I’m back with an update.
I have made a significant change to the circuit. I have removed the Cap-Diode from the trigger leg. Let me explain why I did this…
These test runs take so long to complete so I built a small single transistor circuit to try changing around while the main test is underway. I wanted to try larger caps, smaller caps and higher draw vs lower etc. I figured with a small setup I could get a feel quickly for how changes would affect the larger machine.
Here is a shot of the small circuit. The coil is glued on under the circuit board, it is 44 feet of 22AWG on trigger and power.
So this post is not about this little circuit but I have to say this thing works very well at charging up to 5AH batteries. I have been using it to charge my meter batteries and some AA’s for my telescope. Works very well!
I was changing out caps on this thing and I thought to take a voltage reading across the cap. I did this by hooking the negative to the Primary negative and the pos on the pot leg with the diode leading towards the base. I noticed that at low draw the voltage was high like around 18-22V and you could see the cap fire and recharge, but as I increase the draw the voltage would drop. After a certain threshold you no longer see the cap charging and discharging but rather just steady at a relatively low voltage. I do not know if it actually is still cycling and the meter just cannot sample fast enough or if the resistance just stays fixed at that point and no longer flip flops between the pot and cap path.
Whatever was happening I decided that it cannot be good for charging. I much prefer to see that base getting hit with higher voltage. The cap-diode works great at low draws and as a matter of fact that is how Patrick was using it when he showed it in his video. I had strayed from his method of using it when I decided to crank up the juice. I would still recommend it on smaller systems or if you use low draw. It does a wonderful job of pulse triggering as long as you don’t turn up the juice to much.
Here are some pictures on the big machine where I set the draw low and then high. I went and confirmed that the big machine was behaving the same way.
With a low draw, voltage is high on the cap trigger.
*EDIT*
I attached the negative of the meter on the negative charge side in these shots because it was easier, the readings come out reversed polarity but it really doesn't matter for demonstration.
With a high draw voltage goes low on the cap trigger.
I have removed the cap and diode from the big system and have a test run underway. I will post back about those results but I wanted to share what I discovered about how the circuit was running with the cap in place. -----Bob
I have made a significant change to the circuit. I have removed the Cap-Diode from the trigger leg. Let me explain why I did this…
These test runs take so long to complete so I built a small single transistor circuit to try changing around while the main test is underway. I wanted to try larger caps, smaller caps and higher draw vs lower etc. I figured with a small setup I could get a feel quickly for how changes would affect the larger machine.
Here is a shot of the small circuit. The coil is glued on under the circuit board, it is 44 feet of 22AWG on trigger and power.
So this post is not about this little circuit but I have to say this thing works very well at charging up to 5AH batteries. I have been using it to charge my meter batteries and some AA’s for my telescope. Works very well!
I was changing out caps on this thing and I thought to take a voltage reading across the cap. I did this by hooking the negative to the Primary negative and the pos on the pot leg with the diode leading towards the base. I noticed that at low draw the voltage was high like around 18-22V and you could see the cap fire and recharge, but as I increase the draw the voltage would drop. After a certain threshold you no longer see the cap charging and discharging but rather just steady at a relatively low voltage. I do not know if it actually is still cycling and the meter just cannot sample fast enough or if the resistance just stays fixed at that point and no longer flip flops between the pot and cap path.
Whatever was happening I decided that it cannot be good for charging. I much prefer to see that base getting hit with higher voltage. The cap-diode works great at low draws and as a matter of fact that is how Patrick was using it when he showed it in his video. I had strayed from his method of using it when I decided to crank up the juice. I would still recommend it on smaller systems or if you use low draw. It does a wonderful job of pulse triggering as long as you don’t turn up the juice to much.
Here are some pictures on the big machine where I set the draw low and then high. I went and confirmed that the big machine was behaving the same way.
With a low draw, voltage is high on the cap trigger.
*EDIT*
I attached the negative of the meter on the negative charge side in these shots because it was easier, the readings come out reversed polarity but it really doesn't matter for demonstration.
With a high draw voltage goes low on the cap trigger.
I have removed the cap and diode from the big system and have a test run underway. I will post back about those results but I wanted to share what I discovered about how the circuit was running with the cap in place. -----Bob
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