Christer said:My father used to DIY foil caps long ago. They were hardly
high-performance, though, since I think he usually used
chocolate wrapping foil. I have no idea how he knew the
capacitance of them, and he probably didn't.
Pretty simple really, if he stayed in hospital for 1 hour after zapping himself on it it would be 100uF, 2 hours for 200uF and so on
Once as a high-school project I did a few DIY caps.
I made many different constructions; however I got the highest
capacitance by rolling tinfoil around a cylinder (radius = 2 cm or so) and
separating the layers with a thin plastic film.
By putting a square signal (supply) on the cap and then fitting the discharging curve (though a knowned resistor) to a e^(t) functions I could calculated the capacitance to 462nF
The measurement/calculations should be quite accurate.
The total length of the tinfoil was 2.2meters and width was 14,75cm
I made many different constructions; however I got the highest
capacitance by rolling tinfoil around a cylinder (radius = 2 cm or so) and
separating the layers with a thin plastic film.
By putting a square signal (supply) on the cap and then fitting the discharging curve (though a knowned resistor) to a e^(t) functions I could calculated the capacitance to 462nF
The measurement/calculations should be quite accurate.
The total length of the tinfoil was 2.2meters and width was 14,75cm
first try
Adhesive aluminum-on-paper-foil with soft plastic base (that what will be removed before use)
size is 5x7 cm, dielectric paper/plastic and capacity 0.154 µF
Waiting for catalogue from teflon foil supplier.
The construction is inductive...
This could be an advantage for a non-os DAC output stage
Adhesive aluminum-on-paper-foil with soft plastic base (that what will be removed before use)
size is 5x7 cm, dielectric paper/plastic and capacity 0.154 µF
Waiting for catalogue from teflon foil supplier.
The construction is inductive...
This could be an advantage for a non-os DAC output stage
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