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Twin lead or coax for downlead from FM antenna?

I have about a 25-30' run from my attic antenna to my tuner. The antenna has twin lead (300 ohm) output and the tuner has a coax only input (75 ohm). I can either use twin lead and a transformer at the tuner end, or put the transformer at the antenna and then run RG-6. Any idea on which would be better in terms of signal loss, noise, and longevity? I understand that these criteria may be mutually exclusive. Tuner is a Yamaha T-85 and antenna is a Winogard X type omnidirectional. I do not want to fuss with a directional/rotor set up.
128x128swampwalker
abstract7
541 posts
 
Coax run should shield noise and give you a better overall signal.
swampwalker's avatar
swampwalker OP
5,138 posts
 
OK, thanks guys. Since the cable is in my attic which is quite dry, weatherproofing should not be an issue. Now I just have to get my butt up thru the scuttle and switch over to the coax (RG-6).
nexusrlee
6 posts
 
I agree that you should run a quad shield RG-6 coax line. I just though I would mention that directly connecting an antenna or cable connection to your audio/video system could have disastrous results without some kind of surge suppression to protect the components. You may also create a ground loop that will cause an annoying hum. I recommend the Monster Power series from Monster Cable. The HTS1000 or HTS2000 will provide protection for all your equipment. http://www.monstercable.com/product_info/infosheet_mpwr_hts2000.html
j_k
234 posts
 
Use the RG-6... If the antenna in the attic, it doesn't need surge protection; If it is outdoors, surge protection is a really good idea. The issue one should watch is the possibility of added EMI / RFI that can occur when adding a tuner to a system. One time I was troubleshooting this and found when I started disconnecting everything in the house that the downfeed on my FM antenna was picking up some kind of RFI from some local high power CB transmissions. Pounding a copper rod into the ground with a 00 cable attached to the rod and ground bus bar added to my audio ground knocked it out. Everything in my audio system is chassis grounded to this buss in a "star" configuration (which the shield of all my coaxes are also attached to.
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