Antennas 3/3

50 to 100 ohm transformer for receiving systems.

5 turns input 7 turns output Used material: 1 core of 73 material Fair-Rite 2873000202 Input = 5 turns / Output = 7 turns 5...

xtgaby

Sep 28, 20201 min read

50 to 75 ohm transformer for receiving systems.

4 turns input 5 turns output Used material: 1 core of 73 material Fair-Rite 2873000202 Input = 4 turns / Output = 5 turns 4 square...

xtgaby

Sep 24, 20201 min read

9:1 transformer for K9AY antenna.

Picture Schematics primary 2 turns secondary 6 turns Used material: 3 cores of 73 material Fair-Rite 2873000202 Input = 2 turns ...

xtgaby

Sep 17, 20201 min read

Case study, how many turns are needed?

Picture Schematics Number of turns left = number of turns right. L value: XL value @ 1 MHz 1 turn: 0,02 mH 125 Ohms...

xtgaby

Sep 3, 20201 min read

Transformers for receiving antennas.

Used material: 73 material Fair-Rite 2873000202 How to build and measure. 1) One core 2 turns left and 3 turns right. Input = 2 turns / ...

xtgaby

Jul 29, 20201 min read

Building and measuring ununs

Remark: all return loss measurements (SWR) are with a light inductive load (adjustable resistor). Real results are always better then...

xtgaby

Jun 1, 20202 min read

Magnetic loop 160 meter.

Calculated coil value of the loop is 6.4 uH as explained in de 40 meter band loop. Target frequency = 1.858 KHz Calculated capacity...

xtgaby

May 31, 20201 min read

Magnetic loop 80 meter band.

Calculated coil value of the loop is 6.4 uH as explained in de 40 meter band loop. Target frequency = 3.700 KHz Calculated value for the...

xtgaby

May 30, 20201 min read

Magnetic loop 40 meter band.

Alu tube 22 mm diameter lengt = 6 meter ==> diameter loop = 2 meter. Small loop to insert the signal =1.30 meter for best SWR figures. At...

xtgaby

May 27, 20201 min read

Building and measuring baluns (Part II). Another approach 1 core instead of 2.

See remarks on post "Guanella balun 1 core versus 2 separated cores". Return loss measurement: Left: FT 240-43 ...

xtgaby

Mar 28, 20201 min read

Conversion tables

For people who are not used to work in dB. Loss compared to input signal. VSWR compared to Return Loss (dB

xtgaby

Mar 15, 20201 min read

How to measure the impedance of a transmission line?

If you have a transmission line (coax or open line) with an unknown impedance, I will explain here how to measure this. Above: far end of...

xtgaby

Feb 23, 20201 min read

Building and measuring baluns (Part I).

The 1: 4 Guanella current Balun with FT240 - 31 core. Material used: FT240-31 (outer diameter is 2.4 inch material = 31) Just Google...

xtgaby

Feb 9, 20202 min read

The use of stubs.

Every impedance can be matched with the use of two components. Capacitor or inductor. Dependent of the place you are on the smith...

xtgaby

Jan 11, 20191 min read

A practical example.

I have made a vertical antenna with a lengt of 10 meters and two radials of 10 meters also connected to the ground. This antenna...

xtgaby

Jan 11, 20191 min read

Antenne analysis and matching.

How to measure antenna impedance? Different types of VNA can be used. When using a professional VNA (Agilent, R/S,…) the measuring cable...

xtgaby

Jan 9, 20191 min read