On January 4, 2007 at 22:16, learninght said...
You could indeed put all 4 in the terminal block but because
of the inch or so of distance, it is unlikely the .1uf
would have much effect. On the terminal block, I'd just
do a 100, 10 and 1 uf.
The voltage of the cap must be > peak voltage applied
to it in any circumstance. In design, that value is usually
doubled for extra margin. Since the MRX-250 expects a
5V input, the 6.3V should work but doesn't leave much
margin. On the other hand, the worst that will happen
is the capacitor will fail. A 10V cap is probably best.
You can use a 25V or even 50V capacitor but these do get
physically bigger as the voltage grows.
In other wrds, if you have one on hand, there's no harm
in trying a 6.3V. If you are buying one, try for a 10V
or 25V.
Any cap of this capacitance will probably be an electrolytic.
Make sure and attach the + side to the 5V screw and the
negative side to the ground screw.
How long is your cable run? What are your failure symptoms?
I'm confused why you would need more than one capacitor. I'm no electronics engineer but I did study electronics in college. I still have one of my textbooks from 1964 (yes you probably can figure out my age now) and I looked up the equation for using capacitors in parallel. And yes my memory was correct, the total capacitance is equal to the sum of the individual capacitances.
CT = C1 + C2 + C3 .......
So effectively 100uF, a 10uF, a 1uF and a .1uF would give you 111.1uF total capacitance.
Why wouldn't using just one 100uF capacitor be roughly the same?
