dave
shared these priceless pearls of wisdom:
-Thanks jim,
-
-Hate to keep this dragging along, but it sounds like multi conductor
-ribbon wire might be the ticket for a nice wide band antenna.
Don't know, never tried it. I have no idea what the characteristics of the
insulator on ribbon wire is like at VHF, but I suspect it is at least
acceptable, if not good. You would cut the ribbon wire on the diagonal at the
far end of the dipole leaving all the conductors open, and then solder all the
conductors together at the center section of the dipole leg. The diagonal
should be, as I said, 20" at the short point and 21" at the long point from the
center.
How many conductors? Well, we like to make our antennas at least ¼" in rod
diameter or ½" flat tape, so I'd say an inch or so wide with 50% wire fill and
50% insulation fill should be a decent equivalent.
You **will** come back here and let us know how it went, won't you?
-Do you have any suggestions for the toroid? I have lots of room for
-anything I need.
No suggestions for the toroid other than to go to any of the RF ferrite sources
and look for something that will fit and is made of a material that is "good"
(relative term) at 120-140 MHz. Micrometals mix 17 springs quickly to mind.
Do NOT use the Rat Shack "alternator noise" toroid in this application, nor a
toroid salvaged out of a computer power supply. They are LOUSY at VHF.
Jim
Jim Weir (A&P/IA, CFI, & other good alphabet soup)
VP Eng RST Pres. Cyberchapter EAA Tech. Counselor
http://www.rst-engr.com