noob question

[Jirimar]

why do you have to solder caps to the leads of some motors?? what does it do, and what happens if you don't use them?? :confused:

[Hoghappy]

Welcome to a really good forum and a nice bunch of folks.

The capacitors can help reduce high frequency noise/interference from the electric motor that the radio reciever can pick up causing your servos to glitch. Now the interesting thing about this is just last night I was told the radios on the market now...don't need no stinking capacitors.....anyone else heard that? :eek:

Capt. Crash

Maybe it's just a brushless thing?

[lowdive]

the current 2.4GHz receivers are much better at blocking out motor noise. in some cases it's still good to add caps. to eliminate any chance of this. brushless, afaik, is less prone to this compared to brushed motors.

[patmat2350]

In the early days of "radio" (wireless, actually...) the signal was broadband and created by literally making a spark... it was good enough for Morse code.
And guess what happens in brushed motors where the brushes skip from one commutator segment to another? Sparks. Just look in the little window of a running motor.

Now, AM radios are much more sensitive to electrical noise than FM (remember driving under powerlines with an AM car radio?), and digitally-coded signals using FM (that would be PCM and the new 2.4 GHz radios) are even better at rejecting the noise. Perfect? I dunno... but it's easy to solder those caps on, which BTW also reduces the noise background for others running their old AM sets.

The capacitors are like little electricity sponges which absorb surges during commutation, thus decreasing the tendency to spark.

PM