Topband: Inverted L improvements - Part 3 (now with data)

Todd Goins tgoins at gmail.com
Wed Jan 23 19:02:23 EST 2019


Okay, after many requests, on and off list, I disconnected the 43' T 160m
antenna at its feed point and for good measure I disconnected the coax
feedline from the system too.

It made a pretty substantial difference in the measurements. The 1.5 SWR
range is now only about 35 kHz wide but the 2.0 SWR range is still 100 kHz
which is probably still too wide.

Freq  SWR  R    X     Z
1800 1.9 31.8  -18.6 36.8
1810 1.7 32.5  -14.1 35.4
1820 1.6 33.3  -9.6  34.7
1830 1.5 33.9  -5.3  34.3
1840 1.45 34.6  -0.7  34.6
1850 1.43 35.5  3.9  35.7
1860 1.47 36.1  9.0  37.2
1870 1.6 37.0  13.9  39.5
1880 1.7 37.8  18.9  42.3
1890 1.8 38.8  24.0  45.6
1900 2 39.9  29.5  49.6
1910 2.2 41.1  34.5  53.7
1920 2.4 42.6  40.5  58.8
1940 2.8 44.7  51.4  68.1
1960 3.4 47.6  63.0  78.9

I'll test it on the air tonight (using FT-8 and the RBN) with the 43'
antenna disconnected. Perhaps it will be better? The numbers look better,
right?

Should I ground the 43' antenna instead of leaving it floating?

Thanks guys.
73,
Todd - NR7RR


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