[ARC5] Why an UNUN - and a drift into TCS territory

Laura and Jim mcenfalz at humboldt1.com
Wed Oct 24 22:29:44 EDT 2012


I successfully run my TCS into a dipole in this manner: 

Crank the loading inductor to near zero turns, add a 365 PF series cap outboard, then add 1:4 autotransformer to feed the coax. 
Hot and ground go to separate posts on the autotransformer box, coax out the other side, T-network "tuna" to an NVIS dipole. I get good reports and the full 20W out. 

Now my ARC question: I have a 20 foot portable whip and 16 radials out on the lawn 30 ft away from the shack. What's the best way to feed the whip? 
a) Beefy cable from the TX antenna post to the whip feedpoint, separate ground wire out to the radials? 
b) Above mentioned UNUN (1:4) set-up and co-ax to the whip? Of so, what do I do at the end of the coax? Install another UNUN (4:1) to take the 50 ohms back to 12?
d) None of the above (most likely............hihi)

73 DE JIM K6FWT



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