Again some antenna measurements. This time, the new 12 elements 3WL LFA yagi for 144MHz. The second one is a more than 20 years old Kathrein 728888. The third one is my homemade 1WL broadband FM yagi for 88-108MHz.
1. 12 elements 3WL LFA yagi for 144MHz The SWR sweep between 142.7 and 145.9MHz. I am not impressed. The antenna is too low in the band. This antenna is not homemade but a commercial type. The antenna is also very sensitive for other conductive material near the dipole. SWR on 144.300MHz is 1.34 which is acceptable but can be better. So room for improvement. Good news!
ERRATUM! Changing 2 elements (swap element 10 and 11) improved the SWR! I didn’t read the manual (shame…) so this mistake was made easily. Thanks to Eric PA3CEV for his help. SWR is now below 1:1.1 on 144.300 but resonance is still outside the 2mtr band, at 143MHz
2. Kathrein 728888 broadband vertical. This antenna is specified from 406 and 430MHz and is 2016mm long. SWR should be below 1.5 Sweep between 379 and 481MHz. Almost below 1:2 in the whole range. Wow! This is what I call broadband. Much better than the Comet and Diamond antennas I’ve used in the past. Even useable between 340 and 530MHz as receive antenna. Good job Kathrein Engineers! SWR between 405 and 455MHz. As the specs promised SWR is <1.5 from 406 and 430MHz.
3. Homemade FM yagi (length is only 1WL) Sweep between 73 and 123MHz. SWR sweep between 85 and 111MHz. The SWR is <1.6 in the whole FM band (87.5 and 108MHz)
July 5th, 2014
The cheap but well known discone scanner antenna Diamond D130N was measured and I was surprised. Good SWR between 120 and 520MHz. Above 520 I cannot perform such SWR sweep.
April 3th, 2014
Today I did some measurements to compare the Diamond D777 with the Comet GP98. The Diamond D777 is a receive only antenna for aircraft enthusiasts and the Comet GP98 is a triband antenna for ham radio bands: 2mtr, 70cm and 23cm. First, the data of the Diamond D777:
The temporary setup with the Diamond D777 at 8mtr above ground. The Comet GP98 was on the same place and same feeders. SWR plot between 118 and 182MHz SWR plot between 104 and 136MHz SWR plot between 115 and 131MHz SWR plot between 143 and 147MHz SWR plot between 268 and 332 MHz SWR plot between 284 and 316MHz SWR plot between 427 and 443MHz Local ATIS receive S9+10
And now the Comet GP98 antenna. The Comet G98 on it’s test location. SWR plot from 118 and 182MHz SWR plot from 143 and 147MHz SWR plot from 418 and 482MHz SWR plot between 427 and 443MHz SWR plot between 117 and 133MHz SWR plot between 284 and 316MHz Local ATIS receive S9+10
April 2th, 2014
Here some SWR measurement plots of the HyEndFed 3bander (40/20/10meter) SWR plot between 0 and 31MHz SWR plot between 6975 and 7225KHz SWR plot between 13950kHz and 14450kHz SWR plot between 28 and 30MHz SWR plot between 27 and 31MHz
And also a measurement of my homebrewed Korner FM yagi. See also FM-DX section. SWR plot between 87.2 and 112.8MHz
The antenna is now at another position on the house. The local ATIS at 126.025MHz is now much stronger: S9+20dB on the Icom R7100
