The front battery had gone flat during a prolonged gap in lockdown so decided to replace BOTH as, for £100… it’s not worth the hassle of them going down on you when you least expect it ..
Front was done a few weeks ago … rear needs either a bigger opening or cut open again …
Having cut on a joint … it was still a bit of a fiddle to get the battery bolts to pick up … classic short bolts .. and, if you pop another ring on … then it becomes an art to push a flat screwdriver under the nut … and lift it just enough to help the thread bite ..
I have a direct negative feed from the Trig radio … which I had forgotten about … and also have a charger adaptor wired so it’s easier to just pop the access plate off and put it on charge.
I’d forgotten the direct earth lead that Trig recommend …. just wondering if this could be that niggly noise on the radio … let’s see at next engine run 😊
UPDATE … yes … it was … the original earth from Trig unit all the way to the rear battery negative post …had a bad (single) crimp .. so allowed movement .. recrimped and next flight really clear … just need to sort wind noise,squelch for optimum pilot, pax chat now
Oratex is just awesome … cut on the joint … glued overlap edges .. and got the pinking shears out after 4 years of not using them .. then heat gun and iron to tighten it back up
… and yes … i did clear out all the dead flies and cobwebs before I sealed her back up for another 4 years
Jersey Sherwood Ranger 
I’m watching your posts and learning a bit about the Ranger .. do you have the aft battery for CG reasons? If so, are there other corrective measures that perhaps have already been addressed in the design?
Yes .. i had ‘dead’ weight in the back and the LAA suggested a rear battery … popped it there and ALL lead removed to produce spot on balance .. left the front battery in as the drain over 4m+ of cable was quite large .. 2 in parallel.. not missed a beat and starts brilliantly