Alpha Delta DX-CC
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| Frequency | 80m: 3.5-4.0 MHz, 40m: 7.0-7.3 MHz, 20m: 14.0-14.35 MHz, 15m: 21.0-21.45 MHz, 10m: 28.0-29.7 MHz |
| Bands | 80m, 40m, 20m, 15m, 10m |
| Modes | SSB, CW, AM, FM, digital |
| Connector | SO-239 |
| Year | 1990 |
| feedpoint | SO-239 |
Estimated (unverified): introduction year (~1990)
A pre-assembled five-band parallel dipole. It uses ISO-RES coils instead of traps, which gives broader bandwidth and no trap capacitors to fail. No cutting, measuring, or soldering is required; hang it between two supports as a flat-top or inverted-V and connect the coax on 80/40/20/10m without a tuner (15m needs a tuner). Rated 1000 W PEP. 12-gauge copper wire with stainless hardware. A long-running Alpha Delta design.
ISO-RES coils add some loss on every band. The 82 ft length needs two reasonably tall supports set far apart. Per-band performance is below a dedicated single-band dipole. It costs more than a homebrew wire antenna. No WARC-band coverage without a tuner.
A pre-built multiband wire antenna for operators who want one without building it. Per-band performance is below a single-band dipole, but it is easy to put up: hang it between two supports, connect the coax, and it works on 80/40/20/10m without a tuner; 15m needs a tuner.
The parallel dipole is the put-it-up-and-forget-it answer to multiband HF, and the Alpha Delta DX-CC is one of the longest-running examples. Hang 82 feet of wire between two supports, connect the coax, and you have 80, 40, 20, and 10 m without a tuner, four bands from one feedline and no antenna switch.
What makes it tick is the ISO-RES coil. A conventional multiband dipole uses traps, which are parallel-resonant circuits with capacitors that quietly degrade and eventually arc over under high power. The DX-CC swaps those for low-Q resonant coils on the 80/40/15 m wires, with separate full-length wires for 20 and 10 m. The payoff is broader bandwidth than a trapped dipole and, more importantly, no capacitors to fail. It is rated at 1000 W PEP, on 12-gauge copper with stainless hardware, so it shrugs off weather and amplifiers alike.
One honest caveat the packaging does not shout about: 15 m is not a naturally resonant band here. It rides on the third harmonic of the 40 m element, which lands slightly off, so you will want an antenna tuner for 15 m even though the antenna is sold as a five-bander. A tuner also opens up the WARC bands (30, 17, and 12 m) as a bonus. If 82 feet is more than your lot allows, the shorter DX-EE folds the same idea into about 40 feet by dropping 80 m.