At a summer QTH I have an 80-10 EFHW antenna (about 135' length horizontal, about 25' AGL), attached to a 50 foot RG8X feedline. I also attached a short (15-20 foot) counterpoise wire at the junction box containing the matching transformer, where the coax meets the antenna wire....to provide some future flexibility, should I decide to insert a common mode choke somewhere along the feedline. Paired with an ICOM 7300 I have no problem tuning on every major band, and with limited use it seems fine for my simple needs. However, measuring the resonance point dips with a nanoVNA analyzer I noticed that the frequencies are on the low side - suggesting that I may eventually want to trim the line length.... Band Frequency of lowest SWR 80m 3.46 MHz 40m 6.78 MHz 20m 13.88 MHz 15m 24.3 MHz 10m 27.75 MHz Anyone care to do suggest how much length I could trim the the wire by to bring me closer to the band centers? And can I shorten the length by simply doubling it up at the end rather than physically cutting it?