I have a rather odd problem with a J-Pole "copper cactus" antenna that I
just installed this evening. I can transmit and hit local repeaters w/o
any problems w/ an HT on LOW power ( 1.5W) but can't bring up even the
closest repeater on HIGH power (4.5W).

The SWR for the antenna is 1.1:1 to 1.3:1 across the entire 2m band
(direct antenna reading - not w/ the transmitter in the loop) and I've
got a 5-coil balun right at the feedpoint to trap any return RF.

Any suggestions? It wasn't my intention to build a QRP rig....

Perplexedly,
Scott Drumm
N3XFD