Multi Band HF / VHF / UHF base antennas
The Comet CHA-250HD is the revised CHA-250B.
The top section of aluminum has been replaced with a solid whip for greater flexibility and less strain on the lower sections in high winds. A uniquely designed broadband vertical requiring NO GROUND RADIALS.
This is EXTREMELY easy to assemble, requires no tuning or adjustments and VSWR is under 1.6:1 continuously from 3.5MHz – 57MHz!
It is not a 1/4 wave vertical, but an end-fed long wire type antenna with a matching transformer in a vertical position.
TX 3.5 – 57MHz
RX 2.0 – 90MHz
VSWR: 1.6:1 or less
Max Power: 250W SSB 75W Digital modes/FT8, etc…
Impedance: 50 Ohm
Weight: 7 lbs 1 oz
Mast Size Required: 1″-2″ diameter
Max Wind Speed: 67MPH
If you have the space, budget and desire to erect a full size antenna system we suggest you do so… bigger is better…however…if you live in an antenna restricted area and must manage with antenna or space restrictions or you simply wish to operate incognito you will be forced to make significant antenna compromises. The CHA-250HD will make the most of these circumstances!
This is a the “magic” behind the CHA-250HD, the transformer matching section.
The transformer on the original CHA-250 had smooth sides. The current version has a heat sink to dissipate heat created inside the transformer.
Yes, some of the RF that enters the power feeding section is turned into heat rather than transmitted as RF, but that is one of the compromises needed to create a broad-band, low SWR, multi-band HF antenna with minimal visual mpact.
5-Band, 1/2 wave rotatable dipole for 40/20/15/10/6 meters
This is the compact dipole used for HF communications on the set of the ABC Television show “Last Man Standing” with Tim Allen. The crowded space above the set required a compact multi-band dipole, and the CHV-5X was selected to solve the problem the minimal space presented.
Compact, lightweight, and easily assembled in either a horizontal, “V” shape or ground-plane configuration. Each band tunes independently of the others.
Comet engineers have specifically designed this antenna for those that desire a milti-band dipole that can be rotated if needed, but do not have a lot of room to install it.
If you have antenna restrictions, neighbors that tend to complain about antennas, simply want to operate without drawing attention…or you want a lightweight multi-band antenna to use in portable or emergency situations, the CHV-5X is a great choice.
40/20M 150W SSB
15/10/6M 220W SSB
Horizontal length: 13 ft approx
Weight: 5 lbs 14 oz approx
Impedance: 50 Ohm
Mounting mast req’d: 1″-2.5″
Typical 1.5:1 or less SWR bandwidth: