OK, Luc. To make this decision you need to do the math. But you can just try comparing performance by installing the preamps at the antenna and at the shack and make your own evaluation. I'm guessing that is not convenient as antennas are on a tower.
You mention running two coax lines "1/78". > 73, Ed - KL7UW, WD2XSH/45 ====================================== BP40IQ 500 KHz - 10-GHz www.kl7uw.com 500-KHz/CW, 144-MHz EME, 1296-MHz EME DUBUS Magazine USA Rep dubususa@hotmail.com ======================================
It is a Heliax 45' lenght of 7/8"... and here is the the relay info's i have:
http://www.recycledgoods.com/18955_RelComm%20Technologies_RDL-2N1D4%20SR006_... %20SR006_.html
There was some discussion about RelComm Technologies on the moon net in 2008: http://list-serv.davidv.net/pipermail/moon-net_list- serv.davidv.net/2008-November/014898.html
If their figures are reliable i will put them in your spread sheet with the preamps figures Icom AG-35 and AG-25 and the rig is the FT-847.
As i don't want to have an EME class station (Just working leo's) i will probably not be able to tell the difference even if there is one but as you said the only one way to be 100% sure is to tested it but this will have to wait until next summer If the antenna will survive our next 24hrs of predicted freezing rain...
Thank's for your help Ed
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Luc Leblanc VE2DWE Skype VE2DWE www.qsl.net/ve2dwe DSTAR urcall VE2DWE WAC BASIC CW PHONE SATELLITE