Competition Radio Interference Solution?

[Andy Grady]

Originally Posted by STORMCENTRE

if a robot or other radio keyed up on you're mic freq you should have been knocked off the air good! not just hits here and there

The mic that i use personally is a Shure brand radio. According to the website you posted, it ranges in the low VHF range of around 152.820 MHz. I know from my work expertise in radio that alot of mobile radio frequencies operate at this range. In a large city like Atlanta, its very possible for alot of frequencies to be jumping all over each other. When you have many VHF frequencies popping up in a small band of frequencies, they tend to raise the noise floor on the VHF spectrum, particularly around the interupting frequency. Often this will cause for radios to squelch off the tones. More than likely, the problems with the microphones at the competitions has more to do with that than robot frequencies. But chances are that the robot radio's frequency range would be in a different area than that of wireless mic's or mobile radios would carry.

Also keep in mind that power of a signal can make a big difference in how a piece of audio or radio equipment squelches. Often if you have two frequencies sitting on top of each other (and they have to be directly on top to really cut something out alot) there will be massive amounts of intermodulation. Instead of the absolute cutoff like you are suggesting would happen with a robot frequency sharing a mic frequency, what you would get would be the higher power frequency winning over, with alot of interuptions, though not quite a complete cutoff. This is an effect we often run into with pager frequencys intermodding over our company radio frequencies. I find that it is very rare for two frequencies to be quite that dead on to be that destructive to a signal.

I am still curious however to find what frequency the radios run at. There are tons of radio signals that run rampid in a city...any one of them could cause an issue. Not to mention noise problems from exsisting robot radios that may have damaged parts from all the collisions robots take.

Essentially...radio control is a plecomplicated thing!