Topband: HiZ 4-8 and beverages

Ignacy Misztal no9e at arrl.net
Tue Nov 21 11:08:38 EST 2023


Lee helped me troubleshoot the HiZ issues.  Here is what turned out to be.

I compared 800 ft beverages with the HiZ. The beverages have a DXE preamp.
I use Flex 6600 and the beverages work best with 8 db ANT gain in the Flex.
On 160m, HiZ works best with 24 db gain in the Flex.

When ANT gain in Flex is set lower, the internal circuitry increases
the internal gain for more-less the same white noise level. So when
listening, you never know whether the band is noisy or the ANT gain is low.

A few months ago, a new firmware in Flex introduced a bug - when the
antenna is changed, the gain is reset to 0.
So when I was A/B beverages and HiZ, the gain was resetting to 0 and HiZ
appeared noisy. Now, when I change the gain of Hi-Z to 24 db, Hi-Z hears
DX, just a tad noisier than 800 ft beverages.

Another problem was a bad cable connecting the radio and Bias T feeding
the Hi-Z. It allowed for some PS noise ingress.

Few morals here. First, this group is useful, and Lee knows his stuff.
Second, if you need dramas and want to spend hours away from
work/wife/children, buy a Flex.

Ignacy NO9E


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