Thread: Rca ant751
View Single Post
Old 6-Jun-2017, 2:59 AM   #76
Retired A/V Tech
Join Date: Aug 2012
Location: S.E. VA
Posts: 2,545
I suspected that multipath reflections were causing a problem and decided to add a reflector element to the VHF folded dipole. A cardboard box is used as a temporary support.

The reflector is 13" behind the VHF dipole and consists of a 24" length of 1" aluminum tubing with a 12" length of 7/8" tubing in each end and clamps. The length has been adjusted to 27.7". I also tried a strip of aluminum foil on a yardstick with the same results:

The reflector improves the reception:

and the scan looks a lot better:

Attached Images
File Type: jpg Loc1tubingRefl.jpg (126.0 KB, 2092 views)
File Type: jpg Loc1foilRefl.jpg (153.1 KB, 1854 views)
File Type: jpg Loc1DiagwithRefl.jpg (109.1 KB, 2052 views)
File Type: jpg CH13Loc1withRrefl.jpg (53.5 KB, 2051 views)
If you can not measure it, you can not improve it.
Lord Kelvin, 1883

Last edited by rabbit73; 6-Jun-2017 at 3:07 AM.
rabbit73 is offline   Reply With Quote