Antenna problems.

Hi, I accidently cut my atenna but reattached it. It’s giving me major range issues, however, it was doing this before I cut it. Any reason why? (The batteries are full on the transmitter and receiver)

No one knows if cutting an antenna and reattaching it cuts down on range?

How did you re-attache it??

How long was the Antenna, before it was Cut??

Antennas work best when they are the correct length. The Vexplorer is using (IIRC) 27Mhz Radio Frequency, so the Antenna will need to be close to a division of ~11 Meters, which is the Full Wave Length of 27Mhz.

See link 27 Mhz cable length, for marginally related reference.

Hey, it’s you again :slight_smile:

It is roughly 10 inches long, and I simply reattached it by stripping the wire ends where it was cut, removing the white stringy substance in the middle, and only attaching the copper.

The thing is, when I first got this vexplorer I had some range issues and I basically took an antenna off of a TV and attached it to the vexplorer next to the antenna (I put the antenna in its plastic tube and taped it to the TV antenna) – it felt like this gave me more range, however, I recall turning it on one day and the range was crap and I thought it was an antenna problem.

So far, I have been tinkering with ways to make the range better, and my last idea no longer works, but rather, makes it worse. From what I’ve observed, the vexplorer antenna when directly in contact with the TV antenna loses its range. Now knowing this the range issues have gotten a little better since I have gotten rid of the TV antenna, however, I still don’t have ideal range and have no clue how to increase it.

I’m a little confused when you say that the antenna needs to be 11 meters. Wouldn’t that mean I would need something around 440 inches or about 36 feet? Seems kinda weird to me.

Yes, it me!! (See Some questions…, for a previous dialog)

Did you Solder the Copper Wire together?? Oxygen can combined with the Copper (Oxidation) and inhibit the flow of Electrons in the Copper Wire.

The Batteries in the Transmitter are New?? Do you know someone with another Vexplorer, that you could try their Transmitter with your Receiver, and vice-versa.

Off Hand, I would guess that the TV Antenna is Canceling Out the Signal from the Transmitter. There should be a length of Antenna that will help the Receiver, rather than Hinder it.

My Radio Knowdege is rusty… The following should be close…

The FULL WAVE of 27Mhz, is ~11 Meters. The antennas can be Half that length (1/2 Wave) or a Quarter that length (1/4 Wave). Also there can be a Coil in the Receiver, that the Antenna is connected to, to increase the inductive reactance of the Antenna. This is called Base Loaded.

See the Discussion - receiver antenna length? thread.

Nope, never soldered it. It works okay now but I will figure out how to get it the right length, etc in the future.

Since you’re here I might as well ask you a question that has also been on my mind… Is a wireless switch I can buy? Essentially, I have a little 9V camera attached to my vex and I have to turn it on manually but would really like to somehow do it wirelessly (without getting a fancy controller, prefrably a controller that comes with the switch)… Thanks much!

I haven’t tried this but you could hook a transistor up to the vexplorer receiver and use that to control the power to the camera from the regular remote.