73 Review by David R. Margolts AG8L

The GAP Voyager DX-IV Vertical

GAP Antenna Products, Inc.

6010 8% B N. Old Dixie Highway Vero Beach FL 32967 Telephone: (407) 778-5728 Price Class: $390; guy rope, S39,

Operate 160 through 20 meters with this high performance antenna

For the last two years I've been DXing with

100 watts and two verticals, the Cushcraft R5 and the GAP Challenger DX-VI. The GAP DX-VI is a fine antenna, but its performance on 80 meters is limited by its size and narrow bandwidth. I wanted something better for 80, and also some way to get on 160 meters, Dipotes seemed like a poor choice because of the difficulty in getting them io an effective height. At the 100 watt power level 80 and 160 meters are especially difficult because of the typically higher noise levels and weaker signal strengths, so an effective antenna is a must.

Enter the GAP Voyager DX-IV, the big brother to the GAP DX-VI. The DX-IV is 45 feet tall and covers 160, 80, 40 and 20 meters. The DX-IV was created specificaffy to provide an antenna solution on 160 and 80 meters; the coverage of 40 and 20 meters is something of a bonus. Aboui 90 kHz is covered on 160 meters, wiih full coverage on the other bands.

Photo A The GAP Voyager DX4V offers 160 through 20 meter operation.


If you're not familiar with GAP verticals, picture a dipole mounted on end, That is the best way I have to describe the GAP DX-IV to you. The feedline attaches to a center insulator (the "GAP") about halfway up the antenna. From there, the feedtine comes down inside the lower section of the antenna and exits through the bottom, terminating in a PL-259 connector. Tunjng rods attach to three sides of the antenna to provide multiband coverage, and a capacitance top hat (a wire ring six feet in diameter) at the top of the antenna increases the electrical height for 80 and 160 meters.

Unlike traditional verticals, an extensive ground radial system is not required. Only three radials {the manufacturer caTIs them counterpoise wires) measuring 57 feel are required. The only restrictions on them are that they must be insulated, and they must not run too close to your feedline. They can be buried, and they can zigzag, if necessary, to fit your site. You'll need to provide the wire (it doesn't come with the antenna), but just about any insulated wire will do fine.

I had my DX-IV shipped to my office. It can be shipped by UPS, but you should be prepared to receive a long box. E got some sense of this when the receptionist called and told me, with a note of panic in her voice, that there was an antenna for me in the lobby. She didn't sound too happy. The box is nine feet long, which is the longest allowed by UPS, and weighs about 30 pounds, i managed to get it home in my Taurus by running it diagonally through the car with one end sticking out the front passenger window. If you try this during rush hour, remember to stay on the left side of your lane.

When you unpack the box, you wilt find several large pieces of tubing, the GAP section with pre-attached coax, and many smaller pieces of tubing. The smaller pieces of tubing are packed inside the larger diameter tubing for protection during shipping. A small box of hardware, the top hat wire, instructions, and a nut driver round out the parts inventory.

Before You Start.,.

Before the antenna can be put up, several things must be done. A suitable site is the first requirement. You'll need a clear area at least 45 feet long with no obstructions (like tree branches or electrical wires) above it, Four pairs of guy ropes spaced 90 degrees apart support the antenna and attach to the ground 25 feet from the base of the antenna, so the 45-foot figure should really be closer to 70 feet to take this into account. The location of the counterpoise radials should also be considered when selecting a site, although you have more flexibility with their placement. The tuning rods at the bottom of the antenna will be hot with RF during use, so an enclosure should be included if children or pels can enter the area.

Another site consideration is the proximity of other vertical metal objects- Allow at least 70 feet separation from towers, other vertical antennas, aluminum-sided buildings, and so forth. My GAP DX-VI antenna is the closest metai object to the DX-IV, at a distance of just over 70 feet, and it has not caused any problems,

The second requirement is to obtain suitable guy ropes. I assumed this would be easy as I ordered them with the antenna. Unfortunately, the rope was out of stock and had to be back-ordered, With a major contest quickly approaching, 1 was determined to get 1he antenna up. so 1 looked for suitable rape locally. Despite being in a major metropolitan area, f was unable to find a good replacement. The guy rope for the antenna should be rated for 300 pounds load, have good UV resistance, and not stretch under tension. This combination of requirements is almost impossible to find in hardware store rope. I settled on a 240-pound-rated Poly (polypropylene) rope, but ) used it knowing that it would need replacement within a season due to its poor resistance to sunlight. The 300-pound load rating will keep the antenna standing in a 80 mph wind, so you can get by with something less for temporary user like Field Day, You'll need 350 feet of rope in all. cut into eight pieces during assembly for the eight guy ropes.

You can use a variety of ground anchors for the guy ropes. I took a different approach as 1 didn't want to give up any lawn space to the guy ropes angling down from the antenna. Instead of ground anchors, I placed four 10-foot treated 4x4s in the ground, 25 feet from the base of the antenna, spaced 90 degrees apart, The 4x4s were buried four feet deep and anchored with one bag of ready-mix concrete each. Screw eyes were placed about 5-

Photo A The GAP Voyager DX4V offers 160 through 20 meter operation.

WE'VE GOT YOU COVERED C228A-Twin band 2 Meter/220 MHz. C288A-S

C228A-The first and only HT with 2 Meters and 220 MHz

Frequency range RX 130-174 and 200-245 MHz (approx)

TX Ham bands only on 2 Meters and 220 MHz. MARS CAP modifiable, permits required.

2.5 Watts power output with standard battery (CNB151)

5 Watts with 12V battery (CNB152) Long life battery (CNB153) Power cord for mobile operation (CAW150) Three power levels (L) (M) (H)

For more information on this and other STANDARD products contact your nearest dealer or call STANDARD Amateur Radio Products at »3121 763 0081

Specifications, price and features are subject to change without obligation o notice. All products carry a ONE YEAR limitejfiira^Nty

Various Scan modes.

200 Channel Memory Capacity—40 Standard. /

Code Squelchfl"one Squelch.

Built-in key pad under the front slide-cover. /

Receives from 115 to 249 MHz. Transmits 220 MHz ham band only.

AM detector for Aircraft. MARS/CAP modifiable, permits required.

2.5 Watts power output with standard battery (CNBI84)jH|

5 Watts with (CNB182). Long life battery (CNB183). j flnp'

Wake-up feature turns the radio on automatically.irou can receive a specific call from another station even if the power is in the off position. Current drain in the Wake-up mode is only 3 mA.

Easy and Quick to address/store memory channels. Vacant memory channels are automatically scanned and located.

DTMF Memory.—10 different DTMF memories, each accommodating up to 15 digits, with the touch of a key.

Also available is the STANDARD C188A for 2 meters and the

C488A for 440 MHz. C288A-The first and only HT with 2 Meters and Aircraft receive coverage with 220 MHz transmit.

40 Memories plus 2 Call memories. 20 per band limited.

CTCSS Encode Decode included. \ ^ '

DTMF Code Squelch and Paging modes. \

Receiver sensitivity is an unbeatable 0.158 uV for 12dB SINAD Unbeatable out-of-band sensitivity.

Clone mode allows you to quickly program a friend's new STANDARD HTfrom yours. All memory contents are copied over the air from one HTto the other.

Also available is the STANDARD C528A. C628A, C558A

STANDARD Amateur Radio. Products. Inc P.O. Box 48480, Niles. Illinois 60648

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