Hi Eric and MrAl,
I have read the little discussion between you both (hehe).
MrAl, thanks for joining this thread and giving your input.
When I initially put the circuit together, I had already removed the R4 for the LM358 as I thought it was not needed. I also knew about the missing resistor for the base of the transistor (I'm using a BC548 instead of 2N2222 by the way)... but thanks! I haven’t yet tried your ‘diode’ suggestion though.
Guys, I cannot replicate! Maybe I’m having a blonde day, but this is starting to do my head in! Perhaps I don’t understand the diagrams, or maybe it’s because you haven’t included a battery when you were testing it (which could explain why I’m having problems).
I was kindly wondering if you could do another schematic and this time include my fuse/switch/diode/battery setup and show me how you wire up the LM358 to it, and also the LM317. It sort of works and it sort of doesn’t??
A couple of questions for you:
1) I really don’t understand why I need to connect the LM358 power pin to the battery and not to the LM317 output. Connecting it this way is causing problems… If you observe my existing circuit (see attachment), the ‘Charging’ LED will come on thinking that the battery is drawing current when it’s not, when in fact it’s the LM358 drawing the current.
Also, multimeter shows a huge voltage drop because of this (I don’t like it!).
Connecting the LM358 to the LM317 instead eliminates both of these issues.
2) What is supposed to happen when say, the fuse blows? Is the buzzer supposed to turn on straight away? What if the fuse is replaced? Is the buzzer supposed to turn off straight away? Or do I expect a delay?
By the way, I have attached my existing power supply/charger schematic for you to observe.
Thanks again so much.
Jason.
I have read the little discussion between you both (hehe).
MrAl, thanks for joining this thread and giving your input.
When I initially put the circuit together, I had already removed the R4 for the LM358 as I thought it was not needed. I also knew about the missing resistor for the base of the transistor (I'm using a BC548 instead of 2N2222 by the way)... but thanks! I haven’t yet tried your ‘diode’ suggestion though.
Guys, I cannot replicate! Maybe I’m having a blonde day, but this is starting to do my head in! Perhaps I don’t understand the diagrams, or maybe it’s because you haven’t included a battery when you were testing it (which could explain why I’m having problems).
I was kindly wondering if you could do another schematic and this time include my fuse/switch/diode/battery setup and show me how you wire up the LM358 to it, and also the LM317. It sort of works and it sort of doesn’t??
A couple of questions for you:
1) I really don’t understand why I need to connect the LM358 power pin to the battery and not to the LM317 output. Connecting it this way is causing problems… If you observe my existing circuit (see attachment), the ‘Charging’ LED will come on thinking that the battery is drawing current when it’s not, when in fact it’s the LM358 drawing the current.
Also, multimeter shows a huge voltage drop because of this (I don’t like it!).
Connecting the LM358 to the LM317 instead eliminates both of these issues.
2) What is supposed to happen when say, the fuse blows? Is the buzzer supposed to turn on straight away? What if the fuse is replaced? Is the buzzer supposed to turn off straight away? Or do I expect a delay?
By the way, I have attached my existing power supply/charger schematic for you to observe.
Thanks again so much.
Jason.