Or better still,
Cut and tune your inverted vee half way between phone and cw. Place a 1/4
wave piece of 72 ohm coax between the feedline and the center insulator. The
SWR is nice and low across the entire band! You will no longer need to put
up and take down your antenna each time you want to change from CW to phone
and back.
This also works well for slopers. I have a full sized sloper from the top of
my tower and I never have to take it down and put it up (a real pain with a
sloper with one end at 120 feet. SWR less than 1.5:1 from 3.5 to 3.9. Since
the coax has to hang out there, I decided to try RG6 as my 1/4 wave piece of
coax because it is lighter than RG11. Works fine with my Alpha.
I can't remember the exact frequency to cut the 1/4 wave coax but you need
to remember the Velocity Factor in your calculation.
Bill, W5VX
>-----Original Message-----
>From: cq-contest-bounces@contesting.com [mailto:cq-contest-
>bounces@contesting.com] On Behalf Of Georgek5kg@aol.com
>Sent: Friday, April 30, 2004 10:09 AM
>To: w9wi@earthlink.net; CQ-Contest@contesting.com
>Subject: Re: [CQ-Contest] awesome upgrades to the 8 band vertical!!
>
>In a message dated 4/30/2004 10:46:53 AM Eastern Standard Time,
>w9wi@earthlink.net writes:
>Cut them for CW, but cut the support ropes at the end for phone. When
>operating phone, wrap the extra wire around the antenna, going back
>towards the center insulator. When operating CW, let the extra wire
>droop down towards the ground.
>This is a good suggestion, especially for 80 and 160 inverted vees, where
>you
>can reach the ends from the ground, or at least lower the ends to where you
>can reach them.
>
>Here is another trick. Cut your inverted vee for SSB. Install an SO-239
>coax connector into the distant end of each leg of the inverted vee. (Cut
>the
>leg one foot from its distant end, and connect the SO-239's center pin to
>one
>wire, and its ground to the other wire). When operating on SSB, connect
>shorted
>PL-259's each SO-239. For CW, attach a length of coax, shorted at its
>distant end, into the SO-239. This effectively adds length to the inverted
>vee,
>hereby making it usable on CW.
>
>For 80m, here is what I would do: Make the inverted vee 119' long for
>approximately 3900 kHz, or 59.5' on each leg. Install SO-239's as
>described above.
>For SSB, attach shorted PL-259's to each SO-239. For CW (3600 kHz), add 6'
>sections of shorted coax to each SO-239 connector that you have installed
>at
>the distant end of each leg. Will work like a charm!
>
>73, Geo...
>
>George Wagner, K5KG
>941-312-9450
>941-312-9460 fax
>941-400-1960 cell
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