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This project assembles a 49:1 ferrite-core (“FT”) type #43 transformer that matches 50 ohm input to 2500 ohm end fed antenna. It is optimized for 3.5/7/10/14 MHz but will work reasonably well on all amateur bands from 80 meters thru 10 meters with a 135 foot length of wire and a short connection to ground.
22 lut 2021 · The following is a list of materials required to make a 49:1 unun impedance transformer for an end-fed half wave antenna. You will also need a half-wavelength length of wire (14 or 12 gauge typically) in order to construct an antenna radiator for whichever ham band you choose.
The 49:1 impedance transformer ( or 64:1 ) will help you bring down the high impedance of your resonant EFHW antenna to almost 50 Ohm. Let’s have a look at a few details on how to build a 49:1, or a 64:1 impedance transformer.
31 gru 2022 · Dzięki zamontowaniu śrub z oczkami na przeciwległych ściankach budowany transformator dopasowujący będzie mógł być włączany szeregowo pomiędzy promiennik oraz przeciwległą linkę napinającą UN-UN do ziemi lub innego elementu, na przykład pnia drzewa.
The heart and engineering of its design is in its 49:1 impedance matching transformer, or unun (connects an unbalanced feed line to an unbalanced radiating element,) where much of this DIY is focused. The 132-foot half-wave radiating element presents about an 1800 ohm (at 10 meters) to 5000 ohm (at 80 meters) impedance to an end-fed feed point.
20 lip 2021 · 1) More primary turns and primary inductance improve the transformer efficiency and low end performance. 2) Winding capacitance and leakage inductance, especially present as you increase the number of turns, limit the high frequency performance.
An impedance transformer (49:1) to feed a high impedance, end fed (unbalanced) random wire which is likely to be a few hundred ohms, and transform it into something closer to a 50Ω (unbalanced) coaxial input.
