Variable ROF.

[MPhantom]

I'm into High Voltage and general electronics. I just finished build my 600v 1,600uF capacitor bank for blowing things up. And what got me thinking was I've read a small webpage on replacing batteries with capacitors, if you use15v capacitors, you could also buy a variable voltage (they're very cheep, I have a 0-50v one I made and supplies up to 10amps) transformer and charge the capacitor to the voltage you want, but the charger/variable transformer must be smoothed and filtered to keep the voltage constant. Just a thought maybe you would like a little more ROF today? or a little less if you want to save on BB's.

[UnionJack87]

Re: Variable ROF.

The only problem I can see. (and I am not an electronics engineer by any stretch of the imagination) is that most motors demand 25amps-35amps peak load in bursts. And u say this system can only supply 10amps. Result? Gearbox wouldn't even turn over.

[bigshep]

Re: Variable ROF.

It would be a lot simpler to put a variable resistor in line rather then trying to use a bank of caps.

[MPhantom]

Re: Variable ROF.

The only problem I can see. (and I am not an electronics engineer by any stretch of the imagination) is that most motors demand 25amps-35amps peak load in bursts. And u say this system can only supply 10amps. Result? Gearbox wouldn't even turn over.

No the 10a PSU is just to charge the capacitors like you would a battery.

What I was thinking, say one day for some reason you only want 8.4v then charge the cap bank with only 8.4volts, if you would like 9.6 or even 11v then charge the bank up with something (variable power supply) to the desired voltage.

I also don't see why people buy mini tamiya to large and vice versa, it's still the same voltage so there connectors does nothing. You could simply use two wires.

[BioSniper]

Re: Variable ROF.

If you are looking to vary RPS (I looked into this some time ago and it was a little beyond my manufacture skills) you really need to use a PWM circuit from what I've seen.
Variable resistors that will handle the 20-40A that a motor draws will just burn out or need to be so massive that it's just not practical.
I do have a "burst wizard" that does RPS varying which I purchased out of curiosity, but it's a bit rubbish to be honest as expected.

I'd be interested to see if someone can some up with a cheap and simple to build strip board or similar, PWM mosfet.

Obviously existing products such as the SW-Computer can do this, but they are a little expensive for my taste.

[bobfish]

Re: Variable ROF.

again im no engineer but i know there is a delay when charging the capacitors, which would mean that you would have a maximum rate of fire that you can achieve i know it depends largely on the EMF of the battery but surely it would still be a quicker ROF if you use the standard setup they have now? rather than waiting for a capacitor to charge ... also gives problems with trigger response as you have to wait for the capacitors to charge after pulling the trigger.
unless you have the capacitors in front of the trigger, so they are continually charging, that would probably increase trigger response ... but on full auto they would still discharge and then your ROF would be seriously impaired especially for long bursts of fire

oh and funfact my ICS mp5 has a 13 amp fuse ... so I don't know what these people are talking about 20 - 25 amp peak currents

[Coz]

Re: Variable ROF.

Would it not just be easier getting one of them Tiny rheostats like they use in the A&K M60 series?

[cannon_fodder]

Re: Variable ROF.

or copy the electronic speed controller from a variable speed battery drill

[mike-f]

Re: Variable ROF.

Although you can change the speed with the voltage it's not ideal, lowering the voltage also reduces the torque. You need to use a PWM controller(fet control).What you really need is programble rof/ fps gearbox like mine!

http://www.youtube.com/watch?v=wfuBV...e_gdata_player