Planed new EME antenna for 70 cm
Building new 24 el 70 cm ant for V-pol
About me SM4GGC
Hamradio station
EME slide show
QTC EME 23cm

New project for EME Antenna for 70 cm
My plan for 70 cm in the spring 2025 is to put up 2 more YU1CF 26 el yagis for H-pol and try to make 4 24 el yagis for V-pol.
I imagine a configuration like the one in the image beside that will give a favorable radiation pattern for H-pole with strongly suppressed side lobes according to antenna modeling with EZNEC.
More will follow later
H-pol EL radiation pattern. Gain 26,97 dBi. Front/Sidelobe 15,26 dB
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H-pol AZ radiation pattern. Gain 26,97 dBi. Front/Sidelobe 20,82 dB

Building 24 el 70 cm antennas on 6,3 m boom for use in a 4X24 el configuration
The model for the antennas is taken from YU7EF 24 el with 6 mm element diameter in free space.
First did I have to recalculate the length for all elements to 8 mm diameters see simulations made with EZNEC for 8 mm elements and 12 mm dipole



Dismantling 4 old 2 m antennas to use booms, element holders and elements for the 70 cm antennas.
I did first build a smaller antenna to try out the approximate boom correction for this type of element holders with the element placed about 9,5 mm above the 35 mm diameter boom.




VNA measurements on first try out with 16 mm boom correction and the final result with 13 mm boom correction
16 mm element boomcorrection


16
13 mm element boomcorrection

About me SM4GGC
Born in 1953 and has worked with mobile communications and telecommunications since 1973. I was interested in ham radio early when I was 14-15 years old together with my younger brother SM6FGN. My brother learned CW rely fast so he did get his license for ham radio at 16 years age but I struggled some more years with CW before I could pass the test for ham radio.
In the mean time was I building radio equipment transmitters, receivers and antennas that my brother could operate from our parents house. First years was it for HF but just when I was ready to pass my license for ham radio did I discover VHF 2 M and the thrill to make long distance QSO via tropo and aurora
When I got licensed 1973 was the plan to build a station at my parent’s summer house located at JO69XB with good take off and free horizon over lake Varnern perfect for VHF. At this time was there no electricity at the house so a gasoline generator was the solution. Antennas for 2 M was growing from 2x13 el, 4x12 el and to a 8 times 12 el NBS homemade yagis. I was active with MS and EME on 2 M until 1983.
There was a long time of QRT between 1983 to 2011. Since May 2011 are I on the air again and not surprised that many of the guys from 70-80'ts still is there. The thrill and excitement is still living for ham radio. The video to the right is recorded 2013 by TV4 in sweden





My QTH is now about 8 Km north of Karlstad centrums on a little hill called Skare mountain 75 M ASL (not much to montain hi hi). Well I have a some god take of to the south as lake Varnern is there within 10 Km.
I am using a Kenwood TS-2000 as main transceiver that are modified with separate RX antenna connections. To get it stability on frequency the fan also can be sett to constant speed.
SDR-play RSPdx is used to spectrum viewing, Qmap and map65 on 144 and 432 MHz with the excellent software SDR Console Version 3.1
On 18 m Versatower antennas for 2m and 70cm
2m: 4x12 el. Pa italab1000 with about 800W at the antennas
70cm 4x26 el YU1CF, Preamp Khune MKU LNA 432A PA Italab palett in shack with about 400W at the antennas
Hamradio station

