The Hy-Gain DX-77A 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.  High efficiency high-power traps are used to isolate the active sections of this antenna.

The DX-77A uses a heavy-duty tiltable mast clamp which will accept masts of up to 2 1/8" inches O.D.  The entire antenna may be easily raised and lowered for tuning purposes and for recreational - vehicle (RV) installations.  The DX-77A also features an overall length of 29 feet (8.8 m), which contributes to exceptional bandwidths on 40 and 20 meters.

DX-77A Vertical Antenna Instructions (243K pdf)

Specifications

 

Electrical.

  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 at 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

 

Mechanical:

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 Mast (8 to 10 foot lg)....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)

LIMITED WARRANTY

Hy-Gain warrants to the original owner of this product, if manufactured by Hy-Gain and purchased from an authorized dealer or directly from Hy-Gain to be free from defects in material and workmanship for a period of 12 months for rotator products and 24 months for antenna products from date of purchase provided the following terms of this warranty are satisfied

1. The purchaser must retain the dated proof-of-purchase (bill of sale, canceled check, credit card or money order receipt, etc.) describing the product to establish the validity of the warranty claim and submit the original or machine reproduction of such proof of-purchase to Hy-Gain at the time of warranty service. Hy-Gain shallhave the discretion to deny warranty without dated proof-of-purchase. Any evidence of alteration, erasure, or forgery shall be cause to void any and all warranty terms immediately

2. Hy-Gain agrees to repair or replace at Hy-Gain’s option without charge to the original owner any defective product under warranty, provided the product is returned postage prepaid to Hy-Gain with a personal check, cashiers check, or money order for $8.00 covering postage and handling

3. Under no circumstances is Hy-Gain liable for consequential damages to person or property by the use of any Hy-Gain products

4. Out-of-warranty Service: Hy-Gain will repair any out-of-warranty product provided the unit is shipped prepaid. All repaired units will be shipped COD to the owner. Repair charges will be added to the COD fee unless other arrangements are made

5. This warranty is given in lieu of any other warranty expressed or implied.
 
6. Hy-Gain reserves the right to make changes or improvements in design ormanufacture without incurring any obligation to install such changes upon any of the products previously manufactured.
 
7. All Hy-Gain products to be serviced in-warranty or out-of-warranty should be addressed to:

Hy-Gain
308 Industrial Park Road
Starkville,
Mississippi 39759

and must be accompanied by a letter describing the problem in detail along with a copy of your dated proof-of-purchase.

8. This warranty gives you specific rights, and you may also have other rights which vary from state to state.

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