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Old 12-18-2001, 08:58 PM   #16
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The capacitor is used primarily for MOD rather than stock. A demanding MOD can distort the digital signal. A capacitor will aid in strengthening the digital signal. Performance is increased from having a cleaner signal.

I also noticed a drop in performance when using a cap for stock. Also use smaller caps in parallel (not a series) since the smaller caps will have a lower ESR.
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Last edited by RCCadet; 12-19-2001 at 04:33 AM.
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Old 12-19-2001, 12:37 AM   #17
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You propably mean in parallel rather than in series.
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Old 12-19-2001, 02:34 AM   #18
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Quote:
Originally posted by MattW
Any idea what values those caps that come with the worlds kit??
Not sure, but comparing with simmilar size caps seems to hold 4700mF (the big) and 560mF (the small ones), voltage not idea, but for temp rating, sure that is 105ºC (highest rating).
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Old 12-19-2001, 04:26 AM   #19
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Quote:
Originally posted by JesseT
You propably mean in parallel rather than in series.
You're right!

Parallel everyone!
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Old 12-19-2001, 04:30 AM   #20
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Quote:
Originally posted by Corse-R


Not sure, but comparing with simmilar size caps seems to hold 4700mF (the big) and 560mF (the small ones), voltage not idea, but for temp rating, sure that is 105ºC (highest rating).
Unless you run in an environment where the temperature is a concern, I know Spain can get HOT during its summer months, I would not be to concerned with the temp rating. I too have caps with that 100-110 temperature rating.
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Old 12-19-2001, 11:28 AM   #21
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That was my thought as well. I suspect they may be the Panasonic low impedance series.
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Old 12-19-2001, 11:56 AM   #22
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Quote:
Originally posted by RCCadet
The capacitor is used primarily for MOD rather than stock. A demanding MOD can distort the digital signal. A capacitor will aid in strengthening the digital signal. Performance is increased from having a cleaner signal.

I also noticed a drop in performance when using a cap for stock. Also use smaller caps in parallel (not a series) since the smaller caps will have a lower ESR.
Signal? What signal are your referring to? Radio signal? If so, then why would the cap be soldered onto the battery wires and not the motor wires? A capacitor is used to buffer electrical current so that there are no voltage dips. These capacitors have been used in a larger scale in mobile audio for a long, long time. Capacitors buffer current so when voltage requirements become severe (like when heavy bass is being played, or full throttle from a dead stop) no dip in voltage occurs. Many people have stated that there is no effect, positive or negative, in Stock racing. However, I've found that my Quantum Competition runs much better with it on.
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Old 12-19-2001, 12:38 PM   #23
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Rog: You solder to the battery wires. You have it right, a MOD is a demanding motor causing dips, therefore, you use caps. Not as much power is stored as thought to be, just enough to keep the signal strong.

As for the audio applications, the caps are a temporary storage for when the demand is to great for the amp and so it unloads giving the monster magnets what it needs to produce the sub-sonic sounds, sounds often felt and not heard.

I have not run across a situation where a stock motor warrants the use of a cap. I actually suffered in performance. It was very noticeable out of the turns. Once I removed the cap the burst out of the turns was very noticeable. It doesn't make since really but that is what I have experienced.
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Old 12-20-2001, 07:45 AM   #24
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what does a schottky diode do?...is it the same as a capacitor?
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Old 12-20-2001, 08:19 AM   #25
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Quote:
Originally posted by Dragon
what does a schottky diode do?...is it the same as a capacitor?
Nope, schottky and receiver cap works on the same direction but using different methods.

Schottky diodes works in the motor supressing the back off spikes caused by releasing the throttle stick and not using the brake (in this moments the motor acts as an alternator who is shorted by the act of installing the diode) producing high power spikes to the ESC.

Receiver cap works stabilizing the 5 volts supply from the esc and eliminating those high frequency ripples 'caused' by the use of high frequency ESC's.

In 'ye old days' the use of capacitors in the receiver was for eliminating glitches caused by the use of very low turn motors who cause a lower supply of energy to the receiver, acting as a little reservoir to cope with this transient situation.
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Old 12-20-2001, 09:10 AM   #26
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No, I don't think so. When you release the stick and you're using your motor as an alternator, the voltage it creates is still positive, but the shottky only lets reverse voltage through.
On the other hand, the speedo feeds current in pulse mode to the motor, which is inductive load. On every pulse, when the current is switched off, the motor creates a negative voltage spike that is absorbed by the shottky diode. Please correct me if I'm wrong...
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Old 12-20-2001, 09:48 AM   #27
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I have had my QComp. for several months now. Have seen others (QComp.) come and go. I guess there really are a few bad apples in every bunch. Tried the big Cap thing, but didn't really notice any difference in ESC temp. so I added a heatsink to it and haven't had one problem. The best ESC I have used to date. Still have a NOVAKtc2 in the box just in case though.

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Old 12-21-2001, 11:58 AM   #28
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Quote:
Originally posted by Corse-R


Nope, schottky and receiver cap works on the same direction but using different methods.

Schottky diodes works in the motor supressing the back off spikes caused by releasing the throttle stick and not using the brake (in this moments the motor acts as an alternator who is shorted by the act of installing the diode) producing high power spikes to the ESC.

Receiver cap works stabilizing the 5 volts supply from the esc and eliminating those high frequency ripples 'caused' by the use of high frequency ESC's.

In 'ye old days' the use of capacitors in the receiver was for eliminating glitches caused by the use of very low turn motors who cause a lower supply of energy to the receiver, acting as a little reservoir to cope with this transient situation.
so in simple english u mean it protects the ESC?
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Old 12-21-2001, 12:34 PM   #29
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Quote:
Originally posted by Dragon
So in simple english u mean it protects the ESC?
Yes. In fact, I did a test with an old Tekin ESC700 (a very, very old ESC). I've fried several times the brake FET's, and since I've installed a schottky in the motor, I never fried the brakes.
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