Satgen 130 Ground Station Aerials by GM4IHJ 22nd Sept 91 A very popular question in recent weeks has been " What aerials do you use for satellite XYZ ". 21MHz up , I had an indoor dipole in the loft. I recently removed it and have not yet decided on a replacement. 29MHz down . I have a crossed yagi made from an old TV X aerial extended to cover 10m. It is mounted horizontally above the Chimney. Recently however a new computer game has come to live next door, and when its owner comes home from school, I lose 29MHz reception. The solution has been to refit the sloping 10m dipole coming down from the chimney at the other end of the house away from the QRM. This dipole has a pre amp mounted at the dipole and it works well even on RS12 sub horizon despite my small neighbours activities. I still need to keep my own shack quiet to reach this level. This has always entailed taking off my Epson LQ550 printer and suppressing my TNCs , and using quiet IBM micros. 144MHz up and down. Here it is horses for courses. Mir suffers a lot of Faraday polarisation rotation so I have a 5XY yagi rotatable in Azimuth above the chimney. I can switch from X to Y feeds as necessary to chase the polarisation. This works well on the RM-1 downlink. I am only interested in DX and DX occurs at low elevation so it does'nt need an elevation rotator. I fitted a pre amp for when AO13 is on my horizon but I do not need it for RM-1 downlink. In the backyard I have a minitower with another 5 element 2m yagi mounted for vertical polarisation with AZ and El rotation which I use on the Pacsats and , mode J Fuji and AO13. I used to, use a 10 XY yagi on this mast for AO13 but I got disgusted with its mode B and gave it up. 435MHz up and down. For DX at low elevation I have a 21 element long yagi on the chimney . This has AZ rotation only and is very good for mode J Fuji and AO13 mode J and mode S as well as the Pacsats and Uosat 3 and 5. When the sats are at higher elevation I use a 48 element multibeam on the backyard minitower. This has Az and El rotation . I find the 48 element to be a very compact useful aerial and I have discarded the 4 by 10xy yagis I formerly used for AO13. I particularly like the 48 element when AO13 is at high elevation on mode S. 1269MHz. I no longer have any aerials for mode L up. I gave it up sometime ago because it requires too much uplink power. 2401MHz I have experimented a lot on this frequency recently , using home built aerials on AO13 mode S , and on the much faster moving Dove and Pacsat signals. For the latter I find my twin helix mounted on a pan tilt head on a camera tripod , is the best for following Pacsat and Dove as they flash across my sky. The helices are 6 turns long , so this aerial is no bigger than a pair of binoculars. It works on AO13 CW signals even when this bird is at apogee, but to copy S band SSB I need the bigger quad helix aerial which is bulky but has much more gain ,73 de GM4IHJ@GB7SAN