Balun Buatan Sendiri 1:1

Sumber: http://195.84.101.101/~goranl/building/aircore_balun/index.html

- 1:1 HomeBrew AirCore Balun - 2007.05.20 Made this 'AirCore' balun for use with a singe band portable 80M dipole. The manufacturing is quite simple and the result is a nice and very 'Heavy Duty' baluna.

This type of balun is normally used with broad-band or multi-band wire antennas,- where gamma-match or other narrow-band matching is not suitable. The baluna is also suitable for use with logo-periodic or multi-band directional Yagi antennas.

- Technical data -

SPECIFICATIONS

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Frequency responce ... 3-30 MHz Maximun Input Power .. At least 1 KW Input Impedance ...... 50ohm unbalanced Impedance ratio ...... 1:1 (In/Out) Dimensions ........... Weight ...............

- Making the balun -

Principle - The coils on an air balun is not different from an Ferrite-balun, in the layout above you see the principle. Two coils (Yellow & red) is used as straight thru-feed, one for center conductor an the other for the shield conductor, they are connected directly to each dipole half, The blue coil is used for reversed 'pick-up' and balances the dipole connections.

The Air-balun is made on a plastic 'Nonconducting' core,- Use a pice of plastic tubing about 25mm in diameter and about 66mm long. Drill tree 2mm holes,- slightly in diagonal in one end, whith about 5mm distance. drill tree 2mm holes in the same manner in the other end of the tube,- distance between the two hole-rows is 49mm.

(On the images below i use 2mm Cu wire, the measurements given in this text is calculated using 1,5mm cu-wire)