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Thanks again for the help and support. Gonna finish this mod up in a couple of days and post pictures soon.
That data sheet has no data Really, one of the crappiest data sheets I've ever seen. There's only a lower limit for the gate-source threshold voltage and no chart for the on resistance versus gate-source voltage, or any charts at all for that matter. So, hard to say, but crappy MOSFETs like that usually need at least 4V to turn on fully. There's much better "logic level" MOSFETs out there that will fully turn on with gate-source voltages as low as 2.5V.You don't need a power MOSFET either. A small signal MOSFET will work fine for that since only small currents are involved.A 100 meg resistor is really high. If the MOSFET is leaky, which I'm sure it is, the leakage can pull down the gate voltage enough to cause the transistor to start conducting. Also, with a P-Channel, you need to verify the pull-up resistor and source are in fact connected to the positive side of the switch.
nice job LearFx how hard is it to do that etching on the copper? just wondering what the brass part on the top cap is from?
Thanks fsors The etching is really the easy part. Getting the design to stick to the copper is the tricky part. It takes a lot of Patience and some trial and error to get a good image for etching. Even then the results are never perfect. It's basically the same idea as etching a circuit board but instead of a flat board you're using a round tube. The brass part on the top of the copper is a type of compression fitting used in sinks and lavatory faucets for the hot and cold water supply. I don't know what they're official named but we used to call them "Pecker Heads" when I worked as a plumber years back. I'm actually out of them and need to get more.