Greyline Upgrades · DXF and DXV Compatible
The 4' Extension — Four More Feet of Aperture.
Height is aperture. The 4' Extension takes your Greyline up one step — 12 to 16, 16 to 20, 20 to 24, or 24 to 28 feet — with the same 2-inch aluminum, the same splice, and the same stainless hardware as the rest of your antenna. It still works every band, 160 through 6; the extra length pays most on 40, 80, and 160, and it moves the bonus gain down the dial.
In the Kit
One 4-foot, 2-inch upper section and its transition splice, with matching stainless hardware. It installs just below the top section of your antenna. Ships bagged and boxed, couplers already bolted on.
What Four Feet Buys
In NEC modeling over average ground, going from 20 to 24 feet lifts 40 meters by about half a decibel and moves the strongest bonus from 10 meters toward 12, with more gain on 30 through 15. Going from 16 to 20 is a similar step. One well-known DXer called his 20-to-24 upgrade night and day; others notice it less. Physics sets the gain; propagation decides how often you hear it.
See every combination, band by band, in the VDA Optimizer →
Before You Order — Your Pole's Year
Greylines built in 2021 and earlier used a slightly different tube wall. If yours is one of them, it needs a fit splice so the extension seats properly — we have them. Put your antenna's year in the order notes, or call 435-200-4902, and we will send the right parts the first time.
Wind Ratings Follow the New Height
Once extended, your antenna carries the ASCE 7-10 rating of its new height — flag up / flag down: 16 ft 75/115, 20 ft 60/90, 24 ft 50/70, 28 ft 35/55 MPH. Lower the flag when weather threatens. Extending a 28-footer takes you into our experimental, guyed range; call before you order that one.
Pair It With
The Tilt-Up Base
Add height without a ladder: walk the pole down to waist height, add the section, and walk it back up alone.
View Tilt Base →Or Go Further: The 9' Whip
Nine feet of adjustable upper radiator on top of any Greyline, strongest on 17 meters on the Skylines.
View the Whip →From the Field
“Going from the 20 ft to the 24 ft antenna made a very big difference. Now I can run in most contests both domestic and DX when condx are decent on 40 thru 10.”
— Bill · K3WA · PVRC President · North Carolina HOA
Gain figures: NEC modeling over average ground. Further reading on the Bookshelf. Every install document is on Documents & Forms.
Questions? Call 435-200-4902. Ham Radio is fun again! Pass it on… 73, Jon KL2A