i just bought a r-4 and wallfarts battery..
i can't seem to get the extrenal bettery to work do i need to rig this thing?
The R-4, like the UA-5, has reversed polarity relative to most units and most batteries. Most units require, and most batteries and cables provide, (+) tip and (-) ring, whereas the R-4 and U5 take (-) tip and (+) ring.