Par End-Fedz EF-17QRP Instructions manual

ENDFEDZ



EF-17QRP

17M END FED HALF WAVE ANTENNA

ENDFEDZ ARE MONO BAND ANTENNAS. USE ON BANDS OTHER THAN

THE DESIGN BAND WILL RESULT IN SIGNIFICANT COAX RADIATION

AND MAY RUIN THE MATCHBOX

PACKING LIST OF INCLUDED ITEMS:

 EF-17QRP anrtenna
 PL-259 to BNC male adapter (to use BNC eqipped coaxial cable if desired)
 End insulator, manufacturer Spiderbeam
 Tuning stub
 This manual

ASSEMBLY

1. This antenna is essentially a half wave dipole with one important difference– the feedline
is at the end of the antenna.

2. In order to have the least possible influence on the antenna, insulated lines are
recommended for attachment to the insulators. The antenna may be suspended
horizontally, vertically or sloping. Portable operation is easily accomplished by

suspending the far end from a tree limb and letting the matchbox hang just above the
ground.

3. The antenna has been used from hotel rooms by hanging the matchbox end just outside
the window and letting the far end hang, or preferably pulling it away from the building
with a guy attached to the end insulator.

4. Tuning is best accomplished by using an antenna analyzer attached to the far end of the
coaxial cable that will be used with the antenna. Once the initial resonant frequency is
established, the antenna may be tuned just like a dipole. Shortening the far end by 1” will
raise the resonant frequency approximately 50 kHz. Trim or (better) fold the wire back
on itself and wrap to shorten the antenna. If too much wire is removed, the included
tuning stub may be attached to the stud at the matchbox end and trimmed to establish
resonance to the desired frequency. Fine tuning may be accomplished by changing the
orientation of the stub with regard to the main radiator (I.e. rotating the stub and
retightening the hardware. Tighten the hardware just enough to compress the lockwasher.

5. Once you are satisfied with the overall length of the radiator, lace the wire and tie off a
support rope through the provided insulator.

6. Fig. 1 illustrates some mounting ideas.

Fig. 1

SPECIFICATIONS

Polarity: Depends on mounting configuration
Design Z: 50 Ohms
Frequency of operation: 18.068-18.168 MHz
V.S.W.R. Bandwidth: 400 kHz 1.5:1
Power Handling: 25 watts SSB/CW, 12.5 watts digital
Weight: 5 ounces
Length: 25’6”
Hardware: Stainless Steel
Connector: Silver/Teflon SO-239, PL-259 to BNC male

adapter included

Radiator: #22 AWG Poly Stealth

EndFedz ®

Vibroplex LLC

1001 N. Broadway St.

Knoxville, TN 37917

[phone]

www.vibroplex.com [e-mail]