For a simple, sturdy rig to take to the field try this fun project.
This rig was featured in QST some time ago and was designed by Wes Hayward, W7ZOI.
I built mine for 40m using five HC6 crystals that I found on Ebay.
The Micro-Mountaineer incorporates "Almost Incremental Tuning" to help dodge QRM.
Components and boards can be purchased from Kanga USA.
Wes Hayward no longer has a page at his web site dedicated to the Micro-mountaineer. Feel free to contact me, if you have any questions regarding this neat little radio.