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HV7A Mobile Antenna System
General Information
HV7A has 5 band capability—6m/2m/70cm, plus 2 HF bands though use of loading coils. The HV7A is supplied with HVC28 (10m) loading
coil. There are four optional HF coils available: HVC7 (40m), HVC14 (20m), HVC18 (17m), and HVC21 (15m). The HV7A has a fold-over
structure which allows for entrance into parking structures (i.e. garages, buildings, etc.). Use DIAMOND model MX62M Duplexer for
single antenna operation with ICOM IC-706 series, Yaesu FT100 or for combining HF & VHF transceivers.
Specifications
Bands Supplied
10m/6m/2m/70cm
Power, PEP:
HF 120 watts / VHF 200 watts
Mount Connection:
UHF
Length:
54” (with the HVC7 installed, total length is 80”)
VSWR:
1.5:1 Nominal–HV7A (10m/6m/2m/70cm)
Frequency:
6m: 50-54 MHz; 2m: 144.5-148 MHz; 70cm: 440-450 MHz
(Nominal BW)
HVC7 (40m): (28 KHz)
HVC14 (20m): (60 KHz)
HVC18 (17m): (140 KHz)
HVC21 (15m): (180 KHz)
HVC28 (10m): (390 KHz)
Element Phasing:
6m–1/4
λ
, 2m–5/8
λ
, 70cm–2-5/8
λ
Recommended Antenna Mounts:
Diamond K400C or K600M
Recommended Duplexer:
Diamond MX62M
Installation Instructions
PRECAUTIONS:
(1) The HV7A requires vehicle ground.
(2) If installing HVC7 (40m) loading coil, install on top (vertical position) only.
Some installations may require a nylon fish line to relieve stress on vehicle
mount.
(3) The HV7A 6m/2m/70cm tuning assumes that at least one loading coil is
mounted at the top end. VSWR may be out of specification without the coil(s).
(1)
Choose mounting location to insure maximum strength of
mount, and proper vehicle ground to yield best performance.
(2)
Assemble HV7A with desired loading coil and install on
vehicle mount. (HVC28 10m coil is included in package.)
NOTE: Metric Hex wrenches are enclosed.
READ THIS BEFORE TUNING ANTENNA:
Included are two 6” pieces of 16ga copper wire to assist in tuning
antenna coils. Use copper wire in place of original tuning
elements to simplify tuning process. Once proper tuning is achieved,
trim original steel elements to their desired length and verify adjust-
ment.
Tuning the HV7A Antenna:
3)
NOTE: You must tune 6-meter band
before adjusting the HF coils. Always check
upper and lower bandwidth edges with quality
VSWR meter before trimming tuning elements.
(Omit 6m portion if not to be used.)
Replace the stock 6m tuning element with one
of the enclosed 6” copper wire. The element
can be replaced by loosening setscrew on
element support bracket #981116. It is important
to leave additional 1/2-3/4" below support
bracket for additional adjustment.
(See Illustration).
981113
M4 Set Screws
HVC28/10m
Loading Coil
981113
981113
981113
HVC28
981101
Loading Coil/
Foldover Assembly
981103
Lower Whip Element
981104
Phase Coil
981102
Upper Whip Element
981105
50 MHz Coil
981117
50 MHz Tuning
Element
981116
50 MHz Element
Support Bracket
½” - ¾”
Tuning element
67421
