On 9/28/07, Porkchop <[EMAIL PROTECTED]> wrote:
>
> From my armchair...
> An RC helicopter I imagine is a good use case for a high-powered remote
> control. You probally have very good range on that transmitter?


Yea, they say not to go above 400 feet in the air when you are within 3
miles of an airport, so I guess it's got some range on it.

Your coax cable running across the floor can easily act as a big antenna.
> Its possible that the metal braided shield isn't grounded, so doing that may
> help (or do nothing at all). 72mhz (sure thats not 172mhz?) is a far cry
> from 1ghz, but all it has to do is confuse the signal a little before the
> digital tuner can't differiante the 1s from the 0s anymore...


Checking the manufacturer's website I see they have crystals for this set
that range from 72.130 to 72.870, if I remember the color on mine correctly
it's the 72.170 set.  But definitely not 172.

Now as to the top-half-of-the-room... Does the 'copter have any
> transmissions sent back to the remote? An "out of signal range" light or any
> other feedback? It may not be active unless the remote is powered on. The
> proximity of the helicopters transmitter to the cable you're running along
> the floor...


The crystals are labeled Tx and Rx, but I'm not sure if that means they only
use them for one-way or  they are labeled as such because this clearly
differentiates which should go in the transmitter and which should go in the
helicopter.  I can try to find out if there is two-way going on.

Another thought just occurred to me.  This thing is powered by two
reasonably strong electric motors.  Those should produce some pretty strong
EMF when they're revving.  When the helicopter can't see the remote it's
supposed to disarm the motors; would they do that if they were connected but
not spinning?  Seems to me my physics classes say that you need current
flowing to generate EMF and I doubt that a powered but stopped motor would
draw that much juice.

-Jay
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