After reading SiG's post on Radio Propagation, and seeing his comments about the big 6 Meter opening he was enjoying, I made some comments about rarely operating 6 Meters, but enjoying the times I did.
In mentioning that I only have one radio that will transmit on 6 Meters, and that radio will be going on eBay soon, he replied that I should make a 6 Meter Dipole, hoist it up, and give my hand a try at the upcoming ARRL June VHF Contest that's scheduled for this coming weekend.
Hmmmmm....do I have enough "stuff" to build a decent antenna?
Wire? Check! Plenty of 12 gauge Davis RF "Flex Weave" on hand.....
Center insulator? Check! I have a Hy-Gain center insulator new-in-box.....
End insulators? Check! Would you like plastic or ceramic?
Support rope? Oh, yeah, got several hundred feet. Would you like new, or slightly used?
So I cracked the books, came up with some dimensions, and proceeded to cut wire, and belay the insulators to the ends of it.
Took me an hour to round up all the bits and pieces, and about another hour to lay out the wire, measure it to length and cut it, install the end insulators, crimp/solder some ring lugs on the free ends, and bolt it all together.
Here it is stretched out on the garage floor. It's about 9' end-to-end.
Oh, and since it's a Dipole ("Balanced") antenna being fed with Coaxial Cable ("Unbalanced"), we'll need a "Choke Balun" (more accurately a "Line Isolator") to keep RF current OFF the outside (The Shield) of the coax.
A simple VHF coaxial choke consists of 4 turns of cable, "solenoid wound", in a ~3" diameter. I wound mine using 48" of RG-8X cable and a cardboard Morton Salt container as a form. I put some cables ties on it to keep it from unwinding. This took another couple of hours to round up the parts, find something to use as a 3" coil form, cut the cable and put connectors on it, wind it, and secure it with cable ties.
Here's my feed line choke. Identical in function to the one I made for my 20 Meter (14MHz) vertical, but scaled down for 6 Meter (50MHz) operation.
And all put together and waiting to be installed. I taped the coax connection to the center insulator, both for some weather proofing, and to prevent the connector from loosening up when the antenna sways in the wind.
I was planning on hoisting it up today and connecting my antenna analyzer to it, BUT....it's windy as all get-out, drizzling on-and-off, and just not a nice day to do it. I'll get it hoisted up and swept on Tuesday. That gives me tonight to get the radio and power supply set up and ready to connect to the antenna once I've got it in the air.
This is the first 6 Meter dipole I've ever built, and I'm sure I'll be in for a few surprises once it's up in the air and I connect the analyzer to it.
I'll be running my Old Faithful Yaesu FT-847 transceiver "Satellite Radio" as it's the only rig I have with 6 Meters. I'll easily be able to get this dipole mounted "In The Clear" more than a half-wavelength above ground, so it should work about as well as a dipole can work. And with 100 Watts of RF power out of the radio, and maybe 35' of low-loss feedline, I should be able to work most of what I can hear. If there's a good opening I should be able to make a lot of voice contacts, my preferred mode. If voice mode is too noisy/weak for me, I can switch over to one of the digital modes like FT8, and make lots of contacts.
More pix when it's in the air.