Hy-Gain DX-77A

The "DX-77-A" is an omnidirectional, self-supporting, automatic-bandswitching vertical radiator which operates on the 10, 12, 15, 17, 20, 30 and 40 meter Amateur bands. No ground radials are used with the DX-77-A. The DX-77-A design is based upon an off-center-fed dipole, sometimes called a "Windom" antenna. Highefficiency high-power traps are used to isolate the active sections of this antenna.

The DX-77-A uses a heavy-duty tiltable mast clamp which will accept masts of up to 2 118" inches O.D. The entire antenna may be easily raised and lowered for tuning purposes and for recreational - vehicle (RV) installations. The DX-77-A also features an overall length of 29 feet (8.8 m), which contributes to exceptional bandwidths on 40 and 20 meters.

Frequency Bands:	2:1 VSWR Bandwidth
40m 7.0 - 7.3 MHz	100 KHz min.; 150' KHz typ.
30m 10.1 - 10.15 MHz	100' KHz min., 150 KHz tpy.
20m 14.0 - 14.35 MHz	200 KHz min., 250 KHz typ
17m 18.068 - 18.168 MHz	200 KHz min., 250: KHz typ.
15m 21.0 - 21.45 MHz	400 KHz min., 500 KHz typ
12m 24.89 - 24.99 MHz	300 KHz min., 400 KHz typ.
10m 28.0 - 29.7 MHz	1500 KHz min., 1700 KHz typ.

VSWR' of Resonance............................. .. .....................................................less than. 1.5:1
Maximum Power (at 95° F) ............................................ 750 watts ave., 1500 watts PEP
Gain..... . ........................................unity gain (compared to half-wave vertical dipole)
Input Impedance.....................................................................................................50 ohms

Total Height.……........................ ......................................................... 29 feet (8.8' m)
Bottom Radial Elements .........................................................................4 each, 5 feet (1.5 m)
Allowable Mast O.D. . ..................... ................................1.75 - 2.125 inches (44- 53 mm)
Recommended Masts8 to 10 foot length) .....…........ Aluminum, 2 inch O.D., .125 wall min Steel, 2 inch O.D., :058 wall min.
Weight................... ... ............................................……………………... 25 lbs. (11.35 kg:)
Wind Area . ... .... ............. ....'..............………………………........ 1.9 sq. ft. (.1767 sq. m.)
Maximum Wind Speed (unguyed) ........................................................ 60 mph ( 96.77 Kmph)

Download the manual here. 

Bands 10, 15, 17, 20, 30, and 40 Meters
Max Power 1500 Watts PEP
Input Connector SO-239
Mechanical Specifications
Height 29 feet
Weight 25 pounds
Wind Survival 60 MPH (no guy)
Recommended Mast Size 1.75 in - 2.125 in. OD