Upper section anomoly
Just be extra careful, especially when you've got it fully extended.
Old thread, but it still fits the anomoly I found with a brand-new version (2010) and an older one about 10 years old that had rolled under the frig.
I was doing some weak-signal VHF work with the antenna sections fully extended - which for me means pulling out the sections from the center loading coil until it reaches a physical stop, and then usually trimming the sections back down starting from the top.
What I found was a very abrupt improvement in signal strength in regards to the very first element to come out of the top of the coil by merely pushing it back down into the coil by a mere fingernail-width! This happens on both my old and new version!
I thought that this abrupt improvement was due to some bad wiper or something else making nothing but a capacitive contact inside - but when tested with a voltmeter, I had continuity between the top and bottom of the coil.
The only way for me to describe this is something similar to turning a tuning-slug too far out of a coil and the circuit goes practically dead, and then springs to life like it should with only a minor adjustment.
You won't notice this affect on strong signals, so you can check for yourself on VHF by using an attenuator and if you have an s-meter you can see an abrupt improvement on the very weak signals. Not a full-scale improvement, but something much faster than you could with the usual fine-tuning of sliding the elements.
Seems like pushing the very first telescopic upper section back down just a slight amount, makes it perform better for those bands that use the upper elements. I don't know what's inside that coil, but if it is truly a coil, I recommend not pulling that top telescopic all the way out to the physical stop. Push it back in 1/16 inch or so.
