::: FREQUENTLY ASKED QUESTIONS

What is s the difference between SPECTRAL Isopole antennas for VHF and UHF and the other omnidirectional antennas for base stations?

The highly 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.

In other type of antennas, the transmission line produces a parasitic effect which deforms the radiation pattern and reduces the performance.

What application can the Spectral Isopole antennas have?

Owing 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.

As regards the so called “Fiberglass Antennas”. Why is the SPECTRAL a better option?

Most of 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.

The static 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 high.

As it 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.

The fiberglass 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 .

And How about durability?

It’s important 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.

On the 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.

What is the Gain of the SPECTRAL?

Most manufacturers 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.

The Spectral 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.

Is the assembly and tuning complicated?

Definitively not. The Spectral Isopole antennas are supplied, tested and pre-tuned.
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.

Are the Spectral antennas expensive?

In spite 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 tuned


 

 




I Home I Products I Test I Prices I Faq I Technical Support I Contact I

© Copyright 2010, Spectral Antennas, All Rights Reserved