418 Mhz or 900 hz?
418 Mhz or 900 hz?
(OP)
We're working on adding an RF control to our winches. Our winches use a high speed commutating motor that emits a fair amount of RF noise. I'm not pleased with the range we're getting with the 418 Mhz RF modules. Without the motor running the range is much better. I'm thinking the motor probably would emit less noise at 900 Mhz and I might get better results with the 900 Mhz modules. Any opinions?
Also, running indoors, the reflections produce too many dead spot locations in our plant. Would the 900 Mhz produce less reflections from the concrete block and steel beams typical of an indoor industrial building?
Also, running indoors, the reflections produce too many dead spot locations in our plant. Would the 900 Mhz produce less reflections from the concrete block and steel beams typical of an indoor industrial building?
RE: 418 Mhz or 900 hz?
When this is done, you will surely have a better range. And is possible that this increased range will reduce the blind spots.
Are the motors DC low voltage motors? Is there any PWM inverter involved?
RE: 418 Mhz or 900 hz?
RE: 418 Mhz or 900 hz?
I think that you should try ferrite cores in the motor leads. And also a capacitor across the brushes. You may need to talk to someone that knows about EMC and filtering to arrive at a good solution.
RE: 418 Mhz or 900 hz?
You will find though, that the interference at 900MHz is less than 418MHz, but that's not the issue. There should not be that much at 418MHz.
RE: 418 Mhz or 900 hz?
A module in 915 MHz ISM band will have some reductions in dead spots due to the shorter wavelength and the possibility that your module will not be completely within a null spot. Additionally, many modules at this frequency are Frequency Hopping reducing the size of potential null spots. You can also select a receiver with antenna diversity (two antennas spaced slightly apart) - very effective at eliminating null spots.
RE: 418 Mhz or 900 hz?