ECO ANTENNE UU91
Magnetic Un-Un for long wire Waterproof version
9:1 un-un ratio 150 watts
Get on air with just a few meters of wire..!
It can be used with reduced efficiency up to 150 MHz
The UU91T is a 1:9 ratio transformer. It reduces the high impedance of a short wire into a range that can then be tuned by a common tuner. The balun must be placed directly at the wire antenna connection point.
The UU91 is then connected to the tuner via coaxial cable, the SWR will be less than 3:1, and losses will be low.
The antenna length must be at least 6m. The ground connection must be good. If a ground connection is not available at the balun, at least the TRX must be grounded. If necessary, insert a common mode filter before the balun. A counterpoise can be used instead of the ground connection.
The UU91 can be used not only with a wire, but with any metallic object, water pipes, gutters, CB antennas (in this case, before use, remove the matching elements from the antenna). The UU91 is also an excellent tool for experimenters...
Obviously, it can be used for transmission, max. power of 150 W PEP.
For SWLs, the UU91 is an ideal accessory: a simple wire connected to a receiver has very poor and inefficient coupling; with the MTFT, the coupling will be greatly improved. It is not necessary to add an additional tuning unit.
