Does anyone have any suggestions regarding swimming laps and still maintaining signal between the sensor and receiver ? I went to the pool yesterday, I have the sensor positioned on my stomach. The pool is 25 yards long so 75 feet from end to end. I put the receiver on the side of the pool in a ziploc bag about midway between the two ends. I figured while the sensor would be out of range for the last 35 feet it should be in range for the middle 40 feet of the pool. I swam the back stroke for an hour so the sensor was not too far under the water. Almost from the very beginning of the swim I got the "Out of Range" notice and this continued throughout the hour I was in the pool. Having read the User's guide I understand that wireless communication does not work well in the water and the range is less but I am disappointed that communication ceased almost immediately as I got in the water. It resumed within 5 minutes of getting out of the pool and has been fine ever since, but I enjoy swimming for exercise and I would love to hear if anyone has had success. I don't know if the fact it is an indoor pool has any bearing on this, but I did not have this problem when I swam outdoors in a pool a lot bigger than this one.
It won't travel through water. It's the same reason you can't get recorded data off of a garmin HR monitor, etc. The RF (or ANT+ or bluetooth, etc) can't communicate through water as a media the way it can w/ air.
I second Bradford's reply - RF just won't travel through water at all, water attenuates the signal so much that I think trying to get any readings at all back to your Dex receiver is going to be almost impossible.
Have you considered using the waterproof cases that are designed for cell phones, and have your G4 with you instead of the sidelines ?
I think the transmitter and receiver are not in constant communication, but only for the few seconds once every 5 minutes when it gets the reading. So that means only 12 attempts in 1 hour. You probably also spend slightly more time at each end doing turns, which is where it is definitely out of range ? But I agree, seems like at least 1 out of 12 would have been in range.