Transmitter and receiver

[jean-karim]

Hi folks,

We have an RC club at school and we are trying to undertsand the problem we have on a Radioshack rc Jeep http://support.radioshack.com/produ...ku_id=60-4300&Name=RadioShack RC Toys&Reuse=N
and as we don't have the correct transmitter so we tried diffferent TX all 49mhz as this car is a 49mhz only one TX kind of worked but the jeeps moves randomly very slowly and faster in rear motion then forward, sometimes it moves faster then other times etc... Battery is good and fully tested and charged.
My question is, would it be possible that the TX not being the exact transmitter would partially work or is it the car's mainboard???

Thanks!!

 

[barry]

The frequency of the transmitter is only part of the equation-that's just the carrier frequency. There is information encoded onto that 49MHz signal and that is specific to the transmitter and receiver used. There are many different RC encoder/decoders available, and they don't talk to each other.

 

[jean-karim]

the funny thing is that every time I have experienced a problem using the wrong TX still with either the 27.145mhz or 49.860mhz it would always either reverse steering and or forward and reverse but never with more or less power more like nothing at all or normal power. This time is the one and only time where I'm experiencing a low or no power at all and more power in reverse then forward..?? Is that still possible that it could be the wrong TX or more a defective circuit board on the car or the electric motor? Your ideas?

 

[barry]

Hard to say. One way of encoding is by simply gating the carrier on and off for a specific amount of time. For one chip that could mean forward, for another it could mean reverse.

You could open the transmitter and receiver and see what chips they are using. That's what I'd do.

 

[jean-karim]

My experience with quite a few RC Toys has showed me that high end quality Rc such as branded RadioShack, Tyco, and Nikko use their very own TX and no matter the 27 or 49mhz range and even more each car from those brands use in general its very own TX! Another experience today done on a tyco Rc truck running also on 49.860 MHZ only another Tyco TX could have it running when any other TX failed and over the two Tyco TX one them could only make the truck run for one feet distance when the other Tyco TX worked perfectly with a range of about 100 feet, both testing with the same battery, call it weird!!!