Either run LMR-400 all the way (70-foot) or for lower loss run 50-foot 1/2-inch hardline (Andrew Heliax LDF4-50A) + 20-foot of LMR-400. Use N-female connectors on the hardline and N-male on the LMR-400.
Speaking about coax lines i just get from an CATV installer who was working in my backyard replacing an old heliax line (That i was watching for over 2 weeks) about 4 run of 200 feets of old master line 75 ohm heliax the one who can be fitted nicely with a PL-259 connector.
The killing question!!! Did any one used this type of coax on a RX line with a mast head preamp on 432Mhz 1.2Ghz and 2.4Ghz? I know on a TX line the mismatch will give a SWR around 1.5 making the line probably too lossy on TX at microwaves frequencies even with both end adapted.
The installer was very happy to don't have to coiled about 800 feets of coax in about 4 feet of snow behind about 6 back yards full of winter stored items and sheds. The final destination of this coax line was the trash container...
My small ecological contribution!
Thank's for your input
Luc Leblanc VE2DWE Skype VE2DWE www.qsl.net/ve2dwe WAC BASIC CW PHONE SATELLITE