live voltage - I'd prefer to add the transistor on the live side so I can shut off the live voltage completely (or close enough to completely) for bulb changes. The problem with this is I'm using a 5V switching voltage and that's never going to get enough current from base to emitter to switch the transistor.
2. On the neutral side I've managed to get the positive part of the wave adjusted but not the negative (a diode switches to an NPN between live (via bulb) and neutral for the positive art of the wave and that works).
As I said in the first issue, I don't really want to go with the transistor on the neutral side, I also don't want to have to use a stepper motor and a pot
I'm still quite new to logic gates really but I'm trying to learn.
I haven't tried anything in practise, I've just tried stuff out in an electronics simulator.
Attached is a copy of the schematic I've been trying. There's a space left after D2 where I haven't gotten anything to work. Again, I'd prefer to completely scrap this for a design on the live side.
Thanks in advance!
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