Maybe an impossible quest, but I thought if anybody would know it would be some of the experts here. Early next year I'll be embarking on an expedition where I'll be spending a couple of weeks on one of the highest mountains in the world. I thought it might be a good opportunity to try some high altitude broadcasting with nary an obstruction anywhere in sight.
I haven't decided on what radio to take yet (right now thinking of taking one of Stretchy's Lulu transmitters, but may also take along my Yaesu FT-817 so I have some wider frequency/mode options). In whatever setup I use, I wouldn't plan on broadcasting at more than 40 watts. So here are my limitations:
- has to be lightweight and fit in to my backpack
- dipoles are out of the question. being on a mountain like where I'll be, there would be nothing to attach it to.
- has to be fairly stealthy. Yes, I'll be on a remote high altitude mountain, but so will a lot of other climbers. Since there isn't much in the way of 21st century technology to keep climbers entertained (except maybe their ipod), people still tend to pass the time by listening to AM/FM/SW radio. The last thing I want is to have one of the 300 or so climbers in basecamp (not to mention the dozen or so park service rangers) coming across my signal and then simultaneously noticing the one North Face tent with the 8' vertical propped up outside of it.
For this reason, something like a hamstick dipole probably isn't the best idea either.
With these limitations in mind, about the only thing I've found so far is this:
http://www.eham.net/data/classifieds/images/263735.jpg (the MFJ-1899T)
Seems like it would fit the bill. I could broadcast from inside the tent and run the antenna up through the vestibule zipper and nobody would probably be the wiser, especially after dark. Yes, I know from reviews that they're not known to be especially efficient, but I'll be up over 7000 meters so I think my signal should still get out fairly decent. The one problem I see is that it'll only handle 25 watts max. Maybe if people don't think I'll need anymore than that I'll stop obsessing and just take it along. The other limitation I see is that this little guy (as well as the similar "Miracle Whip" antenna) are typically said to require some random length of counterpoise to have any hope of getting a decent signal out. If it's unavoidable, it's unavoidable and I'll just have to deal with it. I just have this fear of stringing out 18' of thin copper wire and either having someone trip over it (crampons will trip you up on just about anything if you're not careful) or having someone notice it and say, "hey, what's this?" and pick it up and risk getting an RF burn.
One last alternative I've thought of would involve building my own. Take two 2' lengths of fiberglass pole with a threaded connection in the middle. Hand wind it with copper wire and cover said wire with black tape. Unscrews in the middle for easy packing. Get in to camp and screw the two ends together and I have a 4' vertical. Put a fake handle on the top and a snow basket on the end and it looks no different than the hundreds of ski poles that other climbers have propped up outside their tents. Downside is I'd certainly need to take a tuner along and it would probably still require a counterpoise of some sort. Not perfect, but maybe doable. Could probably handle far more than 25 watts too.
Any other ideas from group?