Simplex Operation

You don't need a repeater to enjoy your 2m and 70cm radio equipment.

Communication between 2 radios tuned to the same frequency is called simplex operation.

You'll want to do a few things with regards to radio settings.
a) all radios tuned to the same frequency. typically 146.520, 146.535, 146.550.
b) all radios set to no split.
c) "Open" your squelch until static rushes through the speaker, then slowly increase it until the static just barely stops.
d) This probably isn't a big deal, but unless folks have CTCSS (PL) tone decode on, you don't need to send a PL tone.

In theory, you can talk to your friends until they are just beyond the horizon. This assumes you have plenty of power, which isn't always the case in portable equipment. So, remember the process to switch your radio to HI power when the other parties get to sounding crummy. Check in frequently so you don't get hopelessly out of range.

Height matters. If you can get up above your friends, you can be a human repeater and relay messages from one station to another. Assume there is a hill 400 ft. above the average terrain of your friends. You'll be able to talk out back and forth out to the horizon which in this case will be SQRT(height in feet) * 1.2 = miles. Or, 1.2 * 20 = 24 miles. Not bad. Bring a full battery and an aftermarket antenna like an AL-800 if you can.

http://www.eham.net/reviews/detail/3235

Some folks really take getting up high to extremes. For example, you could go "aeronautical mobile" if you could get a ride with a private pilot. OR, check out this link for an event called the Colorado 14er.
http://www.14er.org/
http://www.k0nr.com/vhfqrp.html

Lemme know what you think and I can into more detail on external antennas, portable power packs, and maybe 2m SSB operation.

73
Scott
KD5NJR