As most of you know I'm installing a G5RV in an inverted V configuration at approximately 35' AGL. I will be feeding the G5RV with RG-8X coax. I also have a MFJ-915 RF isolator "balun" that I plan to use at the feedpoint of the G5RV ladder line. This MFJ-915 isolator is constructed of a 13" length of RG-303 with 50 ferrite beads on it, all encased in a PVC enclosure. I've been reading that at high SWR levels (which the G5RV is famous for on all bands but 20M) can cause heating of the 1:1 RF isolator. Unadilla's website also advises of this with their model of the 1:1 isolator, however they also state that many hams seem to not care and do it anyway. I do plan to utilize the MFJ 1:1 isolator in my installation, however, I'm curious about whether it would be wise to do any/none of the following in the name of RF supression.. 1. Construct a quick 1:1 coax balun (a few wraps of excess coax around a 6" former) immediately following the MFJ 1:1 isolator? (Transceiver - coax - 1:1 coax balun - MFJ isolator - G5RV feedpoint) 2. Simply cut off unneeded coax, feed the MFJ 1:1 isolator normally and connect the G5RV feedpoint? 3. Construct a quick 1:1 coax balun at the G5RV feedpoint, and place the MFJ 1:1 isolator INSIDE at the connection to the transceiver? (Tranceiver - MFJ isolator - coax - 1:1 coax balun - G5RV feedpoint) 4. Simply cut off uneeded coax, feed the G5RV directly to the feedpoint, and install the MFJ isolator inside at the connection to the transceiver? (Transceiver - MFJ isolator - coax - G5RV feedpoint) I'm sure there's lots of reactance/inductance variables at play here. I just want to do what's best for performance and RFI common-mode supression. Also, let's please not get into a politically correct discussion about what a balun really is vs a choke. Tomato, Potato, whatever. You guys know what I'm talking about here.