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WB4APR
01-03-2012, 23:09
Ham radio walkie talkies are great for maintaining contact among scattered hikers and by SAR teams. Radios with GPS can be tracked and seen live on http://aprs.fi either by knowing their callsign, or just zooming into an area.

This Spring, hope to consider getting a number of Hams to section hike and develop a coverage map for those that follow. I'm wondering if there are any others interestred in participating? Also on July 23rd each year for 4 hours we try to communicate from Springer to Katahdin using 14 hikers on top of 14 mountains covering the entire 2170 miles. See http://aprs.org/at-golden-packet.html

Apology: We do use earphones so as to not bother anyone else. Sorry, its just that altitude gives range, and that's what we like to do. P.S. always works and is not dependent on cell phone networks. Bob, WB4APR

k2basecamp
01-03-2012, 23:29
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rocketsocks
01-04-2012, 09:20
I've done this at my home,long wire,1 germanium diode,galena(secondary lead mineral)and a earphone...did'nt work that well?what was I missing,would love to try this again.

Slo-go'en
01-04-2012, 12:44
I've done this at my home,long wire,1 germanium diode,galena(secondary lead mineral)and a earphone...did'nt work that well?what was I missing,would love to try this again.

It's a little more complicated then that. You need to tune the input, which is done by winding a coil of wire and using a variable capacitor. If you use a germanium diode, you don't need the galena. Also, you need high impedance headphones, which are not very common today. The type used with MP3 players and the like will not work, as they are low impedance.

Google "crystal radio sets" and I'm sure you will find many plans for building these simple radios. I made my first one when I was like 8.

rocketsocks
01-09-2012, 18:52
Cool,thanks I was following a scematic on the back of a bar napkin

Wise Old Owl
01-09-2012, 20:48
Bob - I am stumped (n2gwd) I love hill topping but I have given up on all this for smart phones.