Thursday, November 26, 2020
Gen2 of the NY4G End Fed Half Wave
Monday, November 9, 2020
Antenna for SOTA, POTA, and DXpeditions
Initial Prototype: The initial prototype had a turns ratio of 14:2 (14 secondary and 2 primary). It used a single 100 pF capacitor across the center conductor to ground. The tests of this initial prototype after pruning for a best compromise resulted in:
2:1 SWR Bandwidth on 40 meters is 6.730 -> 7.530 MHz with a dip to 1.3:1 SWR at 7.060 MHz
2:1 SWR Bandwidth on 20 meters is 13.910 -> 14.806 MHz with a dip to 1:1 SWR at 14.360 MHz
2:1 SWR Bandwidth on 15 meters is 21.010 -> 22.070 MHz with a dip to 1.6:1 SWR at 21.610 MHz
2:1 SWR Bandwidth on 10 meters is 29.1 -> 30.8 MHz with a dip to 1.8:1 SWR at 29.900 MHz
On 10m it is not very usable unless one has an ATU.
2:1 SWR Bandwidth on 40 meters is 6.820 -> 7.510 MHz with a dip to 1.3:1 SWR at 7.150 MHz
2:1 SWR Bandwidth on 20 meters is 13.990 -> 14.840 MHz with a dip to 1:1 SWR at 14.430 MHz
2:1 SWR Bandwidth on 15 meters is 20.950 -> 22.270 MHz with a dip to 1.1:1 SWR at 21.650 MHz
2:1 SWR Bandwidth on 10 meters is 29.1 -> 30.8 MHz with a dip to 1.3:1 SWR at 29.900 MHz
Being a link dipole for 30m - here are the results for 30m:
2:1 SWR Bandwidth on 30 meters is 9.730 -> 10.880 MHz with a dip to 1.0:1 SWR at 10.280 MHz with a SWR between 1.3 and 1.2:1 from 10.100 to 10.150 MHz
A third prototype had the following results (identical in construction to the second one) with the following results.
2:1 SWR Bandwidth on 40 meters is 6.820 -> 7.500 MHz with a dip to 1.3:1 SWR at 7.150 MHz
2:1 SWR Bandwidth on 20 meters is 13.980 -> 14.850 MHz with a dip to 1:1 SWR at 14.440 MHz
2:1 SWR Bandwidth on 15 meters is 20.780 -> 22.280 MHz with a dip to 1.2:1 SWR at 21.600 MHz
2:1 SWR Bandwidth on 10 meters is 24.5 -> 29.9 MHz (which actually overlaps into 12 meters) with a dip to 1.1:1 SWR which is wide - 28.0 to 28.5 MHz so 10 meters is now perfectly usable without a tuner and so is 12m which is a very narrow band.
This is one heck of an antenna - requiring no tuner on 40m, 20m, 15m, 12m and 10m and power handling ability as follows SSB 60w, CW - 40w and Digital (key down) - 30w.
The final product: