I would take a look at Bonnie's links earlier in this thread. She has a grasp on what is working in the cave/mine environment...the challenge with the low frequency bands (40M, 80M or lower) for portable or mobile use is antenna efficiency. It's tough to make a portable antenna that can be lugged through caves...but if you put in 20 watts and radiate 2 or 3, that may be enough. I'm out of my depth...so consider using Bonnie's knowledge base and let us know how things work out. One of her quotes: In caves, I found that 2 watts at 7 MHz or 3.9 MHz SSB, with small whip antennas, will go through about a quarter mile to a half-mile of solid rock. Further if one station uses a longer antenna.
Just got back from a four day trip. Thanks for the info. Yes, I agree. There's a lot of loss in power, but a fews watts is perhaps all we need for a solution. We'll be looking at making this work this year.
We're going back to reward mine this year on May 20th. We will keep you all posted as to what our transmission testing results will be.
We did not have enough of the right gear and antennas to make this happen. We will make another attempt next year with lower frequency gear.
Some of our videos seem to be controversial for some commentors. I guess we have only been showing the unusualy things. Here's an update and an overview. Yes, we do normal things like HF, VHF, APRS, MESH NETWORK, and soon some CW.
