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<blockquote data-quote="s-band" data-source="post: 968912" data-attributes="member: 407744">on Jonti's JAERO page? <a href="http://jontio.zapto.org/hda1/jaero.html" target="_blank">JAERO</a> That looks like a simple, cheap method. I'm haven't looked up which way round the polarisation is but he gets it to work both ways since it works with and without the dish, probably due to poor x polar rejectionYes, they are but it will only lose 3dB. If there is nothing to interfere from the other circular polarisation, it will not matter too much. Log periodics as dish feeds can be problematic as the effective feed point moves along the length of the log periodic with changing frequency. Your patch should be better. Long ago, when the world was analogue, I put a dipole in front of a C band feed to listen to NPR (National Public Radio) which had a permanent transmission on L band Inmarsat.The log shown may be from <a href="http://www.wa5vjb.com" target="_blank">Printed Circuit Board Antennas| Commercial and Hobby Antennas</a> who does dome very affordable PCB antennas. He also sells PCBs for MMIC amplifiers at 5 for $10 which would be handy for these projects.This link leads to lots of info <a href="http://www.rtl-sdr.com/tag/inmarsat/" target="_blank">inmarsat Archives - rtl-sdr.com</a> including helical antennas and feeds. I used a 4 turn one on S band with an 80cm offset dish. Here's one someone did for Inmarsat <a href="http://www.rtl-sdr.com/building-a-l-band-helical-antenna-for-inmarsat/" target="_blank">Building an L-band helical antenna for Inmarsat - rtl-sdr.com</a></blockquote>

[QUOTE="s-band, post: 968912, member: 407744"] on Jonti's JAERO page? [URL='http://jontio.zapto.org/hda1/jaero.html']JAERO[/URL] That looks like a simple, cheap method. I'm haven't looked up which way round the polarisation is but he gets it to work both ways since it works with and without the dish, probably due to poor x polar rejection Yes, they are but it will only lose 3dB. If there is nothing to interfere from the other circular polarisation, it will not matter too much. Log periodics as dish feeds can be problematic as the effective feed point moves along the length of the log periodic with changing frequency. Your patch should be better. Long ago, when the world was analogue, I put a dipole in front of a C band feed to listen to NPR (National Public Radio) which had a permanent transmission on L band Inmarsat. The log shown may be from [URL='http://www.wa5vjb.com']Printed Circuit Board Antennas| Commercial and Hobby Antennas[/URL] who does dome very affordable PCB antennas. He also sells PCBs for MMIC amplifiers at 5 for $10 which would be handy for these projects. This link leads to lots of info [URL='http://www.rtl-sdr.com/tag/inmarsat/']inmarsat Archives - rtl-sdr.com[/URL] including helical antennas and feeds. I used a 4 turn one on S band with an 80cm offset dish. Here's one someone did for Inmarsat [URL="http://www.rtl-sdr.com/building-a-l-band-helical-antenna-for-inmarsat/"]Building an L-band helical antenna for Inmarsat - rtl-sdr.com[/URL] [/QUOTE]

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