FREQUENTLY ASKED QUESTIONS
is s the difference between SPECTRAL Isopole antennas for
VHF and UHF and the other omnidirectional antennas for base
advanced technology in the design of the decoupling of the
transmission line as regards the antenna , produces a predictable
radiation pattern enhancing the performance, so the energy
is radiated at a low angle and completely ommidirectional.
type of antennas, the transmission line produces a parasitic
effect which deforms the radiation pattern and reduces the
application can the Spectral Isopole antennas have?
to their technical characteristics, precision in construction,
broadband and power handling, they have been used for a long
time for extreme applications, giving an outstanding service
in base stations from the Antarctica to repeaters in dessert
areas, as well as in Military applications, warships, trunking
systems, telemetry and extensive Amateur use. There are different
models for different applications.
regards the so called “Fiberglass Antennas”. Why is the SPECTRAL
a better option?
the antennas encapsulated in fiberglass for amateur use are
economically constructed , i.e., they are covered and supported
by thin-walled tubing which makes the antenna sway like a
“whip” in windy weather conditions, changing unpredictably
the radiation pattern, weakening or losing the signal in both
reception and transmission.
noise as a result of the friction of the wind with the fiberglass,
makes the reception and transmission difficult or impossible
in data communications, because the B.E.R. (Bit Error Rate)
is well-known, the fiberglass antennas are too prone to receiving
lightening discharges. The friction of the wind with the fiberglass
increases the production of ozone in the air which is the
chosen way for the lightening to discharge.
antennas for professional use have a rigid structure of fiberglass,
D.C. grounded and their price is much higher (at least 4 o
5 times) than these so called amateur fiberglass antennas
How about durability?
to highlight that the Spectral Isopole antennas are manufactured
in such a way so as to withstand the harshest weather conditions.
They are manufactured with anti corrosion Navy-Type aluminum,
stainless steel, and insulation UV resistant materials mainly
manufactured for satellite applications. Moreover, the connector
is outdoor protected.
other hand, fiberglass antennas both for amateur and professional
use, have a limited duration. Since the UV rays deteriorate
the fiberglass making the humidity leak inside the antenna
and therefore, not only breaking, but also affecting its proper
functioning or even leaving it out of service.
is the Gain of the SPECTRAL?
claim Fantasy Gains of their products by increasing the gain
of their antennas “Magically” every time they produce a new
catalog from one year to the next with the aim of increasing
their sales. To prove this, many Famous Makes claim different
gains for the same design or product in different frequencies:
This means that for Amateur use they increase the gain, just
for a question of marketing. Instead, in antennas for professional
applications, where engineering calculations are used and
a simple mistake of a FRACTION of Db would make the difference
between getting through or not , these manufacturers claim
gains up to 3 times less for the same product or design offered
for Ham Radio.
Isopole has a gain of HONEST 3,85 Dbd , that means taking
as reference a ½ wave dipole antenna, with a zero degree
radiation angle, so the maximum gain oriented to the horizon,
outperforming most well-known antennas claiming about 8Db.
the assembly and tuning complicated?
not. The Spectral Isopole antennas are supplied, tested and
They only need a metal tube as mast, for assembling and installation.
Its does not take longer than 15 minutes for tuning according
to the tuning chart provided with the antenna.
The model for UHF is supplied tuned for both amateur or commercial
frequencies and for a little additional cost can be ordered
for the frequency required.
the Spectral antennas expensive?
of their robust design and handcraft precision, made one by
one with materials of the highest standards, the Spectral
Isopole antennas have a lower price than many commercial antennas
advertised as “TOP” giving an excellent service and durability
even more than many antennas for professional use which are
much more expensive than the Spectral. also, They cannot be
compared with antennas supplied as a collection of tubing
and clamps inside a box, to be assembled by the customer like
a puzzle, wasting time, and probably, and if in luck perhaps