Hy-Gain DIR-73, Инструкция по эксплуатации

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Operation
Connect the end of your transmission line to a
good quality SWR meter or Thruline watt-
meter and then to your radio. While using
lower power (less than 200 watts output),
check the VSWR across each band from 7.0
to 7.3 MHz. Record this information for
future reference. See Attachment 1 in Chapter
5. Check the VSWR periodically to ensure
proper operation.
This completes your installation of the Dis-
coverer 7-3. Happy DX'ing!
When storing this antenna (or if awaiting
installation), care should be taken not to
damage any assembly. Do not leave the
elements in a grassy area, as wet grass will
stain the aluminum.
VSWR Calculations
When using a meter, which indicates forward
and reflected power levels, you may wish to
convert these readings to VSWR. The correct
formulas are:
Maintenance
The Discoverer 7-3 antenna is designed to be
relatively maintenance free. All hardware, ex-
cept for seven (7) long bolts used in the
boomto-mast bracket, are made of passivated
stainless steel. The seven long bolts are plated
with a thick layer of cadmium with protective
coating of clear chromate. The internal tooth
type lockwashers used in this antenna are
made of a slightly magnetic grade of stainless
steel. The element compression clamps are
made of T304 passivated stainless steel. All
other metallic parts are aluminum. All
insulators are made of either black
polyethylene, black CycolacO or black fiber-
filled styron.
For example, if the forward power is 120
watts and the reflected power is 8 watts
Hy-Gain now recommends genuine Penetrox-
AO from Burndy Corporation for use as an
antielectrolytic compound within element
assemblies. This prevents aluminum oxide
from forming on the aluminum surface,
thereby maintaining high electrical
conductivity between element sections,
especially in coastal environments. No other
type of conductive paste should be used.
Penetrox-AO can be purchased in most
electrical supply outlets.
A light amount of clear lacquer or an acrylic
spray may be used to coat the exterior surface
of the element assemblies if heavy oxidation
is likely to occur. Heavy oxidation of
aluminum may occur if the antenna is
installed within 5 miles of salt water.
'I'hruline is a registered trademark of Bird Electronics.
Cycolac Is a registered trademark of Borg-Warner. Penetrox-
A is a registered trademark of Burndy Corporation.