BIG SIGNAL Unun 9:1
9:1 Unun for Matching High-Impedance Wire Antennas to 50-Ohm Coaxial Feed Lines
The BIG SIGNAL Unun 9:1 is a high-performance 9:1 unbalanced impedance transformer designed to provide the transition between a 50-ohm unbalanced coaxial feed line and an unbalanced antenna or load with an impedance close to 450 Ohms.
It is especially well suited for long-wire antennas and other high-impedance unbalanced antenna systems, where its 9:1 transformation ratio can reduce an impedance close to 450 Ohms toward a nominal value of approximately 50 Ohms, making it easier to connect the antenna to a coaxial feed line and the station's matching system.
Type: Unun / unbalanced impedance transformer
Ratio: 9:1
Application: high-impedance unbalanced antennas and loads
Nominal impedance: approximately 450 Ohms / 50 Ohms
Feed line: 50-ohm coaxial cable
Primary function: unbalanced-to-unbalanced impedance transformation
Typical applications: long-wire / random-wire / end-fed antennas and other compatible unbalanced antenna systems
Why Use a 9:1 Unun?
• Transforms high impedances
Its 9:1 ratio can transform an impedance close to 450 Ohms toward approximately 50 Ohms, making it easier to connect certain high-impedance wire antennas to conventional coaxial feed lines.
• Unbalanced-to-unbalanced transition
Unlike a balun, the Unun is designed to provide impedance transformation between an unbalanced transmission line and an unbalanced load, making it suitable for this type of antenna system.
• Especially suited for wire antennas
It is a suitable solution for certain long-wire, random-wire, and end-fed antenna configurations whose feed-point impedance falls within a range compatible with the transformation provided by the Unun.
• Facilitates matching to a 50-Ohm system
By reducing a high impedance toward a value closer to 50 Ohms, it can make impedance matching easier for the feed system and, when required, the antenna tuner.
• Flexible matching for multiband installations
When used with multiband wire antennas, the 9:1 Unun can provide a useful impedance transformation before final matching is performed with a compatible antenna tuner or matching unit.
Impedance Transformation for Unbalanced Antennas
The BIG SIGNAL Unun 9:1 is specifically designed for systems where both the transmission line and the load are unbalanced, providing a 9:1 impedance transformation ratio that facilitates feeding certain wire antennas with considerably higher impedances from a 50-ohm coaxial feed line.
• Long-wire antennas with compatible feed-point impedances.
• Random-wire configurations.
• Certain end-fed antennas.
• Systems with high-impedance unbalanced loads.
• Installations requiring a nominal transformation from 450 to 50 Ohms.
• Systems using an antenna tuner for final impedance matching.
A 9:1 transformation does not mean that every wire antenna will automatically present 50 Ohms.
The actual impedance of a wire antenna depends on factors such as its length, operating frequency, height, surrounding environment, ground or counterpoise system, and installation configuration. The Unun provides a 9:1 impedance transformation, but in multiband installations an antenna tuner may be required for final matching.
9:1 Transformation. From High Impedance to 50 Ohms.
The BIG SIGNAL Unun 9:1 provides an effective solution for impedance transformation in unbalanced antenna systems, facilitating the use of 50-ohm coaxial feed lines with compatible wire antennas and other high-impedance unbalanced loads.
Technical Specifications
Frequency range: 1 – 52 MHz
Input impedance: 450 Ohms
Output impedance: 50 Ohms
Transformation ratio: 9:1
Insertion loss: < 0.1 dB
Maximum power: 2,000 W PEP
Type: 9:1 Unun
Function: impedance transformation between unbalanced systems
450 / 50 Ohms • 9:1 • 1 – 52 MHz • 2,000 W PEP • < 0.1 dB
The BIG SIGNAL Unun 9:1 is designed to provide a nominal impedance transformation from 450 Ohms to 50 Ohms, with an operating range of 1 to 52 MHz, insertion loss below 0.1 dB, and a specified maximum power rating of 2,000 W PEP.
Construction and Materials
• Copper winding with PTFE insulation
The winding is made from high-quality copper protected by heavy-duty PTFE tubing, selected to provide stable RF performance and handle the specified power levels.
• Ni-Zn toroidal core
Uses a low-initial-permeability nickel-zinc (Ni-Zn) ferrite toroid as the magnetic component to provide the 9:1 impedance transformation throughout the specified operating range.
• Stainless steel hardware
Fastening hardware is made from stainless steel, providing mechanical strength, corrosion resistance, and long-term durability.
• SO-239 connector with PTFE insulation
Equipped with an SO-239 connector featuring PTFE insulation, suitable for RF applications and high power levels.
9:1 Transformation. From 450 to 50 Ohms. Minimal Insertion Loss.
The BIG SIGNAL Unun 9:1 combines a nominal impedance transformation from 450 to 50 Ohms, an operating range of 1 to 52 MHz, insertion loss below 0.1 dB, and a specified maximum power rating of 2,000 W PEP, using a PTFE-protected copper winding, Ni-Zn ferrite toroidal core, and SO-239 connector with PTFE insulation.
The purchase of the products is always made on request. We manufacture all products, so manufacturing times can be added. That is why the final price of the purchase, as the final price of the shipping costs will be confirmed in an email sent afterwards.
The form of payment will be made once the email is received, so at all times you can cancel the order informing us of the process.
ES
EN
No reviews for this article yet. Be the first to add one.