PAR EndFedz EF-4020
$$···
| Frequency | 7 / 14 MHz - true half-wave resonance on both, no tuner |
| Type | end-fed half-wave |
| Gain | 0 dBi |
| Polarization | mixed |
| TX power | 100 W (spec sheet verbatim: 100 W SSB/CW, 25 W DATA/AM - digital-mode operators read that second number twice) |
| Modes | SSB, CW, AM, FM, digital |
| Length | 2012 cm |
| Weight | 227 g (8 oz) - 0.5 lb (227 g) per the PAR Electronics EF-40/20 specification sheet. |
| Connector | SO-239 (silver/Teflon) on the matchbox - the LC matching network in a UV-resistant ABS housing |
| Mount | portable, tree/mast |
| feedpoint | end-fed LC matchbox, SO-239 |
Estimated (unverified): current retail price (Vibroplex cart hides it from fetch); wire gauge for this specific model (the family overview says #18/#26 copperweld; the EF-4020 sheet doesn't specify)
The end-fed convenience without the random-wire chaos: because the wire is a true resonant half-wave on both bands, there is no tuner, no counterpoise ritual, and no guessing - hoist, connect, operate. The tuning stub lets each band be trimmed independently (rare in dual-band EFHWs), the matchbox is weatherproof, and decades of trail use have made the EndFedz line the reference brand for resonant end-feds.
Two bands is the menu - the wider EFHW world covers 80-10 from one wire at the cost of compromise resonances. The 100 W class rating excludes amplifiers, end-fed feedlines still benefit from a choke regardless of marketing (common-mode current finds a way), and the brand's pass-the-parcel history (PAR -> LNR -> Vibroplex) makes sourcing the current genuine article slightly confusing.
The portable operator's no-drama wire: two real resonances, zero adjustments in the field, and engineering by people who clearly carried their own product up hills. Multiband ambitions point to its broader EFHW cousins; for a 40/20 day pack, this is the benchmark.
The EndFedz line built its reputation on a precise engineering claim: these are not random wires with ununs, they are true end-fed half-waves - resonant, no tuner, no counterpoise network - with the feedpoint relocated to the end of the wire, which is where portable reality (the tree, the operator, the radio) actually lives. The EF-4020 is the dual-band classic: about 66 feet of wire resonant on 40 meters, with the 20 meter resonance arriving via the second harmonic and disciplined by a tuning stub that lets each band be trimmed independently - the detail that separates it from cruder dual-banders.
The honest footnote every EFHW page owes its readers: 'no counterpoise needed' is true in the sense that the design works as shipped - the high-impedance end-feed needs very little 'other half,' and the coax shield plus matchbox supply it - but common-mode current on the feedline is the mechanism, so a choke at the rig end remains good practice the marketing omits. Power is spec'd verbatim at 100 W SSB/CW but just 25 W for data and AM - the number FT8 operators must read - the matchbox is sealed for weather, and the wire geometry is whatever the site offers: sloper from a branch, inverted-V over a limb, flat-top between fences; the spec sheet itself shrugs that polarity 'depends on mounting configuration.'
The brand story is its own small saga with documented dates: designed at PAR Electronics by Dale Parfitt - who built the EndFedz concept on an expired 1980 patent for end-feeding half-wave mobile whips - manufactured by LNR Precision from August 2010, and sold by Vibroplex since September 2019: three logos, one product DNA, with used examples from every era circulating. Its catalog neighbors define the trade space: the 80-10 EFHW class buys more bands with compromise resonances, and the ultralight school shaves ounces for the gram-counters. The EF-4020 remains the disciplined middle: two bands, done properly, packed small.